--- /dev/null
+This is the Readme file for the libs-device directory. This directory contains
+code snippets which may be useful for USB device firmware.
+
+
+WHAT IS INCLUDED IN THIS DIRECTORY?
+===================================
+
+osccal.c and osccal.h
+ This module contains a function which calibrates the AVR's built-in RC
+ oscillator based on the USB frame clock. See osccal.h for a documentation
+ of the API.
+
+osctune.h
+ This header file contains a code snippet for usbconfig.h. With this code,
+ you can keep the AVR's internal RC oscillator in sync with the USB frame
+ clock. This is a continuous synchronization, not a single calibration at
+ USB reset as with osccal.c above. Please note that this code works only
+ if D- is wired to the interrupt, not D+.
+
+----------------------------------------------------------------------------
+(c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH.
+http://www.obdev.at/
--- /dev/null
+/* Name: osccal.c
+ * Author: Christian Starkjohann
+ * Creation Date: 2008-04-10
+ * Tabsize: 4
+ * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+#include <avr/io.h>
+
+#ifndef uchar
+#define uchar unsigned char
+#endif
+
+/* ------------------------------------------------------------------------- */
+/* ------------------------ Oscillator Calibration ------------------------- */
+/* ------------------------------------------------------------------------- */
+
+/* Calibrate the RC oscillator. Our timing reference is the Start Of Frame
+ * signal (a single SE0 bit) repeating every millisecond immediately after
+ * a USB RESET. We first do a binary search for the OSCCAL value and then
+ * optimize this value with a neighboorhod search.
+ */
+void calibrateOscillator(void)
+{
+uchar step = 128;
+uchar trialValue = 0, optimumValue;
+int x, optimumDev, targetValue = (unsigned)(1499 * (double)F_CPU / 10.5e6 + 0.5);
+
+ /* do a binary search: */
+ do{
+ OSCCAL = trialValue + step;
+ x = usbMeasureFrameLength(); /* proportional to current real frequency */
+ if(x < targetValue) /* frequency still too low */
+ trialValue += step;
+ step >>= 1;
+ }while(step > 0);
+ /* We have a precision of +/- 1 for optimum OSCCAL here */
+ /* now do a neighborhood search for optimum value */
+ optimumValue = trialValue;
+ optimumDev = x; /* this is certainly far away from optimum */
+ for(OSCCAL = trialValue - 1; OSCCAL <= trialValue + 1; OSCCAL++){
+ x = usbMeasureFrameLength() - targetValue;
+ if(x < 0)
+ x = -x;
+ if(x < optimumDev){
+ optimumDev = x;
+ optimumValue = OSCCAL;
+ }
+ }
+ OSCCAL = optimumValue;
+}
+/*
+Note: This calibration algorithm may try OSCCAL values of up to 192 even if
+the optimum value is far below 192. It may therefore exceed the allowed clock
+frequency of the CPU in low voltage designs!
+You may replace this search algorithm with any other algorithm you like if
+you have additional constraints such as a maximum CPU clock.
+For version 5.x RC oscillators (those with a split range of 2x128 steps, e.g.
+ATTiny25, ATTiny45, ATTiny85), it may be useful to search for the optimum in
+both regions.
+*/
--- /dev/null
+/* Name: osccal.h
+ * Author: Christian Starkjohann
+ * Creation Date: 2008-04-10
+ * Tabsize: 4
+ * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/*
+General Description:
+This module contains a function which calibrates the AVR's internal RC
+oscillator so that the CPU runs at F_CPU (F_CPU is a macro which must be
+defined when the module is compiled, best passed in the compiler command
+line). The time reference is the USB frame clock of 1 kHz available
+immediately after a USB RESET condition. Timing is done by counting CPU
+cycles, so all interrupts must be disabled while the calibration runs. For
+low level timing measurements, usbMeasureFrameLength() is called. This
+function must be enabled in usbconfig.h by defining
+USB_CFG_HAVE_MEASURE_FRAME_LENGTH to 1. It is recommended to call
+calibrateOscillator() from the reset hook in usbconfig.h:
+
+#ifndef __ASSEMBLER__
+#include <avr/interrupt.h> // for sei()
+extern void calibrateOscillator(void);
+#endif
+#define USB_RESET_HOOK(resetStarts) if(!resetStarts){cli(); calibrateOscillator(); sei();}
+
+This routine is an alternative to the continuous synchronization described
+in osctune.h.
+
+Algorithm used:
+calibrateOscillator() first does a binary search in the OSCCAL register for
+the best matching oscillator frequency. Then it does a next neighbor search
+to find the value with the lowest clock rate deviation. It is guaranteed to
+find the best match among neighboring values, but for version 5 oscillators
+(which have a discontinuous relationship between OSCCAL and frequency) a
+better match might be available in another OSCCAL region.
+
+Limitations:
+This calibration algorithm may try OSCCAL values of up to 192 even if the
+optimum value is far below 192. It may therefore exceed the allowed clock
+frequency of the CPU in low voltage designs!
+Precision depends on the OSCCAL vs. frequency dependency of the oscillator.
+Typical precision for an ATMega168 (derived from the OSCCAL vs. F_RC diagram
+in the data sheet) should be in the range of 0.4%. Only the 12.8 MHz and
+16.5 MHz versions of V-USB (with built-in receiver PLL) can tolerate this
+deviation! All other frequency modules require at least 0.2% precision.
+*/
+
+#ifndef __OSCCAL_H_INCLUDED__
+#define __OSCCAL_H_INCLUDED__
+
+void calibrateOscillator(void);
+/* This function calibrates the RC oscillator so that the CPU runs at F_CPU.
+ * It MUST be called immediately after the end of a USB RESET condition!
+ * Disable all interrupts during the call!
+ * It is recommended that you store the resulting value in EEPROM so that a
+ * good guess value is available after the next reset.
+ */
+
+
+#endif /* __OSCCAL_H_INCLUDED__ */
--- /dev/null
+/* Name: osctune.h
+ * Author: Christian Starkjohann
+ * Creation Date: 2008-10-18
+ * Tabsize: 4
+ * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/*
+General Description:
+This file is declared as C-header file although it is mostly documentation
+how the RC oscillator can be kept in sync to the USB frame rate. The code
+shown here must be added to usbconfig.h or this header file is included from
+there. This code works only if D- is wired to the interrupt, not D+!!!
+
+This is an alternative to the osccal routine in osccal.c. It has the advantage
+that the synchronization is done continuously and that it has more compact
+code size. The disadvantages are slow synchronization (it may take a while
+until the driver works), that messages immediately after the SOF pulse may be
+lost (and need to be retried by the host) and that the interrupt is on D-
+contrary to most examples.
+
+You may want to store a good calibration value in EEPROM for the next startup.
+You know that the calibration value is good when the first USB message is
+received. Do not store the value on every received message because the EEPROM
+has a limited endurance.
+
+Notes:
+(*) You must declare the global character variable "lastTimer0Value" in your
+main code.
+
+(*) Timer 0 must be free running (not written by your code) and the prescaling
+must be consistent with the TIMER0_PRESCALING define.
+
+(*) Good values for Timer 0 prescaling depend on how precise the clock must
+be tuned and how far away from the default clock rate the target clock is.
+For precise tuning, choose a low prescaler factor, for a broad range of tuning
+choose a high one. A prescaler factor of 64 is good for the entire OSCCAL
+range and allows a precision of better than +/-1%. A prescaler factor of 8
+allows tuning to slightly more than +/-6% of the default frequency and is
+more precise than one step of OSCCAL. It is therefore not suitable to tune an
+8 MHz oscillator to 12.5 MHz.
+
+Thanks to Henrik Haftmann for the idea to this routine!
+*/
+
+#define TIMER0_PRESCALING 64 /* must match the configuration for TIMER0 in main */
+#define TOLERATED_DEVIATION_PPT 5 /* max clock deviation before we tune in 1/10 % */
+/* derived constants: */
+#define EXPECTED_TIMER0_INCREMENT ((F_CPU / (1000 * TIMER0_PRESCALING)) & 0xff)
+#define TOLERATED_DEVIATION (TOLERATED_DEVIATION_PPT * F_CPU / (1000000 * TIMER0_PRESCALING))
+
+#ifdef __ASSEMBLER__
+macro tuneOsccal
+ push YH ;[0]
+ in YL, TCNT0 ;[2]
+ lds YH, lastTimer0Value ;[3]
+ sts lastTimer0Value, YL ;[5]
+ sub YL, YH ;[7] time passed since last frame
+ subi YL, EXPECTED_TIMER0_INCREMENT ;[8]
+#if OSCCAL > 0x3f /* outside I/O addressable range */
+ lds YH, OSCCAL ;[6]
+#else
+ in YH, OSCCAL ;[6] assembler modle uses __SFR_OFFSET == 0
+#endif
+ cpi YL, TOLERATED_DEVIATION + 1 ;[10]
+ brmi notTooHigh ;[11]
+ subi YH, 1 ;[12] clock rate was too high
+; brcs tuningOverflow ; optionally check for overflow
+ rjmp osctuneDone ;[13]
+notTooHigh:
+ cpi YL, -TOLERATED_DEVIATION ;[13]
+ brpl osctuneDone ;[14] not too low
+ inc YH ;[15] clock rate was too low
+; breq tuningOverflow ; optionally check for overflow
+osctuneDone:
+#if OSCCAL > 0x3f /* outside I/O addressable range */
+ sts OSCCAL, YH ;[12-13] store tuned value
+#else
+ out OSCCAL, YH ;[12-13] store tuned value
+#endif
+tuningOverflow:
+ pop YH ;[17]
+ endm ;[19] max number of cycles
+#endif
+
+#define USB_SOF_HOOK tuneOsccal
--- /dev/null
+This file documents changes in the firmware-only USB driver for atmel's AVR
+microcontrollers. New entries are always appended to the end of the file.
+Scroll down to the bottom to see the most recent changes.
+
+2005-04-01:
+ - Implemented endpoint 1 as interrupt-in endpoint.
+ - Moved all configuration options to usbconfig.h which is not part of the
+ driver.
+ - Changed interface for usbVendorSetup().
+ - Fixed compatibility with ATMega8 device.
+ - Various minor optimizations.
+
+2005-04-11:
+ - Changed interface to application: Use usbFunctionSetup(), usbFunctionRead()
+ and usbFunctionWrite() now. Added configuration options to choose which
+ of these functions to compile in.
+ - Assembler module delivers receive data non-inverted now.
+ - Made register and bit names compatible with more AVR devices.
+
+2005-05-03:
+ - Allow address of usbRxBuf on any memory page as long as the buffer does
+ not cross 256 byte page boundaries.
+ - Better device compatibility: works with Mega88 now.
+ - Code optimization in debugging module.
+ - Documentation updates.
+
+2006-01-02:
+ - Added (free) default Vendor- and Product-IDs bought from voti.nl.
+ - Added USBID-License.txt file which defines the rules for using the free
+ shared VID/PID pair.
+ - Added Readme.txt to the usbdrv directory which clarifies administrative
+ issues.
+
+2006-01-25:
+ - Added "configured state" to become more standards compliant.
+ - Added "HALT" state for interrupt endpoint.
+ - Driver passes the "USB Command Verifier" test from usb.org now.
+ - Made "serial number" a configuration option.
+ - Minor optimizations, we now recommend compiler option "-Os" for best
+ results.
+ - Added a version number to usbdrv.h
+
+2006-02-03:
+ - New configuration variable USB_BUFFER_SECTION for the memory section where
+ the USB rx buffer will go. This defaults to ".bss" if not defined. Since
+ this buffer MUST NOT cross 256 byte pages (not even touch a page at the
+ end), the user may want to pass a linker option similar to
+ "-Wl,--section-start=.mybuffer=0x800060".
+ - Provide structure for usbRequest_t.
+ - New defines for USB constants.
+ - Prepared for HID implementations.
+ - Increased data size limit for interrupt transfers to 8 bytes.
+ - New macro usbInterruptIsReady() to query interrupt buffer state.
+
+2006-02-18:
+ - Ensure that the data token which is sent as an ack to an OUT transfer is
+ always zero sized. This fixes a bug where the host reports an error after
+ sending an out transfer to the device, although all data arrived at the
+ device.
+ - Updated docs in usbdrv.h to reflect changed API in usbFunctionWrite().
+
+* Release 2006-02-20
+
+ - Give a compiler warning when compiling with debugging turned on.
+ - Added Oleg Semyonov's changes for IAR-cc compatibility.
+ - Added new (optional) functions usbDeviceConnect() and usbDeviceDisconnect()
+ (also thanks to Oleg!).
+ - Rearranged tests in usbPoll() to save a couple of instructions in the most
+ likely case that no actions are pending.
+ - We need a delay between the SET ADDRESS request until the new address
+ becomes active. This delay was handled in usbPoll() until now. Since the
+ spec says that the delay must not exceed 2ms, previous versions required
+ aggressive polling during the enumeration phase. We have now moved the
+ handling of the delay into the interrupt routine.
+ - We must not reply with NAK to a SETUP transaction. We can only achieve this
+ by making sure that the rx buffer is empty when SETUP tokens are expected.
+ We therefore don't pass zero sized data packets from the status phase of
+ a transfer to usbPoll(). This change MAY cause troubles if you rely on
+ receiving a less than 8 bytes long packet in usbFunctionWrite() to
+ identify the end of a transfer. usbFunctionWrite() will NEVER be called
+ with a zero length.
+
+* Release 2006-03-14
+
+ - Improved IAR C support: tiny memory model, more devices
+ - Added template usbconfig.h file under the name usbconfig-prototype.h
+
+* Release 2006-03-26
+
+ - Added provision for one more interrupt-in endpoint (endpoint 3).
+ - Added provision for one interrupt-out endpoint (endpoint 1).
+ - Added flowcontrol macros for USB.
+ - Added provision for custom configuration descriptor.
+ - Allow ANY two port bits for D+ and D-.
+ - Merged (optional) receive endpoint number into global usbRxToken variable.
+ - Use USB_CFG_IOPORTNAME instead of USB_CFG_IOPORT. We now construct the
+ variable name from the single port letter instead of computing the address
+ of related ports from the output-port address.
+
+* Release 2006-06-26
+
+ - Updated documentation in usbdrv.h and usbconfig-prototype.h to reflect the
+ new features.
+ - Removed "#warning" directives because IAR does not understand them. Use
+ unused static variables instead to generate a warning.
+ - Do not include <avr/io.h> when compiling with IAR.
+ - Introduced USB_CFG_DESCR_PROPS_* in usbconfig.h to configure how each
+ USB descriptor should be handled. It is now possible to provide descriptor
+ data in Flash, RAM or dynamically at runtime.
+ - STALL is now a status in usbTxLen* instead of a message. We can now conform
+ to the spec and leave the stall status pending until it is cleared.
+ - Made usbTxPacketCnt1 and usbTxPacketCnt3 public. This allows the
+ application code to reset data toggling on interrupt pipes.
+
+* Release 2006-07-18
+
+ - Added an #if !defined __ASSEMBLER__ to the warning in usbdrv.h. This fixes
+ an assembler error.
+ - usbDeviceDisconnect() takes pull-up resistor to high impedance now.
+
+* Release 2007-02-01
+
+ - Merged in some code size improvements from usbtiny (thanks to Dick
+ Streefland for these optimizations!)
+ - Special alignment requirement for usbRxBuf not required any more. Thanks
+ again to Dick Streefland for this hint!
+ - Reverted to "#warning" instead of unused static variables -- new versions
+ of IAR CC should handle this directive.
+ - Changed Open Source license to GNU GPL v2 in order to make linking against
+ other free libraries easier. We no longer require publication of the
+ circuit diagrams, but we STRONGLY encourage it. If you improve the driver
+ itself, PLEASE grant us a royalty free license to your changes for our
+ commercial license.
+
+* Release 2007-03-29
+
+ - New configuration option "USB_PUBLIC" in usbconfig.h.
+ - Set USB version number to 1.10 instead of 1.01.
+ - Code used USB_CFG_DESCR_PROPS_STRING_DEVICE and
+ USB_CFG_DESCR_PROPS_STRING_PRODUCT inconsistently. Changed all occurrences
+ to USB_CFG_DESCR_PROPS_STRING_PRODUCT.
+ - New assembler module for 16.5 MHz RC oscillator clock with PLL in receiver
+ code.
+ - New assembler module for 16 MHz crystal.
+ - usbdrvasm.S contains common code only, clock-specific parts have been moved
+ to usbdrvasm12.S, usbdrvasm16.S and usbdrvasm165.S respectively.
+
+* Release 2007-06-25
+
+ - 16 MHz module: Do SE0 check in stuffed bits as well.
+
+* Release 2007-07-07
+
+ - Define hi8(x) for IAR compiler to limit result to 8 bits. This is necessary
+ for negative values.
+ - Added 15 MHz module contributed by V. Bosch.
+ - Interrupt vector name can now be configured. This is useful if somebody
+ wants to use a different hardware interrupt than INT0.
+
+* Release 2007-08-07
+
+ - Moved handleIn3 routine in usbdrvasm16.S so that relative jump range is
+ not exceeded.
+ - More config options: USB_RX_USER_HOOK(), USB_INITIAL_DATATOKEN,
+ USB_COUNT_SOF
+ - USB_INTR_PENDING can now be a memory address, not just I/O
+
+* Release 2007-09-19
+
+ - Split out common parts of assembler modules into separate include file
+ - Made endpoint numbers configurable so that given interface definitions
+ can be matched. See USB_CFG_EP3_NUMBER in usbconfig-prototype.h.
+ - Store endpoint number for interrupt/bulk-out so that usbFunctionWriteOut()
+ can handle any number of endpoints.
+ - Define usbDeviceConnect() and usbDeviceDisconnect() even if no
+ USB_CFG_PULLUP_IOPORTNAME is defined. Directly set D+ and D- to 0 in this
+ case.
+
+* Release 2007-12-01
+
+ - Optimize usbDeviceConnect() and usbDeviceDisconnect() for less code size
+ when USB_CFG_PULLUP_IOPORTNAME is not defined.
+
+* Release 2007-12-13
+
+ - Renamed all include-only assembler modules from *.S to *.inc so that
+ people don't add them to their project sources.
+ - Distribute leap bits in tx loop more evenly for 16 MHz module.
+ - Use "macro" and "endm" instead of ".macro" and ".endm" for IAR
+ - Avoid compiler warnings for constant expr range by casting some values in
+ USB descriptors.
+
+* Release 2008-01-21
+
+ - Fixed bug in 15 and 16 MHz module where the new address set with
+ SET_ADDRESS was already accepted at the next NAK or ACK we send, not at
+ the next data packet we send. This caused problems when the host polled
+ too fast. Thanks to Alexander Neumann for his help and patience debugging
+ this issue!
+
+* Release 2008-02-05
+
+ - Fixed bug in 16.5 MHz module where a register was used in the interrupt
+ handler before it was pushed. This bug was introduced with version
+ 2007-09-19 when common parts were moved to a separate file.
+ - Optimized CRC routine (thanks to Reimar Doeffinger).
+
+* Release 2008-02-16
+
+ - Removed outdated IAR compatibility stuff (code sections).
+ - Added hook macros for USB_RESET_HOOK() and USB_SET_ADDRESS_HOOK().
+ - Added optional routine usbMeasureFrameLength() for calibration of the
+ internal RC oscillator.
+
+* Release 2008-02-28
+
+ - USB_INITIAL_DATATOKEN defaults to USBPID_DATA1 now, which means that we
+ start with sending USBPID_DATA0.
+ - Changed defaults in usbconfig-prototype.h
+ - Added free USB VID/PID pair for MIDI class devices
+ - Restructured AVR-USB as separate package, not part of PowerSwitch any more.
+
+* Release 2008-04-18
+
+ - Restructured usbdrv.c so that it is easier to read and understand.
+ - Better code optimization with gcc 4.
+ - If a second interrupt in endpoint is enabled, also add it to config
+ descriptor.
+ - Added config option for long transfers (above 254 bytes), see
+ USB_CFG_LONG_TRANSFERS in usbconfig.h.
+ - Added 20 MHz module contributed by Jeroen Benschop.
+
+* Release 2008-05-13
+
+ - Fixed bug in libs-host/hiddata.c function usbhidGetReport(): length
+ was not incremented, pointer to length was incremented instead.
+ - Added code to command line tool(s) which claims an interface. This code
+ is disabled by default, but may be necessary on newer Linux kernels.
+ - Added usbconfig.h option "USB_CFG_CHECK_DATA_TOGGLING".
+ - New header "usbportability.h" prepares ports to other development
+ environments.
+ - Long transfers (above 254 bytes) did not work when usbFunctionRead() was
+ used to supply the data. Fixed this bug. [Thanks to Alexander Neumann!]
+ - In hiddata.c (example code for sending/receiving data over HID), use
+ USB_RECIP_DEVICE instead of USB_RECIP_INTERFACE for control transfers so
+ that we need not claim the interface.
+ - in usbPoll() loop 20 times polling for RESET state instead of 10 times.
+ This accounts for the higher clock rates we now support.
+ - Added a module for 12.8 MHz RC oscillator with PLL in receiver loop.
+ - Added hook to SOF code so that oscillator can be tuned to USB frame clock.
+ - Added timeout to waitForJ loop. Helps preventing unexpected hangs.
+ - Added example code for oscillator tuning to libs-device (thanks to
+ Henrik Haftmann for the idea to this routine).
+ - Implemented option USB_CFG_SUPPRESS_INTR_CODE.
+
+* Release 2008-10-22
+
+ - Fixed libs-device/osctune.h: OSCCAL is memory address on ATMega88 and
+ similar, not offset of 0x20 needs to be added.
+ - Allow distribution under GPLv3 for those who have to link against other
+ code distributed under GPLv3.
+
+* Release 2008-11-26
+
+ - Removed libusb-win32 dependency for hid-data example in Makefile.windows.
+ It was never required and confused many people.
+ - Added extern uchar usbRxToken to usbdrv.h.
+ - Integrated a module with CRC checks at 18 MHz by Lukas Schrittwieser.
+
+* Release 2009-03-23
+
+ - Hid-mouse example used settings from hid-data example, fixed that.
+ - Renamed project to V-USB due to a trademark issue with Atmel(r).
+ - Changed CommercialLicense.txt and USBID-License.txt to make the
+ background of USB ID registration clearer.
+
+* Release 2009-04-15
+
+ - Changed CommercialLicense.txt to reflect the new range of PIDs from
+ Jason Kotzin.
+ - Removed USBID-License.txt in favor of USB-IDs-for-free.txt and
+ USB-ID-FAQ.txt
+ - Fixed a bug in the 12.8 MHz module: End Of Packet decection was made in
+ the center between bit 0 and 1 of each byte. This is where the data lines
+ are expected to change and the sampled data may therefore be nonsense.
+ We therefore check EOP ONLY if bits 0 AND 1 have both been read as 0 on D-.
+ - Fixed a bitstuffing problem in the 16 MHz module: If bit 6 was stuffed,
+ the unstuffing code in the receiver routine was 1 cycle too long. If
+ multiple bytes had the unstuffing in bit 6, the error summed up until the
+ receiver was out of sync.
+ - Included option for faster CRC routine.
+ Thanks to Slawomir Fras (BoskiDialer) for this code!
+ - Updated bits in Configuration Descriptor's bmAttributes according to
+ USB 1.1 (in particular bit 7, it is a must-be-set bit now).
+
+* Release 2009-08-22
+
+ - Moved first DBG1() after odDebugInit() in all examples.
+ - Use vector INT0_vect instead of SIG_INTERRUPT0 if defined. This makes
+ V-USB compatible with the new "p" suffix devices (e.g. ATMega328p).
+ - USB_CFG_CLOCK_KHZ setting is now required in usbconfig.h (no default any
+ more).
+ - New option USB_CFG_DRIVER_FLASH_PAGE allows boot loaders on devices with
+ more than 64 kB flash.
+ - Built-in configuration descriptor allows custom definition for second
+ endpoint now.
+
+* Release 2010-07-15
+
+ - Fixed bug in usbDriverSetup() which prevented descriptor sizes above 255
+ bytes.
+ - Avoid a compiler warning for unused parameter in usbHandleResetHook() when
+ compiler option -Wextra is enabled.
+ - Fixed wrong hex value for some IDs in USB-IDs-for-free.txt.
+ - Keep a define for USBATTR_BUSPOWER, although the flag does not exist
+ in USB 1.1 any more. Set it to 0. This is for backward compatibility.
+
+* Release 2012-01-09
+
+ - Define a separate (defined) type for usbMsgPtr so that projects using a
+ tiny memory model can define it to an 8 bit type in usbconfig.h. This
+ change also saves a couple of bytes when using a scalar 16 bit type.
+ - Inserted "const" keyword for all PROGMEM declarations because new GCC
+ requires it.
+ - Fixed problem with dependence of usbportability.h on usbconfig.h. This
+ problem occurred with IAR CC only.
+ - Prepared repository for github.com.
+
+* Release 2012-12-06
\ No newline at end of file
--- /dev/null
+V-USB Driver Software License Agreement
+Version 2012-07-09
+
+THIS LICENSE AGREEMENT GRANTS YOU CERTAIN RIGHTS IN A SOFTWARE. YOU CAN
+ENTER INTO THIS AGREEMENT AND ACQUIRE THE RIGHTS OUTLINED BELOW BY PAYING
+THE AMOUNT ACCORDING TO SECTION 4 ("PAYMENT") TO OBJECTIVE DEVELOPMENT.
+
+
+1 DEFINITIONS
+
+1.1 "OBJECTIVE DEVELOPMENT" shall mean OBJECTIVE DEVELOPMENT Software GmbH,
+Grosse Schiffgasse 1A/7, 1020 Wien, AUSTRIA.
+
+1.2 "You" shall mean the Licensee.
+
+1.3 "V-USB" shall mean all files included in the package distributed under
+the name "vusb" by OBJECTIVE DEVELOPMENT (http://www.obdev.at/vusb/)
+unless otherwise noted. This includes the firmware-only USB device
+implementation for Atmel AVR microcontrollers, some simple device examples
+and host side software examples and libraries.
+
+
+2 LICENSE GRANTS
+
+2.1 Source Code. OBJECTIVE DEVELOPMENT shall furnish you with the source
+code of V-USB.
+
+2.2 Distribution and Use. OBJECTIVE DEVELOPMENT grants you the
+non-exclusive right to use, copy and distribute V-USB with your hardware
+product(s), restricted by the limitations in section 3 below.
+
+2.3 Modifications. OBJECTIVE DEVELOPMENT grants you the right to modify
+the source code and your copy of V-USB according to your needs.
+
+2.4 USB IDs. OBJECTIVE DEVELOPMENT furnishes you with one or two USB
+Product ID(s), sent to you in e-mail. These Product IDs are reserved
+exclusively for you. OBJECTIVE DEVELOPMENT has obtained USB Product ID
+ranges under the Vendor ID 5824 from Wouter van Ooijen (Van Ooijen
+Technische Informatica, www.voti.nl) and under the Vendor ID 8352 from
+Jason Kotzin (now flirc.tv, Inc.). Both owners of the Vendor IDs have
+obtained these IDs from the USB Implementers Forum, Inc. (www.usb.org).
+OBJECTIVE DEVELOPMENT disclaims all liability which might arise from the
+assignment of USB IDs.
+
+2.5 USB Certification. Although not part of this agreement, we want to make
+it clear that you cannot become USB certified when you use V-USB or a USB
+Product ID assigned by OBJECTIVE DEVELOPMENT. AVR microcontrollers don't
+meet the electrical specifications required by the USB specification and
+the USB Implementers Forum certifies only members who bought a Vendor ID of
+their own.
+
+
+3 LICENSE RESTRICTIONS
+
+3.1 Number of Units. Only one of the following three definitions is
+applicable. Which one is determined by the amount you pay to OBJECTIVE
+DEVELOPMENT, see section 4 ("Payment") below.
+
+Hobby License: You may use V-USB according to section 2 above in no more
+than 5 hardware units. These units must not be sold for profit.
+
+Entry Level License: You may use V-USB according to section 2 above in no
+more than 150 hardware units.
+
+Professional License: You may use V-USB according to section 2 above in
+any number of hardware units, except for large scale production ("unlimited
+fair use"). Quantities below 10,000 units are not considered large scale
+production. If your reach quantities which are obviously large scale
+production, you must pay a license fee of 0.10 EUR per unit for all units
+above 10,000.
+
+3.2 Rental. You may not rent, lease, or lend V-USB or otherwise encumber
+any copy of V-USB, or any of the rights granted herein.
+
+3.3 Transfer. You may not transfer your rights under this Agreement to
+another party without OBJECTIVE DEVELOPMENT's prior written consent. If
+such consent is obtained, you may permanently transfer this License to
+another party. The recipient of such transfer must agree to all terms and
+conditions of this Agreement.
+
+3.4 Reservation of Rights. OBJECTIVE DEVELOPMENT retains all rights not
+expressly granted.
+
+3.5 Non-Exclusive Rights. Your license rights under this Agreement are
+non-exclusive.
+
+3.6 Third Party Rights. This Agreement cannot grant you rights controlled
+by third parties. In particular, you are not allowed to use the USB logo or
+other trademarks owned by the USB Implementers Forum, Inc. without their
+consent. Since such consent depends on USB certification, it should be
+noted that V-USB will not pass certification because it does not
+implement checksum verification and the microcontroller ports do not meet
+the electrical specifications.
+
+
+4 PAYMENT
+
+The payment amount depends on the variation of this agreement (according to
+section 3.1) into which you want to enter. Concrete prices are listed on
+OBJECTIVE DEVELOPMENT's web site, usually at
+http://www.obdev.at/vusb/license.html. You agree to pay the amount listed
+there to OBJECTIVE DEVELOPMENT or OBJECTIVE DEVELOPMENT's payment processor
+or reseller.
+
+
+5 COPYRIGHT AND OWNERSHIP
+
+V-USB is protected by copyright laws and international copyright
+treaties, as well as other intellectual property laws and treaties. V-USB
+is licensed, not sold.
+
+
+6 TERM AND TERMINATION
+
+6.1 Term. This Agreement shall continue indefinitely. However, OBJECTIVE
+DEVELOPMENT may terminate this Agreement and revoke the granted license and
+USB-IDs if you fail to comply with any of its terms and conditions.
+
+6.2 Survival of Terms. All provisions regarding secrecy, confidentiality
+and limitation of liability shall survive termination of this agreement.
+
+
+7 DISCLAIMER OF WARRANTY AND LIABILITY
+
+LIMITED WARRANTY. V-USB IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+KIND. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, OBJECTIVE
+DEVELOPMENT AND ITS SUPPLIERS HEREBY DISCLAIM ALL WARRANTIES, EITHER
+EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND
+NON-INFRINGEMENT, WITH REGARD TO V-USB, AND THE PROVISION OF OR FAILURE
+TO PROVIDE SUPPORT SERVICES. THIS LIMITED WARRANTY GIVES YOU SPECIFIC LEGAL
+RIGHTS. YOU MAY HAVE OTHERS, WHICH VARY FROM STATE/JURISDICTION TO
+STATE/JURISDICTION.
+
+LIMITATION OF LIABILITY. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW,
+IN NO EVENT SHALL OBJECTIVE DEVELOPMENT OR ITS SUPPLIERS BE LIABLE FOR ANY
+SPECIAL, INCIDENTAL, INDIRECT, OR CONSEQUENTIAL DAMAGES WHATSOEVER
+(INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS,
+BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR ANY OTHER PECUNIARY
+LOSS) ARISING OUT OF THE USE OF OR INABILITY TO USE V-USB OR THE
+PROVISION OF OR FAILURE TO PROVIDE SUPPORT SERVICES, EVEN IF OBJECTIVE
+DEVELOPMENT HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. IN ANY
+CASE, OBJECTIVE DEVELOPMENT'S ENTIRE LIABILITY UNDER ANY PROVISION OF THIS
+AGREEMENT SHALL BE LIMITED TO THE AMOUNT ACTUALLY PAID BY YOU FOR V-USB.
+
+
+8 MISCELLANEOUS TERMS
+
+8.1 Marketing. OBJECTIVE DEVELOPMENT has the right to mention for marketing
+purposes that you entered into this agreement.
+
+8.2 Entire Agreement. This document represents the entire agreement between
+OBJECTIVE DEVELOPMENT and you. It may only be modified in writing signed by
+an authorized representative of both, OBJECTIVE DEVELOPMENT and you.
+
+8.3 Severability. In case a provision of these terms and conditions should
+be or become partly or entirely invalid, ineffective, or not executable,
+the validity of all other provisions shall not be affected.
+
+8.4 Applicable Law. This agreement is governed by the laws of the Republic
+of Austria.
+
+8.5 Responsible Courts. The responsible courts in Vienna/Austria will have
+exclusive jurisdiction regarding all disputes in connection with this
+agreement.
+
--- /dev/null
+OBJECTIVE DEVELOPMENT GmbH's V-USB driver software is distributed under the
+terms and conditions of the GNU GPL version 2 or the GNU GPL version 3. It is
+your choice whether you apply the terms of version 2 or version 3. The full
+text of GPLv2 is included below. In addition to the requirements in the GPL,
+we STRONGLY ENCOURAGE you to do the following:
+
+(1) Publish your entire project on a web site and drop us a note with the URL.
+Use the form at http://www.obdev.at/vusb/feedback.html for your submission.
+
+(2) Adhere to minimum publication standards. Please include AT LEAST:
+ - a circuit diagram in PDF, PNG or GIF format
+ - full source code for the host software
+ - a Readme.txt file in ASCII format which describes the purpose of the
+ project and what can be found in which directories and which files
+ - a reference to http://www.obdev.at/vusb/
+
+(3) If you improve the driver firmware itself, please give us a free license
+to your modifications for our commercial license offerings.
+
+
+
+ GNU GENERAL PUBLIC LICENSE
+ Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+ 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.) You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+ To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
+rights.
+
+ We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+ Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+ Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+\f
+ GNU GENERAL PUBLIC LICENSE
+ TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+ 0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License. The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language. (Hereinafter, translation is included without limitation in
+the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+ 1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+ 2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+ a) You must cause the modified files to carry prominent notices
+ stating that you changed the files and the date of any change.
+
+ b) You must cause any work that you distribute or publish, that in
+ whole or in part contains or is derived from the Program or any
+ part thereof, to be licensed as a whole at no charge to all third
+ parties under the terms of this License.
+
+ c) If the modified program normally reads commands interactively
+ when run, you must cause it, when started running for such
+ interactive use in the most ordinary way, to print or display an
+ announcement including an appropriate copyright notice and a
+ notice that there is no warranty (or else, saying that you provide
+ a warranty) and that users may redistribute the program under
+ these conditions, and telling the user how to view a copy of this
+ License. (Exception: if the Program itself is interactive but
+ does not normally print such an announcement, your work based on
+ the Program is not required to print an announcement.)
+\f
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+ 3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+ a) Accompany it with the complete corresponding machine-readable
+ source code, which must be distributed under the terms of Sections
+ 1 and 2 above on a medium customarily used for software interchange; or,
+
+ b) Accompany it with a written offer, valid for at least three
+ years, to give any third party, for a charge no more than your
+ cost of physically performing source distribution, a complete
+ machine-readable copy of the corresponding source code, to be
+ distributed under the terms of Sections 1 and 2 above on a medium
+ customarily used for software interchange; or,
+
+ c) Accompany it with the information you received as to the offer
+ to distribute corresponding source code. (This alternative is
+ allowed only for noncommercial distribution and only if you
+ received the program in object code or executable form with such
+ an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
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+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+\f
+ 4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+ 5. You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+ 6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+ 7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+\f
+ 8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+ 9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation. If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+ 10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission. For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this. Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+ NO WARRANTY
+
+ 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+ 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+ END OF TERMS AND CONDITIONS
+\f
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+ Gnomovision version 69, Copyright (C) year name of author
+ Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+ `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+ <signature of Ty Coon>, 1 April 1989
+ Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs. If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library. If this is what you want to do, use the GNU Library General
+Public License instead of this License.
--- /dev/null
+This is the Readme file to Objective Development's firmware-only USB driver
+for Atmel AVR microcontrollers. For more information please visit
+http://www.obdev.at/vusb/
+
+This directory contains the USB firmware only. Copy it as-is to your own
+project and add all .c and .S files to your project (these files are marked
+with an asterisk in the list below). Then copy usbconfig-prototype.h as
+usbconfig.h to your project and edit it according to your configuration.
+
+
+TECHNICAL DOCUMENTATION
+=======================
+The technical documentation (API) for the firmware driver is contained in the
+file "usbdrv.h". Please read all of it carefully! Configuration options are
+documented in "usbconfig-prototype.h".
+
+The driver consists of the following files:
+ Readme.txt ............. The file you are currently reading.
+ Changelog.txt .......... Release notes for all versions of the driver.
+ usbdrv.h ............... Driver interface definitions and technical docs.
+* usbdrv.c ............... High level language part of the driver. Link this
+ module to your code!
+* usbdrvasm.S ............ Assembler part of the driver. This module is mostly
+ a stub and includes one of the usbdrvasm*.S files
+ depending on processor clock. Link this module to
+ your code!
+ usbdrvasm*.inc ......... Assembler routines for particular clock frequencies.
+ Included by usbdrvasm.S, don't link it directly!
+ asmcommon.inc .......... Common assembler routines. Included by
+ usbdrvasm*.inc, don't link it directly!
+ usbconfig-prototype.h .. Prototype for your own usbdrv.h file.
+* oddebug.c .............. Debug functions. Only used when DEBUG_LEVEL is
+ defined to a value greater than 0. Link this module
+ to your code!
+ oddebug.h .............. Interface definitions of the debug module.
+ usbportability.h ....... Header with compiler-dependent stuff.
+ usbdrvasm.asm .......... Compatibility stub for IAR-C-compiler. Use this
+ module instead of usbdrvasm.S when you assembler
+ with IAR's tools.
+ License.txt ............ Open Source license for this driver.
+ CommercialLicense.txt .. Optional commercial license for this driver.
+ USB-ID-FAQ.txt ......... General infos about USB Product- and Vendor-IDs.
+ USB-IDs-for-free.txt ... List and terms of use for free shared PIDs.
+
+(*) ... These files should be linked to your project.
+
+
+CPU CORE CLOCK FREQUENCY
+========================
+We supply assembler modules for clock frequencies of 12 MHz, 12.8 MHz, 15 MHz,
+16 MHz, 16.5 MHz 18 MHz and 20 MHz. Other clock rates are not supported. The
+actual clock rate must be configured in usbconfig.h.
+
+12 MHz Clock
+This is the traditional clock rate of V-USB because it's the lowest clock
+rate where the timing constraints of the USB spec can be met.
+
+15 MHz Clock
+Similar to 12 MHz, but some NOPs inserted. On the other hand, the higher clock
+rate allows for some loops which make the resulting code size somewhat smaller
+than the 12 MHz version.
+
+16 MHz Clock
+This clock rate has been added for users of the Arduino board and other
+ready-made boards which come with a fixed 16 MHz crystal. It's also an option
+if you need the slightly higher clock rate for performance reasons. Since
+16 MHz is not divisible by the USB low speed bit clock of 1.5 MHz, the code
+is somewhat tricky and has to insert a leap cycle every third byte.
+
+12.8 MHz and 16.5 MHz Clock
+The assembler modules for these clock rates differ from the other modules
+because they have been built for an RC oscillator with only 1% precision. The
+receiver code inserts leap cycles to compensate for clock deviations. 1% is
+also the precision which can be achieved by calibrating the internal RC
+oscillator of the AVR. Please note that only AVRs with internal 64 MHz PLL
+oscillator can reach 16.5 MHz with the RC oscillator. This includes the very
+popular ATTiny25, ATTiny45, ATTiny85 series as well as the ATTiny26. Almost
+all AVRs can reach 12.8 MHz, although this is outside the specified range.
+
+See the EasyLogger example at http://www.obdev.at/vusb/easylogger.html for
+code which calibrates the RC oscillator based on the USB frame clock.
+
+18 MHz Clock
+This module is closer to the USB specification because it performs an on the
+fly CRC check for incoming packets. Packets with invalid checksum are
+discarded as required by the spec. If you also implement checks for data
+PID toggling on application level (see option USB_CFG_CHECK_DATA_TOGGLING
+in usbconfig.h for more info), this ensures data integrity. Due to the CRC
+tables and alignment requirements, this code is bigger than modules for other
+clock rates. To activate this module, you must define USB_CFG_CHECK_CRC to 1
+and USB_CFG_CLOCK_KHZ to 18000 in usbconfig.h.
+
+20 MHz Clock
+This module is for people who won't do it with less than the maximum. Since
+20 MHz is not divisible by the USB low speed bit clock of 1.5 MHz, the code
+uses similar tricks as the 16 MHz module to insert leap cycles.
+
+
+USB IDENTIFIERS
+===============
+Every USB device needs a vendor- and a product-identifier (VID and PID). VIDs
+are obtained from usb.org for a price of 1,500 USD. Once you have a VID, you
+can assign PIDs at will.
+
+Since an entry level cost of 1,500 USD is too high for most small companies
+and hobbyists, we provide some VID/PID pairs for free. See the file
+USB-IDs-for-free.txt for details.
+
+Objective Development also has some license offerings which include product
+IDs. See http://www.obdev.at/vusb/ for details.
+
+
+DEVELOPMENT SYSTEM
+==================
+This driver has been developed and optimized for the GNU compiler version 3
+and 4. We recommend that you use the GNU compiler suite because it is freely
+available. V-USB has also been ported to the IAR compiler and assembler. It
+has been tested with IAR 4.10B/W32 and 4.12A/W32 on an ATmega8 with the
+"small" and "tiny" memory model. Not every release is tested with IAR CC and
+the driver may therefore fail to compile with IAR. Please note that gcc is
+more efficient for usbdrv.c because this module has been deliberately
+optimized for gcc.
+
+Gcc version 3 produces smaller code than version 4 due to new optimizing
+capabilities which don't always improve things on 8 bit CPUs. The code size
+generated by gcc 4 can be reduced with the compiler options
+-fno-move-loop-invariants, -fno-tree-scev-cprop and
+-fno-inline-small-functions in addition to -Os. On devices with more than
+8k of flash memory, we also recommend the linker option --relax (written as
+-Wl,--relax for gcc) to convert absolute calls into relative where possible.
+
+For more information about optimizing options see:
+
+ http://www.tty1.net/blog/2008-04-29-avr-gcc-optimisations_en.html
+
+These optimizations are good for gcc 4.x. Version 3.x of gcc does not support
+most of these options and produces good code anyway.
+
+
+USING V-USB FOR FREE
+====================
+The AVR firmware driver is published under the GNU General Public License
+Version 2 (GPL2) and the GNU General Public License Version 3 (GPL3). It is
+your choice whether you apply the terms of version 2 or version 3.
+
+If you decide for the free GPL2 or GPL3, we STRONGLY ENCOURAGE you to do the
+following things IN ADDITION to the obligations from the GPL:
+
+(1) Publish your entire project on a web site and drop us a note with the URL.
+Use the form at http://www.obdev.at/vusb/feedback.html for your submission.
+If you don't have a web site, you can publish the project in obdev's
+documentation wiki at
+http://www.obdev.at/goto.php?t=vusb-wiki&p=hosted-projects.
+
+(2) Adhere to minimum publication standards. Please include AT LEAST:
+ - a circuit diagram in PDF, PNG or GIF format
+ - full source code for the host software
+ - a Readme.txt file in ASCII format which describes the purpose of the
+ project and what can be found in which directories and which files
+ - a reference to http://www.obdev.at/vusb/
+
+(3) If you improve the driver firmware itself, please give us a free license
+to your modifications for our commercial license offerings.
+
+
+COMMERCIAL LICENSES FOR V-USB
+=============================
+If you don't want to publish your source code under the terms of the GPL,
+you can simply pay money for V-USB. As an additional benefit you get
+USB PIDs for free, reserved exclusively to you. See the file
+"CommercialLicense.txt" for details.
+
--- /dev/null
+Version 2012-07-09
+
+==========================
+WHY DO WE NEED THESE IDs?
+==========================
+
+USB is more than a low level protocol for data transport. It also defines a
+common set of requests which must be understood by all devices. And as part
+of these common requests, the specification defines data structures, the
+USB Descriptors, which are used to describe the properties of the device.
+
+From the perspective of an operating system, it is therefore possible to find
+out basic properties of a device (such as e.g. the manufacturer and the name
+of the device) without a device-specific driver. This is essential because
+the operating system can choose a driver to load based on this information
+(Plug-And-Play).
+
+Among the most important properties in the Device Descriptor are the USB
+Vendor- and Product-ID. Both are 16 bit integers. The most simple form of
+driver matching is based on these IDs. The driver announces the Vendor- and
+Product-IDs of the devices it can handle and the operating system loads the
+appropriate driver when the device is connected.
+
+It is obvious that this technique only works if the pair Vendor- plus
+Product-ID is unique: Only devices which require the same driver can have the
+same pair of IDs.
+
+
+=====================================================
+HOW DOES THE USB STANDARD ENSURE THAT IDs ARE UNIQUE?
+=====================================================
+
+Since it is so important that USB IDs are unique, the USB Implementers Forum,
+Inc. (usb.org) needs a way to enforce this legally. It is not forbidden by
+law to build a device and assign it any random numbers as IDs. Usb.org
+therefore needs an agreement to regulate the use of USB IDs. The agreement
+binds only parties who agreed to it, of course. Everybody else is free to use
+any numbers for their IDs.
+
+So how can usb.org ensure that every manufacturer of USB devices enters into
+an agreement with them? They do it via trademark licensing. Usb.org has
+registered the trademark "USB", all associated logos and related terms. If
+you want to put an USB logo on your product or claim that it is USB
+compliant, you must license these trademarks from usb.org. And this is where
+you enter into an agreement. See the "USB-IF Trademark License Agreement and
+Usage Guidelines for the USB-IF Logo" at
+http://www.usb.org/developers/logo_license/.
+
+Licensing the USB trademarks requires that you buy a USB Vendor-ID from
+usb.org (one-time fee of ca. 2,000 USD), that you become a member of usb.org
+(yearly fee of ca. 4,000 USD) and that you meet all the technical
+specifications from the USB spec.
+
+This means that most hobbyists and small companies will never be able to
+become USB compliant, just because membership is so expensive. And you can't
+be compliant with a driver based on V-USB anyway, because the AVR's port pins
+don't meet the electrical specifications for USB. So, in principle, all
+hobbyists and small companies are free to choose any random numbers for their
+IDs. They have nothing to lose...
+
+There is one exception worth noting, though: If you use a sub-component which
+implements USB, the vendor of the sub-components may guarantee USB
+compliance. This might apply to some or all of FTDI's solutions.
+
+
+=======================================================================
+WHY SHOULD YOU OBTAIN USB IDs EVEN IF YOU DON'T LICENSE USB TRADEMARKS?
+=======================================================================
+
+You have learned in the previous section that you are free to choose any
+numbers for your IDs anyway. So why not do exactly this? There is still the
+technical issue. If you choose IDs which are already in use by somebody else,
+operating systems will load the wrong drivers and your device won't work.
+Even if you choose IDs which are not currently in use, they may be in use in
+the next version of the operating system or even after an automatic update.
+
+So what you need is a pair of Vendor- and Product-IDs for which you have the
+guarantee that no USB compliant product uses them. This implies that no
+operating system will ever ship with drivers responsible for these IDs.
+
+
+==============================================
+HOW DOES OBJECTIVE DEVELOPMENT HANDLE USB IDs?
+==============================================
+
+Objective Development gives away pairs of USB-IDs with their V-USB licenses.
+In order to ensure that these IDs are unique, Objective Development has an
+agreement with the company/person who has bought the USB Vendor-ID from
+usb.org. This agreement ensures that a range of USB Product-IDs is reserved
+for assignment by Objective Development and that the owner of the Vendor-ID
+won't give it to anybody else.
+
+This means that you have to trust three parties to ensure uniqueness of
+your IDs:
+
+ - Objective Development, that they don't give the same PID to more than
+ one person.
+ - The owner of the Vendor-ID that they don't assign PIDs from the range
+ assigned to Objective Development to anybody else.
+ - Usb.org that they don't assign the same Vendor-ID a second time.
+
+
+==================================
+WHO IS THE OWNER OF THE VENDOR-ID?
+==================================
+
+Objective Development has obtained ranges of USB Product-IDs under two
+Vendor-IDs: Under Vendor-ID 5824 from Wouter van Ooijen (Van Ooijen
+Technische Informatica, www.voti.nl) and under Vendor-ID 8352 from Jason
+Kotzin (now flirc.tv, Inc.). Both VID owners have received their Vendor-ID
+directly from usb.org.
+
+
+=========================================================================
+CAN I USE USB-IDs FROM OBJECTIVE DEVELOPMENT WITH OTHER DRIVERS/HARDWARE?
+=========================================================================
+
+The short answer is: Yes. All you get is a guarantee that the IDs are never
+assigned to anybody else. What more do you need?
+
+
+============================
+WHAT ABOUT SHARED ID PAIRS?
+============================
+
+Objective Development has reserved some PID/VID pairs for shared use. You
+have no guarantee of uniqueness for them, except that no USB compliant device
+uses them. In order to avoid technical problems, we must ensure that all
+devices with the same pair of IDs use the same driver on kernel level. For
+details, see the file USB-IDs-for-free.txt.
+
+
+======================================================
+I HAVE HEARD THAT SUB-LICENSING OF USB-IDs IS ILLEGAL?
+======================================================
+
+A 16 bit integer number cannot be protected by copyright laws. It is not
+sufficiently complex. And since none of the parties involved entered into the
+USB-IF Trademark License Agreement, we are not bound by this agreement. So
+there is no reason why it should be illegal to sub-license USB-IDs.
+
+
+=============================================
+WHO IS LIABLE IF THERE ARE INCOMPATIBILITIES?
+=============================================
+
+Objective Development disclaims all liabilities which might arise from the
+assignment of IDs. If you guarantee product features to your customers
+without proper disclaimer, YOU are liable for that.
--- /dev/null
+Version 2009-08-22
+
+===========================
+FREE USB-IDs FOR SHARED USE
+===========================
+
+Objective Development has reserved a set of USB Product-IDs for use according
+to the guidelines outlined below. For more information about the concept of
+USB IDs please see the file USB-ID-FAQ.txt. Objective Development guarantees
+that the IDs listed below are not used by any USB compliant devices.
+
+
+====================
+MECHANISM OF SHARING
+====================
+
+From a technical point of view, two different devices can share the same USB
+Vendor- and Product-ID if they require the same driver on operating system
+level. We make use of this fact by assigning separate IDs for various device
+classes. On application layer, devices must be distinguished by their textual
+name or serial number. We offer separate sets of IDs for discrimination by
+textual name and for serial number.
+
+Examples for shared use of USB IDs are included with V-USB in the "examples"
+subdirectory.
+
+
+======================================
+IDs FOR DISCRIMINATION BY TEXTUAL NAME
+======================================
+
+If you use one of the IDs listed below, your device and host-side software
+must conform to these rules:
+
+(1) The USB device MUST provide a textual representation of the manufacturer
+and product identification. The manufacturer identification MUST be available
+at least in USB language 0x0409 (English/US).
+
+(2) The textual manufacturer identification MUST contain either an Internet
+domain name (e.g. "mycompany.com") registered and owned by you, or an e-mail
+address under your control (e.g. "myname@gmx.net"). You can embed the domain
+name or e-mail address in any string you like, e.g. "Objective Development
+http://www.obdev.at/vusb/".
+
+(3) You are responsible for retaining ownership of the domain or e-mail
+address for as long as any of your products are in use.
+
+(4) You may choose any string for the textual product identification, as long
+as this string is unique within the scope of your textual manufacturer
+identification.
+
+(5) Application side device look-up MUST be based on the textual manufacturer
+and product identification in addition to VID/PID matching. The driver
+matching MUST be a comparison of the entire strings, NOT a sub-string match.
+
+(6) For devices which implement a particular USB device class (e.g. HID), the
+operating system's default class driver MUST be used. If an operating system
+driver for Vendor Class devices is needed, this driver must be libusb or
+libusb-win32 (see http://libusb.org/ and
+http://libusb-win32.sourceforge.net/).
+
+Table if IDs for discrimination by textual name:
+
+PID dec (hex) | VID dec (hex) | Description of use
+==============+===============+============================================
+1500 (0x05dc) | 5824 (0x16c0) | For Vendor Class devices with libusb
+--------------+---------------+--------------------------------------------
+1503 (0x05df) | 5824 (0x16c0) | For generic HID class devices (which are
+ | | NOT mice, keyboards or joysticks)
+--------------+---------------+--------------------------------------------
+1505 (0x05e1) | 5824 (0x16c0) | For CDC-ACM class devices (modems)
+--------------+---------------+--------------------------------------------
+1508 (0x05e4) | 5824 (0x16c0) | For MIDI class devices
+--------------+---------------+--------------------------------------------
+
+Note that Windows caches the textual product- and vendor-description for
+mice, keyboards and joysticks. Name-bsed discrimination is therefore not
+recommended for these device classes.
+
+
+=======================================
+IDs FOR DISCRIMINATION BY SERIAL NUMBER
+=======================================
+
+If you use one of the IDs listed below, your device and host-side software
+must conform to these rules:
+
+(1) The USB device MUST provide a textual representation of the serial
+number, unless ONLY the operating system's default class driver is used.
+The serial number string MUST be available at least in USB language 0x0409
+(English/US).
+
+(2) The serial number MUST start with either an Internet domain name (e.g.
+"mycompany.com") registered and owned by you, or an e-mail address under your
+control (e.g. "myname@gmx.net"), both terminated with a colon (":") character.
+You MAY append any string you like for further discrimination of your devices.
+
+(3) You are responsible for retaining ownership of the domain or e-mail
+address for as long as any of your products are in use.
+
+(5) Application side device look-up MUST be based on the serial number string
+in addition to VID/PID matching. The matching must start at the first
+character of the serial number string and include the colon character
+terminating your domain or e-mail address. It MAY stop anywhere after that.
+
+(6) For devices which implement a particular USB device class (e.g. HID), the
+operating system's default class driver MUST be used. If an operating system
+driver for Vendor Class devices is needed, this driver must be libusb or
+libusb-win32 (see http://libusb.org/ and
+http://libusb-win32.sourceforge.net/).
+
+(7) If ONLY the operating system's default class driver is used, e.g. for
+mice, keyboards, joysticks, CDC or MIDI devices and no discrimination by an
+application is needed, the serial number may be omitted.
+
+
+Table if IDs for discrimination by serial number string:
+
+PID dec (hex) | VID dec (hex) | Description of use
+===============+===============+===========================================
+10200 (0x27d8) | 5824 (0x16c0) | For Vendor Class devices with libusb
+---------------+---------------+-------------------------------------------
+10201 (0x27d9) | 5824 (0x16c0) | For generic HID class devices (which are
+ | | NOT mice, keyboards or joysticks)
+---------------+---------------+-------------------------------------------
+10202 (0x27da) | 5824 (0x16c0) | For USB Mice
+---------------+---------------+-------------------------------------------
+10203 (0x27db) | 5824 (0x16c0) | For USB Keyboards
+---------------+---------------+-------------------------------------------
+10204 (0x27dc) | 5824 (0x16c0) | For USB Joysticks
+---------------+---------------+-------------------------------------------
+10205 (0x27dd) | 5824 (0x16c0) | For CDC-ACM class devices (modems)
+---------------+---------------+-------------------------------------------
+10206 (0x27de) | 5824 (0x16c0) | For MIDI class devices
+---------------+---------------+-------------------------------------------
+
+
+=================
+ORIGIN OF USB-IDs
+=================
+
+OBJECTIVE DEVELOPMENT Software GmbH has obtained all VID/PID pairs listed
+here from Wouter van Ooijen (see www.voti.nl) for exclusive disposition.
+Wouter van Ooijen has obtained the VID from the USB Implementers Forum, Inc.
+(see www.usb.org). The VID is registered for the company name "Van Ooijen
+Technische Informatica".
+
+
+==========
+DISCLAIMER
+==========
+
+OBJECTIVE DEVELOPMENT Software GmbH disclaims all liability for any
+problems which are caused by the shared use of these VID/PID pairs.
--- /dev/null
+/* Name: asmcommon.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2007-11-05
+ * Tabsize: 4
+ * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file contains assembler code which is shared among the USB driver
+implementations for different CPU cocks. Since the code must be inserted
+in the middle of the module, it's split out into this file and #included.
+
+Jump destinations called from outside:
+ sofError: Called when no start sequence was found.
+ se0: Called when a package has been successfully received.
+ overflow: Called when receive buffer overflows.
+ doReturn: Called after sending data.
+
+Outside jump destinations used by this module:
+ waitForJ: Called to receive an already arriving packet.
+ sendAckAndReti:
+ sendNakAndReti:
+ sendCntAndReti:
+ usbSendAndReti:
+
+The following macros must be defined before this file is included:
+ .macro POP_STANDARD
+ .endm
+ .macro POP_RETI
+ .endm
+*/
+
+#define token x1
+
+overflow:
+ ldi x2, 1<<USB_INTR_PENDING_BIT
+ USB_STORE_PENDING(x2) ; clear any pending interrupts
+ignorePacket:
+ clr token
+ rjmp storeTokenAndReturn
+
+;----------------------------------------------------------------------------
+; Processing of received packet (numbers in brackets are cycles after center of SE0)
+;----------------------------------------------------------------------------
+;This is the only non-error exit point for the software receiver loop
+;we don't check any CRCs here because there is no time left.
+se0:
+ subi cnt, USB_BUFSIZE ;[5]
+ neg cnt ;[6]
+ sub YL, cnt ;[7]
+ sbci YH, 0 ;[8]
+ ldi x2, 1<<USB_INTR_PENDING_BIT ;[9]
+ USB_STORE_PENDING(x2) ;[10] clear pending intr and check flag later. SE0 should be over.
+ ld token, y ;[11]
+ cpi token, USBPID_DATA0 ;[13]
+ breq handleData ;[14]
+ cpi token, USBPID_DATA1 ;[15]
+ breq handleData ;[16]
+ lds shift, usbDeviceAddr;[17]
+ ldd x2, y+1 ;[19] ADDR and 1 bit endpoint number
+ lsl x2 ;[21] shift out 1 bit endpoint number
+ cpse x2, shift ;[22]
+ rjmp ignorePacket ;[23]
+/* only compute endpoint number in x3 if required later */
+#if USB_CFG_HAVE_INTRIN_ENDPOINT || USB_CFG_IMPLEMENT_FN_WRITEOUT
+ ldd x3, y+2 ;[24] endpoint number + crc
+ rol x3 ;[26] shift in LSB of endpoint
+#endif
+ cpi token, USBPID_IN ;[27]
+ breq handleIn ;[28]
+ cpi token, USBPID_SETUP ;[29]
+ breq handleSetupOrOut ;[30]
+ cpi token, USBPID_OUT ;[31]
+ brne ignorePacket ;[32] must be ack, nak or whatever
+; rjmp handleSetupOrOut ; fallthrough
+
+;Setup and Out are followed by a data packet two bit times (16 cycles) after
+;the end of SE0. The sync code allows up to 40 cycles delay from the start of
+;the sync pattern until the first bit is sampled. That's a total of 56 cycles.
+handleSetupOrOut: ;[32]
+#if USB_CFG_IMPLEMENT_FN_WRITEOUT /* if we have data for endpoint != 0, set usbCurrentTok to address */
+ andi x3, 0xf ;[32]
+ breq storeTokenAndReturn ;[33]
+ mov token, x3 ;[34] indicate that this is endpoint x OUT
+#endif
+storeTokenAndReturn:
+ sts usbCurrentTok, token;[35]
+doReturn:
+ POP_STANDARD ;[37] 12...16 cycles
+ USB_LOAD_PENDING(YL) ;[49]
+ sbrc YL, USB_INTR_PENDING_BIT;[50] check whether data is already arriving
+ rjmp waitForJ ;[51] save the pops and pushes -- a new interrupt is already pending
+sofError:
+ POP_RETI ;macro call
+ reti
+
+handleData:
+#if USB_CFG_CHECK_CRC
+ CRC_CLEANUP_AND_CHECK ; jumps to ignorePacket if CRC error
+#endif
+ lds shift, usbCurrentTok;[18]
+ tst shift ;[20]
+ breq doReturn ;[21]
+ lds x2, usbRxLen ;[22]
+ tst x2 ;[24]
+ brne sendNakAndReti ;[25]
+; 2006-03-11: The following two lines fix a problem where the device was not
+; recognized if usbPoll() was called less frequently than once every 4 ms.
+ cpi cnt, 4 ;[26] zero sized data packets are status phase only -- ignore and ack
+ brmi sendAckAndReti ;[27] keep rx buffer clean -- we must not NAK next SETUP
+#if USB_CFG_CHECK_DATA_TOGGLING
+ sts usbCurrentDataToken, token ; store for checking by C code
+#endif
+ sts usbRxLen, cnt ;[28] store received data, swap buffers
+ sts usbRxToken, shift ;[30]
+ lds x2, usbInputBufOffset;[32] swap buffers
+ ldi cnt, USB_BUFSIZE ;[34]
+ sub cnt, x2 ;[35]
+ sts usbInputBufOffset, cnt;[36] buffers now swapped
+ rjmp sendAckAndReti ;[38] 40 + 17 = 57 until SOP
+
+handleIn:
+;We don't send any data as long as the C code has not processed the current
+;input data and potentially updated the output data. That's more efficient
+;in terms of code size than clearing the tx buffers when a packet is received.
+ lds x1, usbRxLen ;[30]
+ cpi x1, 1 ;[32] negative values are flow control, 0 means "buffer free"
+ brge sendNakAndReti ;[33] unprocessed input packet?
+ ldi x1, USBPID_NAK ;[34] prepare value for usbTxLen
+#if USB_CFG_HAVE_INTRIN_ENDPOINT
+ andi x3, 0xf ;[35] x3 contains endpoint
+#if USB_CFG_SUPPRESS_INTR_CODE
+ brne sendNakAndReti ;[36]
+#else
+ brne handleIn1 ;[36]
+#endif
+#endif
+ lds cnt, usbTxLen ;[37]
+ sbrc cnt, 4 ;[39] all handshake tokens have bit 4 set
+ rjmp sendCntAndReti ;[40] 42 + 16 = 58 until SOP
+ sts usbTxLen, x1 ;[41] x1 == USBPID_NAK from above
+ ldi YL, lo8(usbTxBuf) ;[43]
+ ldi YH, hi8(usbTxBuf) ;[44]
+ rjmp usbSendAndReti ;[45] 57 + 12 = 59 until SOP
+
+; Comment about when to set usbTxLen to USBPID_NAK:
+; We should set it back when we receive the ACK from the host. This would
+; be simple to implement: One static variable which stores whether the last
+; tx was for endpoint 0 or 1 and a compare in the receiver to distinguish the
+; ACK. However, we set it back immediately when we send the package,
+; assuming that no error occurs and the host sends an ACK. We save one byte
+; RAM this way and avoid potential problems with endless retries. The rest of
+; the driver assumes error-free transfers anyway.
+
+#if !USB_CFG_SUPPRESS_INTR_CODE && USB_CFG_HAVE_INTRIN_ENDPOINT /* placed here due to relative jump range */
+handleIn1: ;[38]
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+; 2006-06-10 as suggested by O.Tamura: support second INTR IN / BULK IN endpoint
+ cpi x3, USB_CFG_EP3_NUMBER;[38]
+ breq handleIn3 ;[39]
+#endif
+ lds cnt, usbTxLen1 ;[40]
+ sbrc cnt, 4 ;[42] all handshake tokens have bit 4 set
+ rjmp sendCntAndReti ;[43] 47 + 16 = 63 until SOP
+ sts usbTxLen1, x1 ;[44] x1 == USBPID_NAK from above
+ ldi YL, lo8(usbTxBuf1) ;[46]
+ ldi YH, hi8(usbTxBuf1) ;[47]
+ rjmp usbSendAndReti ;[48] 50 + 12 = 62 until SOP
+
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+handleIn3:
+ lds cnt, usbTxLen3 ;[41]
+ sbrc cnt, 4 ;[43]
+ rjmp sendCntAndReti ;[44] 49 + 16 = 65 until SOP
+ sts usbTxLen3, x1 ;[45] x1 == USBPID_NAK from above
+ ldi YL, lo8(usbTxBuf3) ;[47]
+ ldi YH, hi8(usbTxBuf3) ;[48]
+ rjmp usbSendAndReti ;[49] 51 + 12 = 63 until SOP
+#endif
+#endif
--- /dev/null
+/* Name: oddebug.c
+ * Project: AVR library
+ * Author: Christian Starkjohann
+ * Creation Date: 2005-01-16
+ * Tabsize: 4
+ * Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+#include "oddebug.h"
+
+#if DEBUG_LEVEL > 0
+
+#warning "Never compile production devices with debugging enabled"
+
+static void uartPutc(char c)
+{
+ while(!(ODDBG_USR & (1 << ODDBG_UDRE))); /* wait for data register empty */
+ ODDBG_UDR = c;
+}
+
+static uchar hexAscii(uchar h)
+{
+ h &= 0xf;
+ if(h >= 10)
+ h += 'a' - (uchar)10 - '0';
+ h += '0';
+ return h;
+}
+
+static void printHex(uchar c)
+{
+ uartPutc(hexAscii(c >> 4));
+ uartPutc(hexAscii(c));
+}
+
+void odDebug(uchar prefix, uchar *data, uchar len)
+{
+ printHex(prefix);
+ uartPutc(':');
+ while(len--){
+ uartPutc(' ');
+ printHex(*data++);
+ }
+ uartPutc('\r');
+ uartPutc('\n');
+}
+
+#endif
--- /dev/null
+/* Name: oddebug.h
+ * Project: AVR library
+ * Author: Christian Starkjohann
+ * Creation Date: 2005-01-16
+ * Tabsize: 4
+ * Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+#ifndef __oddebug_h_included__
+#define __oddebug_h_included__
+
+/*
+General Description:
+This module implements a function for debug logs on the serial line of the
+AVR microcontroller. Debugging can be configured with the define
+'DEBUG_LEVEL'. If this macro is not defined or defined to 0, all debugging
+calls are no-ops. If it is 1, DBG1 logs will appear, but not DBG2. If it is
+2, DBG1 and DBG2 logs will be printed.
+
+A debug log consists of a label ('prefix') to indicate which debug log created
+the output and a memory block to dump in hex ('data' and 'len').
+*/
+
+
+#ifndef F_CPU
+# define F_CPU 12000000 /* 12 MHz */
+#endif
+
+/* make sure we have the UART defines: */
+#include "usbportability.h"
+
+#ifndef uchar
+# define uchar unsigned char
+#endif
+
+#if DEBUG_LEVEL > 0 && !(defined TXEN || defined TXEN0) /* no UART in device */
+# warning "Debugging disabled because device has no UART"
+# undef DEBUG_LEVEL
+#endif
+
+#ifndef DEBUG_LEVEL
+# define DEBUG_LEVEL 0
+#endif
+
+/* ------------------------------------------------------------------------- */
+
+#if DEBUG_LEVEL > 0
+# define DBG1(prefix, data, len) odDebug(prefix, data, len)
+#else
+# define DBG1(prefix, data, len)
+#endif
+
+#if DEBUG_LEVEL > 1
+# define DBG2(prefix, data, len) odDebug(prefix, data, len)
+#else
+# define DBG2(prefix, data, len)
+#endif
+
+/* ------------------------------------------------------------------------- */
+
+#if DEBUG_LEVEL > 0
+extern void odDebug(uchar prefix, uchar *data, uchar len);
+
+/* Try to find our control registers; ATMEL likes to rename these */
+
+#if defined UBRR
+# define ODDBG_UBRR UBRR
+#elif defined UBRRL
+# define ODDBG_UBRR UBRRL
+#elif defined UBRR0
+# define ODDBG_UBRR UBRR0
+#elif defined UBRR0L
+# define ODDBG_UBRR UBRR0L
+#endif
+
+#if defined UCR
+# define ODDBG_UCR UCR
+#elif defined UCSRB
+# define ODDBG_UCR UCSRB
+#elif defined UCSR0B
+# define ODDBG_UCR UCSR0B
+#endif
+
+#if defined TXEN
+# define ODDBG_TXEN TXEN
+#else
+# define ODDBG_TXEN TXEN0
+#endif
+
+#if defined USR
+# define ODDBG_USR USR
+#elif defined UCSRA
+# define ODDBG_USR UCSRA
+#elif defined UCSR0A
+# define ODDBG_USR UCSR0A
+#endif
+
+#if defined UDRE
+# define ODDBG_UDRE UDRE
+#else
+# define ODDBG_UDRE UDRE0
+#endif
+
+#if defined UDR
+# define ODDBG_UDR UDR
+#elif defined UDR0
+# define ODDBG_UDR UDR0
+#endif
+
+static inline void odDebugInit(void)
+{
+ ODDBG_UCR |= (1<<ODDBG_TXEN);
+ ODDBG_UBRR = F_CPU / (19200 * 16L) - 1;
+}
+#else
+# define odDebugInit()
+#endif
+
+/* ------------------------------------------------------------------------- */
+
+#endif /* __oddebug_h_included__ */
--- /dev/null
+/* Name: usbconfig.h
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2005-04-01
+ * Tabsize: 4
+ * Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+#ifndef __usbconfig_h_included__
+#define __usbconfig_h_included__
+
+/*
+General Description:
+This file is an example configuration (with inline documentation) for the USB
+driver. It configures V-USB for USB D+ connected to Port D bit 2 (which is
+also hardware interrupt 0 on many devices) and USB D- to Port D bit 4. You may
+wire the lines to any other port, as long as D+ is also wired to INT0 (or any
+other hardware interrupt, as long as it is the highest level interrupt, see
+section at the end of this file).
++ To create your own usbconfig.h file, copy this file to your project's
++ firmware source directory) and rename it to "usbconfig.h".
++ Then edit it accordingly.
+*/
+
+/* ---------------------------- Hardware Config ---------------------------- */
+
+#define USB_CFG_IOPORTNAME D
+/* This is the port where the USB bus is connected. When you configure it to
+ * "B", the registers PORTB, PINB and DDRB will be used.
+ */
+#define USB_CFG_DMINUS_BIT 4
+/* This is the bit number in USB_CFG_IOPORT where the USB D- line is connected.
+ * This may be any bit in the port.
+ */
+#define USB_CFG_DPLUS_BIT 2
+/* This is the bit number in USB_CFG_IOPORT where the USB D+ line is connected.
+ * This may be any bit in the port. Please note that D+ must also be connected
+ * to interrupt pin INT0! [You can also use other interrupts, see section
+ * "Optional MCU Description" below, or you can connect D- to the interrupt, as
+ * it is required if you use the USB_COUNT_SOF feature. If you use D- for the
+ * interrupt, the USB interrupt will also be triggered at Start-Of-Frame
+ * markers every millisecond.]
+ */
+#define USB_CFG_CLOCK_KHZ (F_CPU/1000)
+/* Clock rate of the AVR in kHz. Legal values are 12000, 12800, 15000, 16000,
+ * 16500, 18000 and 20000. The 12.8 MHz and 16.5 MHz versions of the code
+ * require no crystal, they tolerate +/- 1% deviation from the nominal
+ * frequency. All other rates require a precision of 2000 ppm and thus a
+ * crystal!
+ * Since F_CPU should be defined to your actual clock rate anyway, you should
+ * not need to modify this setting.
+ */
+#define USB_CFG_CHECK_CRC 0
+/* Define this to 1 if you want that the driver checks integrity of incoming
+ * data packets (CRC checks). CRC checks cost quite a bit of code size and are
+ * currently only available for 18 MHz crystal clock. You must choose
+ * USB_CFG_CLOCK_KHZ = 18000 if you enable this option.
+ */
+
+/* ----------------------- Optional Hardware Config ------------------------ */
+
+/* #define USB_CFG_PULLUP_IOPORTNAME D */
+/* If you connect the 1.5k pullup resistor from D- to a port pin instead of
+ * V+, you can connect and disconnect the device from firmware by calling
+ * the macros usbDeviceConnect() and usbDeviceDisconnect() (see usbdrv.h).
+ * This constant defines the port on which the pullup resistor is connected.
+ */
+/* #define USB_CFG_PULLUP_BIT 4 */
+/* This constant defines the bit number in USB_CFG_PULLUP_IOPORT (defined
+ * above) where the 1.5k pullup resistor is connected. See description
+ * above for details.
+ */
+
+/* --------------------------- Functional Range ---------------------------- */
+
+#define USB_CFG_HAVE_INTRIN_ENDPOINT 0
+/* Define this to 1 if you want to compile a version with two endpoints: The
+ * default control endpoint 0 and an interrupt-in endpoint (any other endpoint
+ * number).
+ */
+#define USB_CFG_HAVE_INTRIN_ENDPOINT3 0
+/* Define this to 1 if you want to compile a version with three endpoints: The
+ * default control endpoint 0, an interrupt-in endpoint 3 (or the number
+ * configured below) and a catch-all default interrupt-in endpoint as above.
+ * You must also define USB_CFG_HAVE_INTRIN_ENDPOINT to 1 for this feature.
+ */
+#define USB_CFG_EP3_NUMBER 3
+/* If the so-called endpoint 3 is used, it can now be configured to any other
+ * endpoint number (except 0) with this macro. Default if undefined is 3.
+ */
+/* #define USB_INITIAL_DATATOKEN USBPID_DATA1 */
+/* The above macro defines the startup condition for data toggling on the
+ * interrupt/bulk endpoints 1 and 3. Defaults to USBPID_DATA1.
+ * Since the token is toggled BEFORE sending any data, the first packet is
+ * sent with the oposite value of this configuration!
+ */
+#define USB_CFG_IMPLEMENT_HALT 0
+/* Define this to 1 if you also want to implement the ENDPOINT_HALT feature
+ * for endpoint 1 (interrupt endpoint). Although you may not need this feature,
+ * it is required by the standard. We have made it a config option because it
+ * bloats the code considerably.
+ */
+#define USB_CFG_SUPPRESS_INTR_CODE 0
+/* Define this to 1 if you want to declare interrupt-in endpoints, but don't
+ * want to send any data over them. If this macro is defined to 1, functions
+ * usbSetInterrupt() and usbSetInterrupt3() are omitted. This is useful if
+ * you need the interrupt-in endpoints in order to comply to an interface
+ * (e.g. HID), but never want to send any data. This option saves a couple
+ * of bytes in flash memory and the transmit buffers in RAM.
+ */
+#define USB_CFG_INTR_POLL_INTERVAL 10
+/* If you compile a version with endpoint 1 (interrupt-in), this is the poll
+ * interval. The value is in milliseconds and must not be less than 10 ms for
+ * low speed devices.
+ */
+#define USB_CFG_IS_SELF_POWERED 0
+/* Define this to 1 if the device has its own power supply. Set it to 0 if the
+ * device is powered from the USB bus.
+ */
+#define USB_CFG_MAX_BUS_POWER 100
+/* Set this variable to the maximum USB bus power consumption of your device.
+ * The value is in milliamperes. [It will be divided by two since USB
+ * communicates power requirements in units of 2 mA.]
+ */
+#define USB_CFG_IMPLEMENT_FN_WRITE 0
+/* Set this to 1 if you want usbFunctionWrite() to be called for control-out
+ * transfers. Set it to 0 if you don't need it and want to save a couple of
+ * bytes.
+ */
+#define USB_CFG_IMPLEMENT_FN_READ 0
+/* Set this to 1 if you need to send control replies which are generated
+ * "on the fly" when usbFunctionRead() is called. If you only want to send
+ * data from a static buffer, set it to 0 and return the data from
+ * usbFunctionSetup(). This saves a couple of bytes.
+ */
+#define USB_CFG_IMPLEMENT_FN_WRITEOUT 0
+/* Define this to 1 if you want to use interrupt-out (or bulk out) endpoints.
+ * You must implement the function usbFunctionWriteOut() which receives all
+ * interrupt/bulk data sent to any endpoint other than 0. The endpoint number
+ * can be found in 'usbRxToken'.
+ */
+#define USB_CFG_HAVE_FLOWCONTROL 0
+/* Define this to 1 if you want flowcontrol over USB data. See the definition
+ * of the macros usbDisableAllRequests() and usbEnableAllRequests() in
+ * usbdrv.h.
+ */
+#define USB_CFG_DRIVER_FLASH_PAGE 0
+/* If the device has more than 64 kBytes of flash, define this to the 64 k page
+ * where the driver's constants (descriptors) are located. Or in other words:
+ * Define this to 1 for boot loaders on the ATMega128.
+ */
+#define USB_CFG_LONG_TRANSFERS 0
+/* Define this to 1 if you want to send/receive blocks of more than 254 bytes
+ * in a single control-in or control-out transfer. Note that the capability
+ * for long transfers increases the driver size.
+ */
+/* #define USB_RX_USER_HOOK(data, len) if(usbRxToken == (uchar)USBPID_SETUP) blinkLED(); */
+/* This macro is a hook if you want to do unconventional things. If it is
+ * defined, it's inserted at the beginning of received message processing.
+ * If you eat the received message and don't want default processing to
+ * proceed, do a return after doing your things. One possible application
+ * (besides debugging) is to flash a status LED on each packet.
+ */
+/* #define USB_RESET_HOOK(resetStarts) if(!resetStarts){hadUsbReset();} */
+/* This macro is a hook if you need to know when an USB RESET occurs. It has
+ * one parameter which distinguishes between the start of RESET state and its
+ * end.
+ */
+/* #define USB_SET_ADDRESS_HOOK() hadAddressAssigned(); */
+/* This macro (if defined) is executed when a USB SET_ADDRESS request was
+ * received.
+ */
+#define USB_COUNT_SOF 0
+/* define this macro to 1 if you need the global variable "usbSofCount" which
+ * counts SOF packets. This feature requires that the hardware interrupt is
+ * connected to D- instead of D+.
+ */
+/* #ifdef __ASSEMBLER__
+ * macro myAssemblerMacro
+ * in YL, TCNT0
+ * sts timer0Snapshot, YL
+ * endm
+ * #endif
+ * #define USB_SOF_HOOK myAssemblerMacro
+ * This macro (if defined) is executed in the assembler module when a
+ * Start Of Frame condition is detected. It is recommended to define it to
+ * the name of an assembler macro which is defined here as well so that more
+ * than one assembler instruction can be used. The macro may use the register
+ * YL and modify SREG. If it lasts longer than a couple of cycles, USB messages
+ * immediately after an SOF pulse may be lost and must be retried by the host.
+ * What can you do with this hook? Since the SOF signal occurs exactly every
+ * 1 ms (unless the host is in sleep mode), you can use it to tune OSCCAL in
+ * designs running on the internal RC oscillator.
+ * Please note that Start Of Frame detection works only if D- is wired to the
+ * interrupt, not D+. THIS IS DIFFERENT THAN MOST EXAMPLES!
+ */
+#define USB_CFG_CHECK_DATA_TOGGLING 0
+/* define this macro to 1 if you want to filter out duplicate data packets
+ * sent by the host. Duplicates occur only as a consequence of communication
+ * errors, when the host does not receive an ACK. Please note that you need to
+ * implement the filtering yourself in usbFunctionWriteOut() and
+ * usbFunctionWrite(). Use the global usbCurrentDataToken and a static variable
+ * for each control- and out-endpoint to check for duplicate packets.
+ */
+#define USB_CFG_HAVE_MEASURE_FRAME_LENGTH 0
+/* define this macro to 1 if you want the function usbMeasureFrameLength()
+ * compiled in. This function can be used to calibrate the AVR's RC oscillator.
+ */
+#define USB_USE_FAST_CRC 0
+/* The assembler module has two implementations for the CRC algorithm. One is
+ * faster, the other is smaller. This CRC routine is only used for transmitted
+ * messages where timing is not critical. The faster routine needs 31 cycles
+ * per byte while the smaller one needs 61 to 69 cycles. The faster routine
+ * may be worth the 32 bytes bigger code size if you transmit lots of data and
+ * run the AVR close to its limit.
+ */
+
+/* -------------------------- Device Description --------------------------- */
+
+#define USB_CFG_VENDOR_ID 0xc0, 0x16 /* = 0x16c0 = 5824 = voti.nl */
+/* USB vendor ID for the device, low byte first. If you have registered your
+ * own Vendor ID, define it here. Otherwise you may use one of obdev's free
+ * shared VID/PID pairs. Be sure to read USB-IDs-for-free.txt for rules!
+ * *** IMPORTANT NOTE ***
+ * This template uses obdev's shared VID/PID pair for Vendor Class devices
+ * with libusb: 0x16c0/0x5dc. Use this VID/PID pair ONLY if you understand
+ * the implications!
+ */
+#define USB_CFG_DEVICE_ID 0xdc, 0x05 /* = 0x05dc = 1500 */
+/* This is the ID of the product, low byte first. It is interpreted in the
+ * scope of the vendor ID. If you have registered your own VID with usb.org
+ * or if you have licensed a PID from somebody else, define it here. Otherwise
+ * you may use one of obdev's free shared VID/PID pairs. See the file
+ * USB-IDs-for-free.txt for details!
+ * *** IMPORTANT NOTE ***
+ * This template uses obdev's shared VID/PID pair for Vendor Class devices
+ * with libusb: 0x16c0/0x5dc. Use this VID/PID pair ONLY if you understand
+ * the implications!
+ */
+#define USB_CFG_DEVICE_VERSION 0x00, 0x01
+/* Version number of the device: Minor number first, then major number.
+ */
+#define USB_CFG_VENDOR_NAME 'o', 'b', 'd', 'e', 'v', '.', 'a', 't'
+#define USB_CFG_VENDOR_NAME_LEN 8
+/* These two values define the vendor name returned by the USB device. The name
+ * must be given as a list of characters under single quotes. The characters
+ * are interpreted as Unicode (UTF-16) entities.
+ * If you don't want a vendor name string, undefine these macros.
+ * ALWAYS define a vendor name containing your Internet domain name if you use
+ * obdev's free shared VID/PID pair. See the file USB-IDs-for-free.txt for
+ * details.
+ */
+#define USB_CFG_DEVICE_NAME 'T', 'e', 'm', 'p', 'l', 'a', 't', 'e'
+#define USB_CFG_DEVICE_NAME_LEN 8
+/* Same as above for the device name. If you don't want a device name, undefine
+ * the macros. See the file USB-IDs-for-free.txt before you assign a name if
+ * you use a shared VID/PID.
+ */
+/*#define USB_CFG_SERIAL_NUMBER 'N', 'o', 'n', 'e' */
+/*#define USB_CFG_SERIAL_NUMBER_LEN 0 */
+/* Same as above for the serial number. If you don't want a serial number,
+ * undefine the macros.
+ * It may be useful to provide the serial number through other means than at
+ * compile time. See the section about descriptor properties below for how
+ * to fine tune control over USB descriptors such as the string descriptor
+ * for the serial number.
+ */
+#define USB_CFG_DEVICE_CLASS 0xff /* set to 0 if deferred to interface */
+#define USB_CFG_DEVICE_SUBCLASS 0
+/* See USB specification if you want to conform to an existing device class.
+ * Class 0xff is "vendor specific".
+ */
+#define USB_CFG_INTERFACE_CLASS 0 /* define class here if not at device level */
+#define USB_CFG_INTERFACE_SUBCLASS 0
+#define USB_CFG_INTERFACE_PROTOCOL 0
+/* See USB specification if you want to conform to an existing device class or
+ * protocol. The following classes must be set at interface level:
+ * HID class is 3, no subclass and protocol required (but may be useful!)
+ * CDC class is 2, use subclass 2 and protocol 1 for ACM
+ */
+/* #define USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH 42 */
+/* Define this to the length of the HID report descriptor, if you implement
+ * an HID device. Otherwise don't define it or define it to 0.
+ * If you use this define, you must add a PROGMEM character array named
+ * "usbHidReportDescriptor" to your code which contains the report descriptor.
+ * Don't forget to keep the array and this define in sync!
+ */
+
+/* #define USB_PUBLIC static */
+/* Use the define above if you #include usbdrv.c instead of linking against it.
+ * This technique saves a couple of bytes in flash memory.
+ */
+
+/* ------------------- Fine Control over USB Descriptors ------------------- */
+/* If you don't want to use the driver's default USB descriptors, you can
+ * provide our own. These can be provided as (1) fixed length static data in
+ * flash memory, (2) fixed length static data in RAM or (3) dynamically at
+ * runtime in the function usbFunctionDescriptor(). See usbdrv.h for more
+ * information about this function.
+ * Descriptor handling is configured through the descriptor's properties. If
+ * no properties are defined or if they are 0, the default descriptor is used.
+ * Possible properties are:
+ * + USB_PROP_IS_DYNAMIC: The data for the descriptor should be fetched
+ * at runtime via usbFunctionDescriptor(). If the usbMsgPtr mechanism is
+ * used, the data is in FLASH by default. Add property USB_PROP_IS_RAM if
+ * you want RAM pointers.
+ * + USB_PROP_IS_RAM: The data returned by usbFunctionDescriptor() or found
+ * in static memory is in RAM, not in flash memory.
+ * + USB_PROP_LENGTH(len): If the data is in static memory (RAM or flash),
+ * the driver must know the descriptor's length. The descriptor itself is
+ * found at the address of a well known identifier (see below).
+ * List of static descriptor names (must be declared PROGMEM if in flash):
+ * char usbDescriptorDevice[];
+ * char usbDescriptorConfiguration[];
+ * char usbDescriptorHidReport[];
+ * char usbDescriptorString0[];
+ * int usbDescriptorStringVendor[];
+ * int usbDescriptorStringDevice[];
+ * int usbDescriptorStringSerialNumber[];
+ * Other descriptors can't be provided statically, they must be provided
+ * dynamically at runtime.
+ *
+ * Descriptor properties are or-ed or added together, e.g.:
+ * #define USB_CFG_DESCR_PROPS_DEVICE (USB_PROP_IS_RAM | USB_PROP_LENGTH(18))
+ *
+ * The following descriptors are defined:
+ * USB_CFG_DESCR_PROPS_DEVICE
+ * USB_CFG_DESCR_PROPS_CONFIGURATION
+ * USB_CFG_DESCR_PROPS_STRINGS
+ * USB_CFG_DESCR_PROPS_STRING_0
+ * USB_CFG_DESCR_PROPS_STRING_VENDOR
+ * USB_CFG_DESCR_PROPS_STRING_PRODUCT
+ * USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER
+ * USB_CFG_DESCR_PROPS_HID
+ * USB_CFG_DESCR_PROPS_HID_REPORT
+ * USB_CFG_DESCR_PROPS_UNKNOWN (for all descriptors not handled by the driver)
+ *
+ * Note about string descriptors: String descriptors are not just strings, they
+ * are Unicode strings prefixed with a 2 byte header. Example:
+ * int serialNumberDescriptor[] = {
+ * USB_STRING_DESCRIPTOR_HEADER(6),
+ * 'S', 'e', 'r', 'i', 'a', 'l'
+ * };
+ */
+
+#define USB_CFG_DESCR_PROPS_DEVICE 0
+#define USB_CFG_DESCR_PROPS_CONFIGURATION 0
+#define USB_CFG_DESCR_PROPS_STRINGS 0
+#define USB_CFG_DESCR_PROPS_STRING_0 0
+#define USB_CFG_DESCR_PROPS_STRING_VENDOR 0
+#define USB_CFG_DESCR_PROPS_STRING_PRODUCT 0
+#define USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER 0
+#define USB_CFG_DESCR_PROPS_HID 0
+#define USB_CFG_DESCR_PROPS_HID_REPORT 0
+#define USB_CFG_DESCR_PROPS_UNKNOWN 0
+
+
+//#define usbMsgPtr_t unsigned short
+/* If usbMsgPtr_t is not defined, it defaults to 'uchar *'. We may define it to
+ * a scalar type here because gcc generates slightly shorter code for scalar
+ * arithmetics than for pointer arithmetics. Remove this define for backward
+ * type compatibility or define it to an 8 bit type if you use data in RAM only
+ * and all RAM is below 256 bytes (tiny memory model in IAR CC).
+ */
+
+/* ----------------------- Optional MCU Description ------------------------ */
+
+/* The following configurations have working defaults in usbdrv.h. You
+ * usually don't need to set them explicitly. Only if you want to run
+ * the driver on a device which is not yet supported or with a compiler
+ * which is not fully supported (such as IAR C) or if you use a differnt
+ * interrupt than INT0, you may have to define some of these.
+ */
+/* #define USB_INTR_CFG MCUCR */
+/* #define USB_INTR_CFG_SET ((1 << ISC00) | (1 << ISC01)) */
+/* #define USB_INTR_CFG_CLR 0 */
+/* #define USB_INTR_ENABLE GIMSK */
+/* #define USB_INTR_ENABLE_BIT INT0 */
+/* #define USB_INTR_PENDING GIFR */
+/* #define USB_INTR_PENDING_BIT INTF0 */
+/* #define USB_INTR_VECTOR INT0_vect */
+
+#endif /* __usbconfig_h_included__ */
--- /dev/null
+/* Name: usbdrv.c
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2004-12-29
+ * Tabsize: 4
+ * Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+#include "usbdrv.h"
+#include "oddebug.h"
+
+/*
+General Description:
+This module implements the C-part of the USB driver. See usbdrv.h for a
+documentation of the entire driver.
+*/
+
+/* ------------------------------------------------------------------------- */
+
+/* raw USB registers / interface to assembler code: */
+uchar usbRxBuf[2*USB_BUFSIZE]; /* raw RX buffer: PID, 8 bytes data, 2 bytes CRC */
+uchar usbInputBufOffset; /* offset in usbRxBuf used for low level receiving */
+uchar usbDeviceAddr; /* assigned during enumeration, defaults to 0 */
+uchar usbNewDeviceAddr; /* device ID which should be set after status phase */
+uchar usbConfiguration; /* currently selected configuration. Administered by driver, but not used */
+volatile schar usbRxLen; /* = 0; number of bytes in usbRxBuf; 0 means free, -1 for flow control */
+uchar usbCurrentTok; /* last token received or endpoint number for last OUT token if != 0 */
+uchar usbRxToken; /* token for data we received; or endpont number for last OUT */
+volatile uchar usbTxLen = USBPID_NAK; /* number of bytes to transmit with next IN token or handshake token */
+uchar usbTxBuf[USB_BUFSIZE];/* data to transmit with next IN, free if usbTxLen contains handshake token */
+#if USB_COUNT_SOF
+volatile uchar usbSofCount; /* incremented by assembler module every SOF */
+#endif
+#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODE
+usbTxStatus_t usbTxStatus1;
+# if USB_CFG_HAVE_INTRIN_ENDPOINT3
+usbTxStatus_t usbTxStatus3;
+# endif
+#endif
+#if USB_CFG_CHECK_DATA_TOGGLING
+uchar usbCurrentDataToken;/* when we check data toggling to ignore duplicate packets */
+#endif
+
+/* USB status registers / not shared with asm code */
+usbMsgPtr_t usbMsgPtr; /* data to transmit next -- ROM or RAM address */
+static usbMsgLen_t usbMsgLen = USB_NO_MSG; /* remaining number of bytes */
+static uchar usbMsgFlags; /* flag values see below */
+
+#define USB_FLG_MSGPTR_IS_ROM (1<<6)
+#define USB_FLG_USE_USER_RW (1<<7)
+
+/*
+optimizing hints:
+- do not post/pre inc/dec integer values in operations
+- assign value of USB_READ_FLASH() to register variables and don't use side effects in arg
+- use narrow scope for variables which should be in X/Y/Z register
+- assign char sized expressions to variables to force 8 bit arithmetics
+*/
+
+/* -------------------------- String Descriptors --------------------------- */
+
+#if USB_CFG_DESCR_PROPS_STRINGS == 0
+
+#if USB_CFG_DESCR_PROPS_STRING_0 == 0
+#undef USB_CFG_DESCR_PROPS_STRING_0
+#define USB_CFG_DESCR_PROPS_STRING_0 sizeof(usbDescriptorString0)
+PROGMEM const char usbDescriptorString0[] = { /* language descriptor */
+ 4, /* sizeof(usbDescriptorString0): length of descriptor in bytes */
+ 3, /* descriptor type */
+ 0x09, 0x04, /* language index (0x0409 = US-English) */
+};
+#endif
+
+#if USB_CFG_DESCR_PROPS_STRING_VENDOR == 0 && USB_CFG_VENDOR_NAME_LEN
+#undef USB_CFG_DESCR_PROPS_STRING_VENDOR
+#define USB_CFG_DESCR_PROPS_STRING_VENDOR sizeof(usbDescriptorStringVendor)
+PROGMEM const int usbDescriptorStringVendor[] = {
+ USB_STRING_DESCRIPTOR_HEADER(USB_CFG_VENDOR_NAME_LEN),
+ USB_CFG_VENDOR_NAME
+};
+#endif
+
+#if USB_CFG_DESCR_PROPS_STRING_PRODUCT == 0 && USB_CFG_DEVICE_NAME_LEN
+#undef USB_CFG_DESCR_PROPS_STRING_PRODUCT
+#define USB_CFG_DESCR_PROPS_STRING_PRODUCT sizeof(usbDescriptorStringDevice)
+PROGMEM const int usbDescriptorStringDevice[] = {
+ USB_STRING_DESCRIPTOR_HEADER(USB_CFG_DEVICE_NAME_LEN),
+ USB_CFG_DEVICE_NAME
+};
+#endif
+
+#if USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER == 0 && USB_CFG_SERIAL_NUMBER_LEN
+#undef USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER
+#define USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER sizeof(usbDescriptorStringSerialNumber)
+PROGMEM const int usbDescriptorStringSerialNumber[] = {
+ USB_STRING_DESCRIPTOR_HEADER(USB_CFG_SERIAL_NUMBER_LEN),
+ USB_CFG_SERIAL_NUMBER
+};
+#endif
+
+#endif /* USB_CFG_DESCR_PROPS_STRINGS == 0 */
+
+/* --------------------------- Device Descriptor --------------------------- */
+
+#if USB_CFG_DESCR_PROPS_DEVICE == 0
+#undef USB_CFG_DESCR_PROPS_DEVICE
+#define USB_CFG_DESCR_PROPS_DEVICE sizeof(usbDescriptorDevice)
+PROGMEM const char usbDescriptorDevice[] = { /* USB device descriptor */
+ 18, /* sizeof(usbDescriptorDevice): length of descriptor in bytes */
+ USBDESCR_DEVICE, /* descriptor type */
+ 0x10, 0x01, /* USB version supported */
+ USB_CFG_DEVICE_CLASS,
+ USB_CFG_DEVICE_SUBCLASS,
+ 0, /* protocol */
+ 8, /* max packet size */
+ /* the following two casts affect the first byte of the constant only, but
+ * that's sufficient to avoid a warning with the default values.
+ */
+ (char)USB_CFG_VENDOR_ID,/* 2 bytes */
+ (char)USB_CFG_DEVICE_ID,/* 2 bytes */
+ USB_CFG_DEVICE_VERSION, /* 2 bytes */
+ USB_CFG_DESCR_PROPS_STRING_VENDOR != 0 ? 1 : 0, /* manufacturer string index */
+ USB_CFG_DESCR_PROPS_STRING_PRODUCT != 0 ? 2 : 0, /* product string index */
+ USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER != 0 ? 3 : 0, /* serial number string index */
+ 1, /* number of configurations */
+};
+#endif
+
+/* ----------------------- Configuration Descriptor ------------------------ */
+
+#if USB_CFG_DESCR_PROPS_HID_REPORT != 0 && USB_CFG_DESCR_PROPS_HID == 0
+#undef USB_CFG_DESCR_PROPS_HID
+#define USB_CFG_DESCR_PROPS_HID 9 /* length of HID descriptor in config descriptor below */
+#endif
+
+#if USB_CFG_DESCR_PROPS_CONFIGURATION == 0
+#undef USB_CFG_DESCR_PROPS_CONFIGURATION
+#define USB_CFG_DESCR_PROPS_CONFIGURATION sizeof(usbDescriptorConfiguration)
+PROGMEM const char usbDescriptorConfiguration[] = { /* USB configuration descriptor */
+ 9, /* sizeof(usbDescriptorConfiguration): length of descriptor in bytes */
+ USBDESCR_CONFIG, /* descriptor type */
+ 18 + 7 * USB_CFG_HAVE_INTRIN_ENDPOINT + 7 * USB_CFG_HAVE_INTRIN_ENDPOINT3 +
+ (USB_CFG_DESCR_PROPS_HID & 0xff), 0,
+ /* total length of data returned (including inlined descriptors) */
+ 1, /* number of interfaces in this configuration */
+ 1, /* index of this configuration */
+ 0, /* configuration name string index */
+#if USB_CFG_IS_SELF_POWERED
+ (1 << 7) | USBATTR_SELFPOWER, /* attributes */
+#else
+ (1 << 7) | USBATTR_REMOTEWAKE, /* attributes */
+#endif
+ USB_CFG_MAX_BUS_POWER/2, /* max USB current in 2mA units */
+/* interface descriptor follows inline: */
+ 9, /* sizeof(usbDescrInterface): length of descriptor in bytes */
+ USBDESCR_INTERFACE, /* descriptor type */
+ 0, /* index of this interface */
+ 0, /* alternate setting for this interface */
+ USB_CFG_HAVE_INTRIN_ENDPOINT + USB_CFG_HAVE_INTRIN_ENDPOINT3, /* endpoints excl 0: number of endpoint descriptors to follow */
+ USB_CFG_INTERFACE_CLASS,
+ USB_CFG_INTERFACE_SUBCLASS,
+ USB_CFG_INTERFACE_PROTOCOL,
+ 0, /* string index for interface */
+#if (USB_CFG_DESCR_PROPS_HID & 0xff) /* HID descriptor */
+ 9, /* sizeof(usbDescrHID): length of descriptor in bytes */
+ USBDESCR_HID, /* descriptor type: HID */
+ 0x01, 0x01, /* BCD representation of HID version */
+ 0x00, /* target country code */
+ 0x01, /* number of HID Report (or other HID class) Descriptor infos to follow */
+ 0x22, /* descriptor type: report */
+ USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH, 0, /* total length of report descriptor */
+#endif
+#if USB_CFG_HAVE_INTRIN_ENDPOINT /* endpoint descriptor for endpoint 1 */
+ 7, /* sizeof(usbDescrEndpoint) */
+ USBDESCR_ENDPOINT, /* descriptor type = endpoint */
+ (char)0x81, /* IN endpoint number 1 */
+ 0x03, /* attrib: Interrupt endpoint */
+ 8, 0, /* maximum packet size */
+ USB_CFG_INTR_POLL_INTERVAL, /* in ms */
+#endif
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3 /* endpoint descriptor for endpoint 3 */
+ 7, /* sizeof(usbDescrEndpoint) */
+ USBDESCR_ENDPOINT, /* descriptor type = endpoint */
+ (char)(0x80 | USB_CFG_EP3_NUMBER), /* IN endpoint number 3 */
+ 0x03, /* attrib: Interrupt endpoint */
+ 8, 0, /* maximum packet size */
+ USB_CFG_INTR_POLL_INTERVAL, /* in ms */
+#endif
+};
+#endif
+
+/* ------------------------------------------------------------------------- */
+
+static inline void usbResetDataToggling(void)
+{
+#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODE
+ USB_SET_DATATOKEN1(USB_INITIAL_DATATOKEN); /* reset data toggling for interrupt endpoint */
+# if USB_CFG_HAVE_INTRIN_ENDPOINT3
+ USB_SET_DATATOKEN3(USB_INITIAL_DATATOKEN); /* reset data toggling for interrupt endpoint */
+# endif
+#endif
+}
+
+static inline void usbResetStall(void)
+{
+#if USB_CFG_IMPLEMENT_HALT && USB_CFG_HAVE_INTRIN_ENDPOINT
+ usbTxLen1 = USBPID_NAK;
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+ usbTxLen3 = USBPID_NAK;
+#endif
+#endif
+}
+
+/* ------------------------------------------------------------------------- */
+
+#if !USB_CFG_SUPPRESS_INTR_CODE
+#if USB_CFG_HAVE_INTRIN_ENDPOINT
+static void usbGenericSetInterrupt(uchar *data, uchar len, usbTxStatus_t *txStatus)
+{
+uchar *p;
+schar i;
+
+#if USB_CFG_IMPLEMENT_HALT
+ if(usbTxLen1 == USBPID_STALL)
+ return;
+#endif
+ if(txStatus->len & 0x10){ /* packet buffer was empty */
+ txStatus->buffer[0] ^= USBPID_DATA0 ^ USBPID_DATA1; /* toggle token */
+ }else{
+ txStatus->len = USBPID_NAK; /* avoid sending outdated (overwritten) interrupt data */
+ }
+ p = txStatus->buffer + 1;
+ i = len;
+ do{ /* if len == 0, we still copy 1 byte, but that's no problem */
+ *p++ = *data++;
+ }while(--i > 0); /* loop control at the end is 2 bytes shorter than at beginning */
+ usbCrc16Append(&txStatus->buffer[1], len);
+ txStatus->len = len + 4; /* len must be given including sync byte */
+ DBG2(0x21 + (((int)txStatus >> 3) & 3), txStatus->buffer, len + 3);
+}
+
+USB_PUBLIC void usbSetInterrupt(uchar *data, uchar len)
+{
+ usbGenericSetInterrupt(data, len, &usbTxStatus1);
+}
+#endif
+
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+USB_PUBLIC void usbSetInterrupt3(uchar *data, uchar len)
+{
+ usbGenericSetInterrupt(data, len, &usbTxStatus3);
+}
+#endif
+#endif /* USB_CFG_SUPPRESS_INTR_CODE */
+
+/* ------------------ utilities for code following below ------------------- */
+
+/* Use defines for the switch statement so that we can choose between an
+ * if()else if() and a switch/case based implementation. switch() is more
+ * efficient for a LARGE set of sequential choices, if() is better in all other
+ * cases.
+ */
+#if USB_CFG_USE_SWITCH_STATEMENT
+# define SWITCH_START(cmd) switch(cmd){{
+# define SWITCH_CASE(value) }break; case (value):{
+# define SWITCH_CASE2(v1,v2) }break; case (v1): case(v2):{
+# define SWITCH_CASE3(v1,v2,v3) }break; case (v1): case(v2): case(v3):{
+# define SWITCH_DEFAULT }break; default:{
+# define SWITCH_END }}
+#else
+# define SWITCH_START(cmd) {uchar _cmd = cmd; if(0){
+# define SWITCH_CASE(value) }else if(_cmd == (value)){
+# define SWITCH_CASE2(v1,v2) }else if(_cmd == (v1) || _cmd == (v2)){
+# define SWITCH_CASE3(v1,v2,v3) }else if(_cmd == (v1) || _cmd == (v2) || (_cmd == v3)){
+# define SWITCH_DEFAULT }else{
+# define SWITCH_END }}
+#endif
+
+#ifndef USB_RX_USER_HOOK
+#define USB_RX_USER_HOOK(data, len)
+#endif
+#ifndef USB_SET_ADDRESS_HOOK
+#define USB_SET_ADDRESS_HOOK()
+#endif
+
+/* ------------------------------------------------------------------------- */
+
+/* We use if() instead of #if in the macro below because #if can't be used
+ * in macros and the compiler optimizes constant conditions anyway.
+ * This may cause problems with undefined symbols if compiled without
+ * optimizing!
+ */
+#define GET_DESCRIPTOR(cfgProp, staticName) \
+ if(cfgProp){ \
+ if((cfgProp) & USB_PROP_IS_RAM) \
+ flags = 0; \
+ if((cfgProp) & USB_PROP_IS_DYNAMIC){ \
+ len = usbFunctionDescriptor(rq); \
+ }else{ \
+ len = USB_PROP_LENGTH(cfgProp); \
+ usbMsgPtr = (usbMsgPtr_t)(staticName); \
+ } \
+ }
+
+/* usbDriverDescriptor() is similar to usbFunctionDescriptor(), but used
+ * internally for all types of descriptors.
+ */
+static inline usbMsgLen_t usbDriverDescriptor(usbRequest_t *rq)
+{
+usbMsgLen_t len = 0;
+uchar flags = USB_FLG_MSGPTR_IS_ROM;
+
+ SWITCH_START(rq->wValue.bytes[1])
+ SWITCH_CASE(USBDESCR_DEVICE) /* 1 */
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_DEVICE, usbDescriptorDevice)
+ SWITCH_CASE(USBDESCR_CONFIG) /* 2 */
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_CONFIGURATION, usbDescriptorConfiguration)
+ SWITCH_CASE(USBDESCR_STRING) /* 3 */
+#if USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC
+ if(USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_RAM)
+ flags = 0;
+ len = usbFunctionDescriptor(rq);
+#else /* USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC */
+ SWITCH_START(rq->wValue.bytes[0])
+ SWITCH_CASE(0)
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_0, usbDescriptorString0)
+ SWITCH_CASE(1)
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_VENDOR, usbDescriptorStringVendor)
+ SWITCH_CASE(2)
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_PRODUCT, usbDescriptorStringDevice)
+ SWITCH_CASE(3)
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER, usbDescriptorStringSerialNumber)
+ SWITCH_DEFAULT
+ if(USB_CFG_DESCR_PROPS_UNKNOWN & USB_PROP_IS_DYNAMIC){
+ len = usbFunctionDescriptor(rq);
+ }
+ SWITCH_END
+#endif /* USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC */
+#if USB_CFG_DESCR_PROPS_HID_REPORT /* only support HID descriptors if enabled */
+ SWITCH_CASE(USBDESCR_HID) /* 0x21 */
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_HID, usbDescriptorConfiguration + 18)
+ SWITCH_CASE(USBDESCR_HID_REPORT)/* 0x22 */
+ GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_HID_REPORT, usbDescriptorHidReport)
+#endif
+ SWITCH_DEFAULT
+ if(USB_CFG_DESCR_PROPS_UNKNOWN & USB_PROP_IS_DYNAMIC){
+ len = usbFunctionDescriptor(rq);
+ }
+ SWITCH_END
+ usbMsgFlags = flags;
+ return len;
+}
+
+/* ------------------------------------------------------------------------- */
+
+/* usbDriverSetup() is similar to usbFunctionSetup(), but it's used for
+ * standard requests instead of class and custom requests.
+ */
+static inline usbMsgLen_t usbDriverSetup(usbRequest_t *rq)
+{
+usbMsgLen_t len = 0;
+uchar *dataPtr = usbTxBuf + 9; /* there are 2 bytes free space at the end of the buffer */
+uchar value = rq->wValue.bytes[0];
+#if USB_CFG_IMPLEMENT_HALT
+uchar index = rq->wIndex.bytes[0];
+#endif
+
+ dataPtr[0] = 0; /* default reply common to USBRQ_GET_STATUS and USBRQ_GET_INTERFACE */
+ SWITCH_START(rq->bRequest)
+ SWITCH_CASE(USBRQ_GET_STATUS) /* 0 */
+ uchar recipient = rq->bmRequestType & USBRQ_RCPT_MASK; /* assign arith ops to variables to enforce byte size */
+ if(USB_CFG_IS_SELF_POWERED && recipient == USBRQ_RCPT_DEVICE)
+ dataPtr[0] = USB_CFG_IS_SELF_POWERED;
+#if USB_CFG_IMPLEMENT_HALT
+ if(recipient == USBRQ_RCPT_ENDPOINT && index == 0x81) /* request status for endpoint 1 */
+ dataPtr[0] = usbTxLen1 == USBPID_STALL;
+#endif
+ dataPtr[1] = 0;
+ len = 2;
+#if USB_CFG_IMPLEMENT_HALT
+ SWITCH_CASE2(USBRQ_CLEAR_FEATURE, USBRQ_SET_FEATURE) /* 1, 3 */
+ if(value == 0 && index == 0x81){ /* feature 0 == HALT for endpoint == 1 */
+ usbTxLen1 = rq->bRequest == USBRQ_CLEAR_FEATURE ? USBPID_NAK : USBPID_STALL;
+ usbResetDataToggling();
+ }
+#endif
+ SWITCH_CASE(USBRQ_SET_ADDRESS) /* 5 */
+ usbNewDeviceAddr = value;
+ USB_SET_ADDRESS_HOOK();
+ SWITCH_CASE(USBRQ_GET_DESCRIPTOR) /* 6 */
+ len = usbDriverDescriptor(rq);
+ goto skipMsgPtrAssignment;
+ SWITCH_CASE(USBRQ_GET_CONFIGURATION) /* 8 */
+ dataPtr = &usbConfiguration; /* send current configuration value */
+ len = 1;
+ SWITCH_CASE(USBRQ_SET_CONFIGURATION) /* 9 */
+ usbConfiguration = value;
+ usbResetStall();
+ SWITCH_CASE(USBRQ_GET_INTERFACE) /* 10 */
+ len = 1;
+#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODE
+ SWITCH_CASE(USBRQ_SET_INTERFACE) /* 11 */
+ usbResetDataToggling();
+ usbResetStall();
+#endif
+ SWITCH_DEFAULT /* 7=SET_DESCRIPTOR, 12=SYNC_FRAME */
+ /* Should we add an optional hook here? */
+ SWITCH_END
+ usbMsgPtr = (usbMsgPtr_t)dataPtr;
+skipMsgPtrAssignment:
+ return len;
+}
+
+/* ------------------------------------------------------------------------- */
+
+/* usbProcessRx() is called for every message received by the interrupt
+ * routine. It distinguishes between SETUP and DATA packets and processes
+ * them accordingly.
+ */
+static inline void usbProcessRx(uchar *data, uchar len)
+{
+usbRequest_t *rq = (void *)data;
+
+/* usbRxToken can be:
+ * 0x2d 00101101 (USBPID_SETUP for setup data)
+ * 0xe1 11100001 (USBPID_OUT: data phase of setup transfer)
+ * 0...0x0f for OUT on endpoint X
+ */
+ DBG2(0x10 + (usbRxToken & 0xf), data, len + 2); /* SETUP=1d, SETUP-DATA=11, OUTx=1x */
+ USB_RX_USER_HOOK(data, len)
+#if USB_CFG_IMPLEMENT_FN_WRITEOUT
+ if(usbRxToken < 0x10){ /* OUT to endpoint != 0: endpoint number in usbRxToken */
+ usbFunctionWriteOut(data, len);
+ return;
+ }
+#endif
+ if(usbRxToken == (uchar)USBPID_SETUP){
+ if(len != 8) /* Setup size must be always 8 bytes. Ignore otherwise. */
+ return;
+ usbMsgLen_t replyLen;
+ usbTxBuf[0] = USBPID_DATA0; /* initialize data toggling */
+ usbTxLen = USBPID_NAK; /* abort pending transmit */
+ usbMsgFlags = 0;
+ uchar type = rq->bmRequestType & USBRQ_TYPE_MASK;
+ if(type != USBRQ_TYPE_STANDARD){ /* standard requests are handled by driver */
+ replyLen = usbFunctionSetup(data);
+ }else{
+ replyLen = usbDriverSetup(rq);
+ }
+#if USB_CFG_IMPLEMENT_FN_READ || USB_CFG_IMPLEMENT_FN_WRITE
+ if(replyLen == USB_NO_MSG){ /* use user-supplied read/write function */
+ /* do some conditioning on replyLen, but on IN transfers only */
+ if((rq->bmRequestType & USBRQ_DIR_MASK) != USBRQ_DIR_HOST_TO_DEVICE){
+ if(sizeof(replyLen) < sizeof(rq->wLength.word)){ /* help compiler with optimizing */
+ replyLen = rq->wLength.bytes[0];
+ }else{
+ replyLen = rq->wLength.word;
+ }
+ }
+ usbMsgFlags = USB_FLG_USE_USER_RW;
+ }else /* The 'else' prevents that we limit a replyLen of USB_NO_MSG to the maximum transfer len. */
+#endif
+ if(sizeof(replyLen) < sizeof(rq->wLength.word)){ /* help compiler with optimizing */
+ if(!rq->wLength.bytes[1] && replyLen > rq->wLength.bytes[0]) /* limit length to max */
+ replyLen = rq->wLength.bytes[0];
+ }else{
+ if(replyLen > rq->wLength.word) /* limit length to max */
+ replyLen = rq->wLength.word;
+ }
+ usbMsgLen = replyLen;
+ }else{ /* usbRxToken must be USBPID_OUT, which means data phase of setup (control-out) */
+#if USB_CFG_IMPLEMENT_FN_WRITE
+ if(usbMsgFlags & USB_FLG_USE_USER_RW){
+ uchar rval = usbFunctionWrite(data, len);
+ if(rval == 0xff){ /* an error occurred */
+ usbTxLen = USBPID_STALL;
+ }else if(rval != 0){ /* This was the final package */
+ usbMsgLen = 0; /* answer with a zero-sized data packet */
+ }
+ }
+#endif
+ }
+}
+
+/* ------------------------------------------------------------------------- */
+
+/* This function is similar to usbFunctionRead(), but it's also called for
+ * data handled automatically by the driver (e.g. descriptor reads).
+ */
+static uchar usbDeviceRead(uchar *data, uchar len)
+{
+ if(len > 0){ /* don't bother app with 0 sized reads */
+#if USB_CFG_IMPLEMENT_FN_READ
+ if(usbMsgFlags & USB_FLG_USE_USER_RW){
+ len = usbFunctionRead(data, len);
+ }else
+#endif
+ {
+ uchar i = len;
+ usbMsgPtr_t r = usbMsgPtr;
+ if(usbMsgFlags & USB_FLG_MSGPTR_IS_ROM){ /* ROM data */
+ do{
+ uchar c = USB_READ_FLASH(r); /* assign to char size variable to enforce byte ops */
+ *data++ = c;
+ r++;
+ }while(--i);
+ }else{ /* RAM data */
+ do{
+ *data++ = *((uchar *)r);
+ r++;
+ }while(--i);
+ }
+ usbMsgPtr = r;
+ }
+ }
+ return len;
+}
+
+/* ------------------------------------------------------------------------- */
+
+/* usbBuildTxBlock() is called when we have data to transmit and the
+ * interrupt routine's transmit buffer is empty.
+ */
+static inline void usbBuildTxBlock(void)
+{
+usbMsgLen_t wantLen;
+uchar len;
+
+ wantLen = usbMsgLen;
+ if(wantLen > 8)
+ wantLen = 8;
+ usbMsgLen -= wantLen;
+ usbTxBuf[0] ^= USBPID_DATA0 ^ USBPID_DATA1; /* DATA toggling */
+ len = usbDeviceRead(usbTxBuf + 1, wantLen);
+ if(len <= 8){ /* valid data packet */
+ usbCrc16Append(&usbTxBuf[1], len);
+ len += 4; /* length including sync byte */
+ if(len < 12) /* a partial package identifies end of message */
+ usbMsgLen = USB_NO_MSG;
+ }else{
+ len = USBPID_STALL; /* stall the endpoint */
+ usbMsgLen = USB_NO_MSG;
+ }
+ usbTxLen = len;
+ DBG2(0x20, usbTxBuf, len-1);
+}
+
+/* ------------------------------------------------------------------------- */
+
+static inline void usbHandleResetHook(uchar notResetState)
+{
+#ifdef USB_RESET_HOOK
+static uchar wasReset;
+uchar isReset = !notResetState;
+
+ if(wasReset != isReset){
+ USB_RESET_HOOK(isReset);
+ wasReset = isReset;
+ }
+#else
+ notResetState = notResetState; // avoid compiler warning
+#endif
+}
+
+/* ------------------------------------------------------------------------- */
+
+USB_PUBLIC void usbPoll(void)
+{
+schar len;
+uchar i;
+
+ len = usbRxLen - 3;
+ if(len >= 0){
+/* We could check CRC16 here -- but ACK has already been sent anyway. If you
+ * need data integrity checks with this driver, check the CRC in your app
+ * code and report errors back to the host. Since the ACK was already sent,
+ * retries must be handled on application level.
+ * unsigned crc = usbCrc16(buffer + 1, usbRxLen - 3);
+ */
+ usbProcessRx(usbRxBuf + USB_BUFSIZE + 1 - usbInputBufOffset, len);
+#if USB_CFG_HAVE_FLOWCONTROL
+ if(usbRxLen > 0) /* only mark as available if not inactivated */
+ usbRxLen = 0;
+#else
+ usbRxLen = 0; /* mark rx buffer as available */
+#endif
+ }
+ if(usbTxLen & 0x10){ /* transmit system idle */
+ if(usbMsgLen != USB_NO_MSG){ /* transmit data pending? */
+ usbBuildTxBlock();
+ }
+ }
+ for(i = 20; i > 0; i--){
+ uchar usbLineStatus = USBIN & USBMASK;
+ if(usbLineStatus != 0) /* SE0 has ended */
+ goto isNotReset;
+ }
+ /* RESET condition, called multiple times during reset */
+ usbNewDeviceAddr = 0;
+ usbDeviceAddr = 0;
+ usbResetStall();
+ DBG1(0xff, 0, 0);
+isNotReset:
+ usbHandleResetHook(i);
+}
+
+/* ------------------------------------------------------------------------- */
+
+USB_PUBLIC void usbInit(void)
+{
+#if USB_INTR_CFG_SET != 0
+ USB_INTR_CFG |= USB_INTR_CFG_SET;
+#endif
+#if USB_INTR_CFG_CLR != 0
+ USB_INTR_CFG &= ~(USB_INTR_CFG_CLR);
+#endif
+ USB_INTR_ENABLE |= (1 << USB_INTR_ENABLE_BIT);
+ usbResetDataToggling();
+#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODE
+ usbTxLen1 = USBPID_NAK;
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+ usbTxLen3 = USBPID_NAK;
+#endif
+#endif
+}
+
+/* ------------------------------------------------------------------------- */
--- /dev/null
+/* Name: usbdrv.h
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2004-12-29
+ * Tabsize: 4
+ * Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+#ifndef __usbdrv_h_included__
+#define __usbdrv_h_included__
+
+/*
+Hardware Prerequisites:
+=======================
+USB lines D+ and D- MUST be wired to the same I/O port. We recommend that D+
+triggers the interrupt (best achieved by using INT0 for D+), but it is also
+possible to trigger the interrupt from D-. If D- is used, interrupts are also
+triggered by SOF packets. D- requires a pull-up of 1.5k to +3.5V (and the
+device must be powered at 3.5V) to identify as low-speed USB device. A
+pull-down or pull-up of 1M SHOULD be connected from D+ to +3.5V to prevent
+interference when no USB master is connected. If you use Zener diodes to limit
+the voltage on D+ and D-, you MUST use a pull-down resistor, not a pull-up.
+We use D+ as interrupt source and not D- because it does not trigger on
+keep-alive and RESET states. If you want to count keep-alive events with
+USB_COUNT_SOF, you MUST use D- as an interrupt source.
+
+As a compile time option, the 1.5k pull-up resistor on D- can be made
+switchable to allow the device to disconnect at will. See the definition of
+usbDeviceConnect() and usbDeviceDisconnect() further down in this file.
+
+Please adapt the values in usbconfig.h according to your hardware!
+
+The device MUST be clocked at exactly 12 MHz, 15 MHz, 16 MHz or 20 MHz
+or at 12.8 MHz resp. 16.5 MHz +/- 1%. See usbconfig-prototype.h for details.
+
+
+Limitations:
+============
+Robustness with respect to communication errors:
+The driver assumes error-free communication. It DOES check for errors in
+the PID, but does NOT check bit stuffing errors, SE0 in middle of a byte,
+token CRC (5 bit) and data CRC (16 bit). CRC checks can not be performed due
+to timing constraints: We must start sending a reply within 7 bit times.
+Bit stuffing and misplaced SE0 would have to be checked in real-time, but CPU
+performance does not permit that. The driver does not check Data0/Data1
+toggling, but application software can implement the check.
+
+Input characteristics:
+Since no differential receiver circuit is used, electrical interference
+robustness may suffer. The driver samples only one of the data lines with
+an ordinary I/O pin's input characteristics. However, since this is only a
+low speed USB implementation and the specification allows for 8 times the
+bit rate over the same hardware, we should be on the safe side. Even the spec
+requires detection of asymmetric states at high bit rate for SE0 detection.
+
+Number of endpoints:
+The driver supports the following endpoints:
+
+- Endpoint 0, the default control endpoint.
+- Any number of interrupt- or bulk-out endpoints. The data is sent to
+ usbFunctionWriteOut() and USB_CFG_IMPLEMENT_FN_WRITEOUT must be defined
+ to 1 to activate this feature. The endpoint number can be found in the
+ global variable 'usbRxToken'.
+- One default interrupt- or bulk-in endpoint. This endpoint is used for
+ interrupt- or bulk-in transfers which are not handled by any other endpoint.
+ You must define USB_CFG_HAVE_INTRIN_ENDPOINT in order to activate this
+ feature and call usbSetInterrupt() to send interrupt/bulk data.
+- One additional interrupt- or bulk-in endpoint. This was endpoint 3 in
+ previous versions of this driver but can now be configured to any endpoint
+ number. You must define USB_CFG_HAVE_INTRIN_ENDPOINT3 in order to activate
+ this feature and call usbSetInterrupt3() to send interrupt/bulk data. The
+ endpoint number can be set with USB_CFG_EP3_NUMBER.
+
+Please note that the USB standard forbids bulk endpoints for low speed devices!
+Most operating systems allow them anyway, but the AVR will spend 90% of the CPU
+time in the USB interrupt polling for bulk data.
+
+Maximum data payload:
+Data payload of control in and out transfers may be up to 254 bytes. In order
+to accept payload data of out transfers, you need to implement
+'usbFunctionWrite()'.
+
+USB Suspend Mode supply current:
+The USB standard limits power consumption to 500uA when the bus is in suspend
+mode. This is not a problem for self-powered devices since they don't need
+bus power anyway. Bus-powered devices can achieve this only by putting the
+CPU in sleep mode. The driver does not implement suspend handling by itself.
+However, the application may implement activity monitoring and wakeup from
+sleep. The host sends regular SE0 states on the bus to keep it active. These
+SE0 states can be detected by using D- as the interrupt source. Define
+USB_COUNT_SOF to 1 and use the global variable usbSofCount to check for bus
+activity.
+
+Operation without an USB master:
+The driver behaves neutral without connection to an USB master if D- reads
+as 1. To avoid spurious interrupts, we recommend a high impedance (e.g. 1M)
+pull-down or pull-up resistor on D+ (interrupt). If Zener diodes are used,
+use a pull-down. If D- becomes statically 0, the driver may block in the
+interrupt routine.
+
+Interrupt latency:
+The application must ensure that the USB interrupt is not disabled for more
+than 25 cycles (this is for 12 MHz, faster clocks allow longer latency).
+This implies that all interrupt routines must either have the "ISR_NOBLOCK"
+attribute set (see "avr/interrupt.h") or be written in assembler with "sei"
+as the first instruction.
+
+Maximum interrupt duration / CPU cycle consumption:
+The driver handles all USB communication during the interrupt service
+routine. The routine will not return before an entire USB message is received
+and the reply is sent. This may be up to ca. 1200 cycles @ 12 MHz (= 100us) if
+the host conforms to the standard. The driver will consume CPU cycles for all
+USB messages, even if they address another (low-speed) device on the same bus.
+
+*/
+
+
+#ifdef __cplusplus
+// This header should be included as C-header from C++ code. However if usbdrv.c
+// is incorporated into a C++ module with an include, function names are mangled
+// and this header must be parsed as C++ header, too. External modules should be
+// treated as C, though, because they are compiled separately as C code.
+extern "C" {
+#endif
+
+#include "usbconfig.h"
+#include "usbportability.h"
+
+#ifdef __cplusplus
+}
+#endif
+
+
+/* ------------------------------------------------------------------------- */
+/* --------------------------- Module Interface ---------------------------- */
+/* ------------------------------------------------------------------------- */
+
+#define USBDRV_VERSION 20121206
+/* This define uniquely identifies a driver version. It is a decimal number
+ * constructed from the driver's release date in the form YYYYMMDD. If the
+ * driver's behavior or interface changes, you can use this constant to
+ * distinguish versions. If it is not defined, the driver's release date is
+ * older than 2006-01-25.
+ */
+
+
+#ifndef USB_PUBLIC
+#define USB_PUBLIC
+#endif
+/* USB_PUBLIC is used as declaration attribute for all functions exported by
+ * the USB driver. The default is no attribute (see above). You may define it
+ * to static either in usbconfig.h or from the command line if you include
+ * usbdrv.c instead of linking against it. Including the C module of the driver
+ * directly in your code saves a couple of bytes in flash memory.
+ */
+
+#ifndef __ASSEMBLER__
+#ifndef uchar
+#define uchar unsigned char
+#endif
+#ifndef schar
+#define schar signed char
+#endif
+/* shortcuts for well defined 8 bit integer types */
+
+#if USB_CFG_LONG_TRANSFERS /* if more than 254 bytes transfer size required */
+# define usbMsgLen_t unsigned
+#else
+# define usbMsgLen_t uchar
+#endif
+/* usbMsgLen_t is the data type used for transfer lengths. By default, it is
+ * defined to uchar, allowing a maximum of 254 bytes (255 is reserved for
+ * USB_NO_MSG below). If the usbconfig.h defines USB_CFG_LONG_TRANSFERS to 1,
+ * a 16 bit data type is used, allowing up to 16384 bytes (the rest is used
+ * for flags in the descriptor configuration).
+ */
+#define USB_NO_MSG ((usbMsgLen_t)-1) /* constant meaning "no message" */
+
+#ifndef usbMsgPtr_t
+#define usbMsgPtr_t uchar *
+#endif
+/* Making usbMsgPtr_t a define allows the user of this library to define it to
+ * an 8 bit type on tiny devices. This reduces code size, especially if the
+ * compiler supports a tiny memory model.
+ * The type can be a pointer or scalar type, casts are made where necessary.
+ * Although it's paradoxical, Gcc 4 generates slightly better code for scalar
+ * types than for pointers.
+ */
+
+struct usbRequest; /* forward declaration */
+
+USB_PUBLIC void usbInit(void);
+/* This function must be called before interrupts are enabled and the main
+ * loop is entered. We exepct that the PORT and DDR bits for D+ and D- have
+ * not been changed from their default status (which is 0). If you have changed
+ * them, set both back to 0 (configure them as input with no internal pull-up).
+ */
+USB_PUBLIC void usbPoll(void);
+/* This function must be called at regular intervals from the main loop.
+ * Maximum delay between calls is somewhat less than 50ms (USB timeout for
+ * accepting a Setup message). Otherwise the device will not be recognized.
+ * Please note that debug outputs through the UART take ~ 0.5ms per byte
+ * at 19200 bps.
+ */
+extern usbMsgPtr_t usbMsgPtr;
+/* This variable may be used to pass transmit data to the driver from the
+ * implementation of usbFunctionWrite(). It is also used internally by the
+ * driver for standard control requests.
+ */
+USB_PUBLIC usbMsgLen_t usbFunctionSetup(uchar data[8]);
+/* This function is called when the driver receives a SETUP transaction from
+ * the host which is not answered by the driver itself (in practice: class and
+ * vendor requests). All control transfers start with a SETUP transaction where
+ * the host communicates the parameters of the following (optional) data
+ * transfer. The SETUP data is available in the 'data' parameter which can
+ * (and should) be casted to 'usbRequest_t *' for a more user-friendly access
+ * to parameters.
+ *
+ * If the SETUP indicates a control-in transfer, you should provide the
+ * requested data to the driver. There are two ways to transfer this data:
+ * (1) Set the global pointer 'usbMsgPtr' to the base of the static RAM data
+ * block and return the length of the data in 'usbFunctionSetup()'. The driver
+ * will handle the rest. Or (2) return USB_NO_MSG in 'usbFunctionSetup()'. The
+ * driver will then call 'usbFunctionRead()' when data is needed. See the
+ * documentation for usbFunctionRead() for details.
+ *
+ * If the SETUP indicates a control-out transfer, the only way to receive the
+ * data from the host is through the 'usbFunctionWrite()' call. If you
+ * implement this function, you must return USB_NO_MSG in 'usbFunctionSetup()'
+ * to indicate that 'usbFunctionWrite()' should be used. See the documentation
+ * of this function for more information. If you just want to ignore the data
+ * sent by the host, return 0 in 'usbFunctionSetup()'.
+ *
+ * Note that calls to the functions usbFunctionRead() and usbFunctionWrite()
+ * are only done if enabled by the configuration in usbconfig.h.
+ */
+USB_PUBLIC usbMsgLen_t usbFunctionDescriptor(struct usbRequest *rq);
+/* You need to implement this function ONLY if you provide USB descriptors at
+ * runtime (which is an expert feature). It is very similar to
+ * usbFunctionSetup() above, but it is called only to request USB descriptor
+ * data. See the documentation of usbFunctionSetup() above for more info.
+ */
+#if USB_CFG_HAVE_INTRIN_ENDPOINT
+USB_PUBLIC void usbSetInterrupt(uchar *data, uchar len);
+/* This function sets the message which will be sent during the next interrupt
+ * IN transfer. The message is copied to an internal buffer and must not exceed
+ * a length of 8 bytes. The message may be 0 bytes long just to indicate the
+ * interrupt status to the host.
+ * If you need to transfer more bytes, use a control read after the interrupt.
+ */
+#define usbInterruptIsReady() (usbTxLen1 & 0x10)
+/* This macro indicates whether the last interrupt message has already been
+ * sent. If you set a new interrupt message before the old was sent, the
+ * message already buffered will be lost.
+ */
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+USB_PUBLIC void usbSetInterrupt3(uchar *data, uchar len);
+#define usbInterruptIsReady3() (usbTxLen3 & 0x10)
+/* Same as above for endpoint 3 */
+#endif
+#endif /* USB_CFG_HAVE_INTRIN_ENDPOINT */
+#if USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH /* simplified interface for backward compatibility */
+#define usbHidReportDescriptor usbDescriptorHidReport
+/* should be declared as: PROGMEM char usbHidReportDescriptor[]; */
+/* If you implement an HID device, you need to provide a report descriptor.
+ * The HID report descriptor syntax is a bit complex. If you understand how
+ * report descriptors are constructed, we recommend that you use the HID
+ * Descriptor Tool from usb.org, see http://www.usb.org/developers/hidpage/.
+ * Otherwise you should probably start with a working example.
+ */
+#endif /* USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH */
+#if USB_CFG_IMPLEMENT_FN_WRITE
+USB_PUBLIC uchar usbFunctionWrite(uchar *data, uchar len);
+/* This function is called by the driver to provide a control transfer's
+ * payload data (control-out). It is called in chunks of up to 8 bytes. The
+ * total count provided in the current control transfer can be obtained from
+ * the 'length' property in the setup data. If an error occurred during
+ * processing, return 0xff (== -1). The driver will answer the entire transfer
+ * with a STALL token in this case. If you have received the entire payload
+ * successfully, return 1. If you expect more data, return 0. If you don't
+ * know whether the host will send more data (you should know, the total is
+ * provided in the usbFunctionSetup() call!), return 1.
+ * NOTE: If you return 0xff for STALL, 'usbFunctionWrite()' may still be called
+ * for the remaining data. You must continue to return 0xff for STALL in these
+ * calls.
+ * In order to get usbFunctionWrite() called, define USB_CFG_IMPLEMENT_FN_WRITE
+ * to 1 in usbconfig.h and return 0xff in usbFunctionSetup()..
+ */
+#endif /* USB_CFG_IMPLEMENT_FN_WRITE */
+#if USB_CFG_IMPLEMENT_FN_READ
+USB_PUBLIC uchar usbFunctionRead(uchar *data, uchar len);
+/* This function is called by the driver to ask the application for a control
+ * transfer's payload data (control-in). It is called in chunks of up to 8
+ * bytes each. You should copy the data to the location given by 'data' and
+ * return the actual number of bytes copied. If you return less than requested,
+ * the control-in transfer is terminated. If you return 0xff, the driver aborts
+ * the transfer with a STALL token.
+ * In order to get usbFunctionRead() called, define USB_CFG_IMPLEMENT_FN_READ
+ * to 1 in usbconfig.h and return 0xff in usbFunctionSetup()..
+ */
+#endif /* USB_CFG_IMPLEMENT_FN_READ */
+
+extern uchar usbRxToken; /* may be used in usbFunctionWriteOut() below */
+#if USB_CFG_IMPLEMENT_FN_WRITEOUT
+USB_PUBLIC void usbFunctionWriteOut(uchar *data, uchar len);
+/* This function is called by the driver when data is received on an interrupt-
+ * or bulk-out endpoint. The endpoint number can be found in the global
+ * variable usbRxToken. You must define USB_CFG_IMPLEMENT_FN_WRITEOUT to 1 in
+ * usbconfig.h to get this function called.
+ */
+#endif /* USB_CFG_IMPLEMENT_FN_WRITEOUT */
+#ifdef USB_CFG_PULLUP_IOPORTNAME
+#define usbDeviceConnect() ((USB_PULLUP_DDR |= (1<<USB_CFG_PULLUP_BIT)), \
+ (USB_PULLUP_OUT |= (1<<USB_CFG_PULLUP_BIT)))
+#define usbDeviceDisconnect() ((USB_PULLUP_DDR &= ~(1<<USB_CFG_PULLUP_BIT)), \
+ (USB_PULLUP_OUT &= ~(1<<USB_CFG_PULLUP_BIT)))
+#else /* USB_CFG_PULLUP_IOPORTNAME */
+#define usbDeviceConnect() (USBDDR &= ~(1<<USBMINUS))
+#define usbDeviceDisconnect() (USBDDR |= (1<<USBMINUS))
+#endif /* USB_CFG_PULLUP_IOPORTNAME */
+/* The macros usbDeviceConnect() and usbDeviceDisconnect() (intended to look
+ * like a function) connect resp. disconnect the device from the host's USB.
+ * If the constants USB_CFG_PULLUP_IOPORT and USB_CFG_PULLUP_BIT are defined
+ * in usbconfig.h, a disconnect consists of removing the pull-up resisitor
+ * from D-, otherwise the disconnect is done by brute-force pulling D- to GND.
+ * This does not conform to the spec, but it works.
+ * Please note that the USB interrupt must be disabled while the device is
+ * in disconnected state, or the interrupt handler will hang! You can either
+ * turn off the USB interrupt selectively with
+ * USB_INTR_ENABLE &= ~(1 << USB_INTR_ENABLE_BIT)
+ * or use cli() to disable interrupts globally.
+ */
+extern unsigned usbCrc16(unsigned data, uchar len);
+#define usbCrc16(data, len) usbCrc16((unsigned)(data), len)
+/* This function calculates the binary complement of the data CRC used in
+ * USB data packets. The value is used to build raw transmit packets.
+ * You may want to use this function for data checksums or to verify received
+ * data. We enforce 16 bit calling conventions for compatibility with IAR's
+ * tiny memory model.
+ */
+extern unsigned usbCrc16Append(unsigned data, uchar len);
+#define usbCrc16Append(data, len) usbCrc16Append((unsigned)(data), len)
+/* This function is equivalent to usbCrc16() above, except that it appends
+ * the 2 bytes CRC (lowbyte first) in the 'data' buffer after reading 'len'
+ * bytes.
+ */
+#if USB_CFG_HAVE_MEASURE_FRAME_LENGTH
+extern unsigned usbMeasureFrameLength(void);
+/* This function MUST be called IMMEDIATELY AFTER USB reset and measures 1/7 of
+ * the number of CPU cycles during one USB frame minus one low speed bit
+ * length. In other words: return value = 1499 * (F_CPU / 10.5 MHz)
+ * Since this is a busy wait, you MUST disable all interrupts with cli() before
+ * calling this function.
+ * This can be used to calibrate the AVR's RC oscillator.
+ */
+#endif
+extern uchar usbConfiguration;
+/* This value contains the current configuration set by the host. The driver
+ * allows setting and querying of this variable with the USB SET_CONFIGURATION
+ * and GET_CONFIGURATION requests, but does not use it otherwise.
+ * You may want to reflect the "configured" status with a LED on the device or
+ * switch on high power parts of the circuit only if the device is configured.
+ */
+#if USB_COUNT_SOF
+extern volatile uchar usbSofCount;
+/* This variable is incremented on every SOF packet. It is only available if
+ * the macro USB_COUNT_SOF is defined to a value != 0.
+ */
+#endif
+#if USB_CFG_CHECK_DATA_TOGGLING
+extern uchar usbCurrentDataToken;
+/* This variable can be checked in usbFunctionWrite() and usbFunctionWriteOut()
+ * to ignore duplicate packets.
+ */
+#endif
+
+#define USB_STRING_DESCRIPTOR_HEADER(stringLength) ((2*(stringLength)+2) | (3<<8))
+/* This macro builds a descriptor header for a string descriptor given the
+ * string's length. See usbdrv.c for an example how to use it.
+ */
+#if USB_CFG_HAVE_FLOWCONTROL
+extern volatile schar usbRxLen;
+#define usbDisableAllRequests() usbRxLen = -1
+/* Must be called from usbFunctionWrite(). This macro disables all data input
+ * from the USB interface. Requests from the host are answered with a NAK
+ * while they are disabled.
+ */
+#define usbEnableAllRequests() usbRxLen = 0
+/* May only be called if requests are disabled. This macro enables input from
+ * the USB interface after it has been disabled with usbDisableAllRequests().
+ */
+#define usbAllRequestsAreDisabled() (usbRxLen < 0)
+/* Use this macro to find out whether requests are disabled. It may be needed
+ * to ensure that usbEnableAllRequests() is never called when requests are
+ * enabled.
+ */
+#endif
+
+#define USB_SET_DATATOKEN1(token) usbTxBuf1[0] = token
+#define USB_SET_DATATOKEN3(token) usbTxBuf3[0] = token
+/* These two macros can be used by application software to reset data toggling
+ * for interrupt-in endpoints 1 and 3. Since the token is toggled BEFORE
+ * sending data, you must set the opposite value of the token which should come
+ * first.
+ */
+
+#endif /* __ASSEMBLER__ */
+
+
+/* ------------------------------------------------------------------------- */
+/* ----------------- Definitions for Descriptor Properties ----------------- */
+/* ------------------------------------------------------------------------- */
+/* This is advanced stuff. See usbconfig-prototype.h for more information
+ * about the various methods to define USB descriptors. If you do nothing,
+ * the default descriptors will be used.
+ */
+#define USB_PROP_IS_DYNAMIC (1u << 14)
+/* If this property is set for a descriptor, usbFunctionDescriptor() will be
+ * used to obtain the particular descriptor. Data directly returned via
+ * usbMsgPtr are FLASH data by default, combine (OR) with USB_PROP_IS_RAM to
+ * return RAM data.
+ */
+#define USB_PROP_IS_RAM (1u << 15)
+/* If this property is set for a descriptor, the data is read from RAM
+ * memory instead of Flash. The property is used for all methods to provide
+ * external descriptors.
+ */
+#define USB_PROP_LENGTH(len) ((len) & 0x3fff)
+/* If a static external descriptor is used, this is the total length of the
+ * descriptor in bytes.
+ */
+
+/* all descriptors which may have properties: */
+#ifndef USB_CFG_DESCR_PROPS_DEVICE
+#define USB_CFG_DESCR_PROPS_DEVICE 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_CONFIGURATION
+#define USB_CFG_DESCR_PROPS_CONFIGURATION 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_STRINGS
+#define USB_CFG_DESCR_PROPS_STRINGS 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_STRING_0
+#define USB_CFG_DESCR_PROPS_STRING_0 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_STRING_VENDOR
+#define USB_CFG_DESCR_PROPS_STRING_VENDOR 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_STRING_PRODUCT
+#define USB_CFG_DESCR_PROPS_STRING_PRODUCT 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER
+#define USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER 0
+#endif
+#ifndef USB_CFG_DESCR_PROPS_HID
+#define USB_CFG_DESCR_PROPS_HID 0
+#endif
+#if !(USB_CFG_DESCR_PROPS_HID_REPORT)
+# undef USB_CFG_DESCR_PROPS_HID_REPORT
+# if USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH /* do some backward compatibility tricks */
+# define USB_CFG_DESCR_PROPS_HID_REPORT USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH
+# else
+# define USB_CFG_DESCR_PROPS_HID_REPORT 0
+# endif
+#endif
+#ifndef USB_CFG_DESCR_PROPS_UNKNOWN
+#define USB_CFG_DESCR_PROPS_UNKNOWN 0
+#endif
+
+/* ------------------ forward declaration of descriptors ------------------- */
+/* If you use external static descriptors, they must be stored in global
+ * arrays as declared below:
+ */
+#ifndef __ASSEMBLER__
+extern
+#if !(USB_CFG_DESCR_PROPS_DEVICE & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+char usbDescriptorDevice[];
+
+extern
+#if !(USB_CFG_DESCR_PROPS_CONFIGURATION & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+char usbDescriptorConfiguration[];
+
+extern
+#if !(USB_CFG_DESCR_PROPS_HID_REPORT & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+char usbDescriptorHidReport[];
+
+extern
+#if !(USB_CFG_DESCR_PROPS_STRING_0 & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+char usbDescriptorString0[];
+
+extern
+#if !(USB_CFG_DESCR_PROPS_STRING_VENDOR & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+int usbDescriptorStringVendor[];
+
+extern
+#if !(USB_CFG_DESCR_PROPS_STRING_PRODUCT & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+int usbDescriptorStringDevice[];
+
+extern
+#if !(USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER & USB_PROP_IS_RAM)
+PROGMEM const
+#endif
+int usbDescriptorStringSerialNumber[];
+
+#endif /* __ASSEMBLER__ */
+
+/* ------------------------------------------------------------------------- */
+/* ------------------------ General Purpose Macros ------------------------- */
+/* ------------------------------------------------------------------------- */
+
+#define USB_CONCAT(a, b) a ## b
+#define USB_CONCAT_EXPANDED(a, b) USB_CONCAT(a, b)
+
+#define USB_OUTPORT(name) USB_CONCAT(PORT, name)
+#define USB_INPORT(name) USB_CONCAT(PIN, name)
+#define USB_DDRPORT(name) USB_CONCAT(DDR, name)
+/* The double-define trick above lets us concatenate strings which are
+ * defined by macros.
+ */
+
+/* ------------------------------------------------------------------------- */
+/* ------------------------- Constant definitions -------------------------- */
+/* ------------------------------------------------------------------------- */
+
+#if !defined __ASSEMBLER__ && (!defined USB_CFG_VENDOR_ID || !defined USB_CFG_DEVICE_ID)
+#warning "You should define USB_CFG_VENDOR_ID and USB_CFG_DEVICE_ID in usbconfig.h"
+/* If the user has not defined IDs, we default to obdev's free IDs.
+ * See USB-IDs-for-free.txt for details.
+ */
+#endif
+
+/* make sure we have a VID and PID defined, byte order is lowbyte, highbyte */
+#ifndef USB_CFG_VENDOR_ID
+# define USB_CFG_VENDOR_ID 0xc0, 0x16 /* = 0x16c0 = 5824 = voti.nl */
+#endif
+
+#ifndef USB_CFG_DEVICE_ID
+# if USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH
+# define USB_CFG_DEVICE_ID 0xdf, 0x05 /* = 0x5df = 1503, shared PID for HIDs */
+# elif USB_CFG_INTERFACE_CLASS == 2
+# define USB_CFG_DEVICE_ID 0xe1, 0x05 /* = 0x5e1 = 1505, shared PID for CDC Modems */
+# else
+# define USB_CFG_DEVICE_ID 0xdc, 0x05 /* = 0x5dc = 1500, obdev's free PID */
+# endif
+#endif
+
+/* Derive Output, Input and DataDirection ports from port names */
+#ifndef USB_CFG_IOPORTNAME
+#error "You must define USB_CFG_IOPORTNAME in usbconfig.h, see usbconfig-prototype.h"
+#endif
+
+#define USBOUT USB_OUTPORT(USB_CFG_IOPORTNAME)
+#define USB_PULLUP_OUT USB_OUTPORT(USB_CFG_PULLUP_IOPORTNAME)
+#define USBIN USB_INPORT(USB_CFG_IOPORTNAME)
+#define USBDDR USB_DDRPORT(USB_CFG_IOPORTNAME)
+#define USB_PULLUP_DDR USB_DDRPORT(USB_CFG_PULLUP_IOPORTNAME)
+
+#define USBMINUS USB_CFG_DMINUS_BIT
+#define USBPLUS USB_CFG_DPLUS_BIT
+#define USBIDLE (1<<USB_CFG_DMINUS_BIT) /* value representing J state */
+#define USBMASK ((1<<USB_CFG_DPLUS_BIT) | (1<<USB_CFG_DMINUS_BIT)) /* mask for USB I/O bits */
+
+/* defines for backward compatibility with older driver versions: */
+#define USB_CFG_IOPORT USB_OUTPORT(USB_CFG_IOPORTNAME)
+#ifdef USB_CFG_PULLUP_IOPORTNAME
+#define USB_CFG_PULLUP_IOPORT USB_OUTPORT(USB_CFG_PULLUP_IOPORTNAME)
+#endif
+
+#ifndef USB_CFG_EP3_NUMBER /* if not defined in usbconfig.h */
+#define USB_CFG_EP3_NUMBER 3
+#endif
+
+#ifndef USB_CFG_HAVE_INTRIN_ENDPOINT3
+#define USB_CFG_HAVE_INTRIN_ENDPOINT3 0
+#endif
+
+#define USB_BUFSIZE 11 /* PID, 8 bytes data, 2 bytes CRC */
+
+/* ----- Try to find registers and bits responsible for ext interrupt 0 ----- */
+
+#ifndef USB_INTR_CFG /* allow user to override our default */
+# if defined EICRA
+# define USB_INTR_CFG EICRA
+# else
+# define USB_INTR_CFG MCUCR
+# endif
+#endif
+#ifndef USB_INTR_CFG_SET /* allow user to override our default */
+# if defined(USB_COUNT_SOF) || defined(USB_SOF_HOOK)
+# define USB_INTR_CFG_SET (1 << ISC01) /* cfg for falling edge */
+ /* If any SOF logic is used, the interrupt must be wired to D- where
+ * we better trigger on falling edge
+ */
+# else
+# define USB_INTR_CFG_SET ((1 << ISC00) | (1 << ISC01)) /* cfg for rising edge */
+# endif
+#endif
+#ifndef USB_INTR_CFG_CLR /* allow user to override our default */
+# define USB_INTR_CFG_CLR 0 /* no bits to clear */
+#endif
+
+#ifndef USB_INTR_ENABLE /* allow user to override our default */
+# if defined GIMSK
+# define USB_INTR_ENABLE GIMSK
+# elif defined EIMSK
+# define USB_INTR_ENABLE EIMSK
+# else
+# define USB_INTR_ENABLE GICR
+# endif
+#endif
+#ifndef USB_INTR_ENABLE_BIT /* allow user to override our default */
+# define USB_INTR_ENABLE_BIT INT0
+#endif
+
+#ifndef USB_INTR_PENDING /* allow user to override our default */
+# if defined EIFR
+# define USB_INTR_PENDING EIFR
+# else
+# define USB_INTR_PENDING GIFR
+# endif
+#endif
+#ifndef USB_INTR_PENDING_BIT /* allow user to override our default */
+# define USB_INTR_PENDING_BIT INTF0
+#endif
+
+/*
+The defines above don't work for the following chips
+at90c8534: no ISC0?, no PORTB, can't find a data sheet
+at86rf401: no PORTB, no MCUCR etc, low clock rate
+atmega103: no ISC0? (maybe omission in header, can't find data sheet)
+atmega603: not defined in avr-libc
+at43usb320, at43usb355, at76c711: have USB anyway
+at94k: is different...
+
+at90s1200, attiny11, attiny12, attiny15, attiny28: these have no RAM
+*/
+
+/* ------------------------------------------------------------------------- */
+/* ----------------- USB Specification Constants and Types ----------------- */
+/* ------------------------------------------------------------------------- */
+
+/* USB Token values */
+#define USBPID_SETUP 0x2d
+#define USBPID_OUT 0xe1
+#define USBPID_IN 0x69
+#define USBPID_DATA0 0xc3
+#define USBPID_DATA1 0x4b
+
+#define USBPID_ACK 0xd2
+#define USBPID_NAK 0x5a
+#define USBPID_STALL 0x1e
+
+#ifndef USB_INITIAL_DATATOKEN
+#define USB_INITIAL_DATATOKEN USBPID_DATA1
+#endif
+
+#ifndef __ASSEMBLER__
+
+typedef struct usbTxStatus{
+ volatile uchar len;
+ uchar buffer[USB_BUFSIZE];
+}usbTxStatus_t;
+
+extern usbTxStatus_t usbTxStatus1, usbTxStatus3;
+#define usbTxLen1 usbTxStatus1.len
+#define usbTxBuf1 usbTxStatus1.buffer
+#define usbTxLen3 usbTxStatus3.len
+#define usbTxBuf3 usbTxStatus3.buffer
+
+
+typedef union usbWord{
+ unsigned word;
+ uchar bytes[2];
+}usbWord_t;
+
+typedef struct usbRequest{
+ uchar bmRequestType;
+ uchar bRequest;
+ usbWord_t wValue;
+ usbWord_t wIndex;
+ usbWord_t wLength;
+}usbRequest_t;
+/* This structure matches the 8 byte setup request */
+#endif
+
+/* bmRequestType field in USB setup:
+ * d t t r r r r r, where
+ * d ..... direction: 0=host->device, 1=device->host
+ * t ..... type: 0=standard, 1=class, 2=vendor, 3=reserved
+ * r ..... recipient: 0=device, 1=interface, 2=endpoint, 3=other
+ */
+
+/* USB setup recipient values */
+#define USBRQ_RCPT_MASK 0x1f
+#define USBRQ_RCPT_DEVICE 0
+#define USBRQ_RCPT_INTERFACE 1
+#define USBRQ_RCPT_ENDPOINT 2
+
+/* USB request type values */
+#define USBRQ_TYPE_MASK 0x60
+#define USBRQ_TYPE_STANDARD (0<<5)
+#define USBRQ_TYPE_CLASS (1<<5)
+#define USBRQ_TYPE_VENDOR (2<<5)
+
+/* USB direction values: */
+#define USBRQ_DIR_MASK 0x80
+#define USBRQ_DIR_HOST_TO_DEVICE (0<<7)
+#define USBRQ_DIR_DEVICE_TO_HOST (1<<7)
+
+/* USB Standard Requests */
+#define USBRQ_GET_STATUS 0
+#define USBRQ_CLEAR_FEATURE 1
+#define USBRQ_SET_FEATURE 3
+#define USBRQ_SET_ADDRESS 5
+#define USBRQ_GET_DESCRIPTOR 6
+#define USBRQ_SET_DESCRIPTOR 7
+#define USBRQ_GET_CONFIGURATION 8
+#define USBRQ_SET_CONFIGURATION 9
+#define USBRQ_GET_INTERFACE 10
+#define USBRQ_SET_INTERFACE 11
+#define USBRQ_SYNCH_FRAME 12
+
+/* USB descriptor constants */
+#define USBDESCR_DEVICE 1
+#define USBDESCR_CONFIG 2
+#define USBDESCR_STRING 3
+#define USBDESCR_INTERFACE 4
+#define USBDESCR_ENDPOINT 5
+#define USBDESCR_HID 0x21
+#define USBDESCR_HID_REPORT 0x22
+#define USBDESCR_HID_PHYS 0x23
+
+//#define USBATTR_BUSPOWER 0x80 // USB 1.1 does not define this value any more
+#define USBATTR_BUSPOWER 0
+#define USBATTR_SELFPOWER 0x40
+#define USBATTR_REMOTEWAKE 0x20
+
+/* USB HID Requests */
+#define USBRQ_HID_GET_REPORT 0x01
+#define USBRQ_HID_GET_IDLE 0x02
+#define USBRQ_HID_GET_PROTOCOL 0x03
+#define USBRQ_HID_SET_REPORT 0x09
+#define USBRQ_HID_SET_IDLE 0x0a
+#define USBRQ_HID_SET_PROTOCOL 0x0b
+
+/* ------------------------------------------------------------------------- */
+
+#endif /* __usbdrv_h_included__ */
--- /dev/null
+/* Name: usbdrvasm.S
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2007-06-13
+ * Tabsize: 4
+ * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/*
+General Description:
+This module is the assembler part of the USB driver. This file contains
+general code (preprocessor acrobatics and CRC computation) and then includes
+the file appropriate for the given clock rate.
+*/
+
+#define __SFR_OFFSET 0 /* used by avr-libc's register definitions */
+#include "usbportability.h"
+#include "usbdrv.h" /* for common defs */
+
+/* register names */
+#define x1 r16
+#define x2 r17
+#define shift r18
+#define cnt r19
+#define x3 r20
+#define x4 r21
+#define x5 r22
+#define bitcnt x5
+#define phase x4
+#define leap x4
+
+/* Some assembler dependent definitions and declarations: */
+
+#ifdef __IAR_SYSTEMS_ASM__
+ extern usbRxBuf, usbDeviceAddr, usbNewDeviceAddr, usbInputBufOffset
+ extern usbCurrentTok, usbRxLen, usbRxToken, usbTxLen
+ extern usbTxBuf, usbTxStatus1, usbTxStatus3
+# if USB_COUNT_SOF
+ extern usbSofCount
+# endif
+ public usbCrc16
+ public usbCrc16Append
+
+ COMMON INTVEC
+# ifndef USB_INTR_VECTOR
+ ORG INT0_vect
+# else /* USB_INTR_VECTOR */
+ ORG USB_INTR_VECTOR
+# undef USB_INTR_VECTOR
+# endif /* USB_INTR_VECTOR */
+# define USB_INTR_VECTOR usbInterruptHandler
+ rjmp USB_INTR_VECTOR
+ RSEG CODE
+
+#else /* __IAR_SYSTEMS_ASM__ */
+
+# ifndef USB_INTR_VECTOR /* default to hardware interrupt INT0 */
+# ifdef INT0_vect
+# define USB_INTR_VECTOR INT0_vect // this is the "new" define for the vector
+# else
+# define USB_INTR_VECTOR SIG_INTERRUPT0 // this is the "old" vector
+# endif
+# endif
+ .text
+ .global USB_INTR_VECTOR
+ .type USB_INTR_VECTOR, @function
+ .global usbCrc16
+ .global usbCrc16Append
+#endif /* __IAR_SYSTEMS_ASM__ */
+
+
+#if USB_INTR_PENDING < 0x40 /* This is an I/O address, use in and out */
+# define USB_LOAD_PENDING(reg) in reg, USB_INTR_PENDING
+# define USB_STORE_PENDING(reg) out USB_INTR_PENDING, reg
+#else /* It's a memory address, use lds and sts */
+# define USB_LOAD_PENDING(reg) lds reg, USB_INTR_PENDING
+# define USB_STORE_PENDING(reg) sts USB_INTR_PENDING, reg
+#endif
+
+#define usbTxLen1 usbTxStatus1
+#define usbTxBuf1 (usbTxStatus1 + 1)
+#define usbTxLen3 usbTxStatus3
+#define usbTxBuf3 (usbTxStatus3 + 1)
+
+
+;----------------------------------------------------------------------------
+; Utility functions
+;----------------------------------------------------------------------------
+
+#ifdef __IAR_SYSTEMS_ASM__
+/* Register assignments for usbCrc16 on IAR cc */
+/* Calling conventions on IAR:
+ * First parameter passed in r16/r17, second in r18/r19 and so on.
+ * Callee must preserve r4-r15, r24-r29 (r28/r29 is frame pointer)
+ * Result is passed in r16/r17
+ * In case of the "tiny" memory model, pointers are only 8 bit with no
+ * padding. We therefore pass argument 1 as "16 bit unsigned".
+ */
+RTMODEL "__rt_version", "3"
+/* The line above will generate an error if cc calling conventions change.
+ * The value "3" above is valid for IAR 4.10B/W32
+ */
+# define argLen r18 /* argument 2 */
+# define argPtrL r16 /* argument 1 */
+# define argPtrH r17 /* argument 1 */
+
+# define resCrcL r16 /* result */
+# define resCrcH r17 /* result */
+
+# define ptrL ZL
+# define ptrH ZH
+# define ptr Z
+# define byte r22
+# define bitCnt r19
+# define polyL r20
+# define polyH r21
+# define scratch r23
+
+#else /* __IAR_SYSTEMS_ASM__ */
+/* Register assignments for usbCrc16 on gcc */
+/* Calling conventions on gcc:
+ * First parameter passed in r24/r25, second in r22/23 and so on.
+ * Callee must preserve r1-r17, r28/r29
+ * Result is passed in r24/r25
+ */
+# define argLen r22 /* argument 2 */
+# define argPtrL r24 /* argument 1 */
+# define argPtrH r25 /* argument 1 */
+
+# define resCrcL r24 /* result */
+# define resCrcH r25 /* result */
+
+# define ptrL XL
+# define ptrH XH
+# define ptr x
+# define byte r18
+# define bitCnt r19
+# define polyL r20
+# define polyH r21
+# define scratch r23
+
+#endif
+
+#if USB_USE_FAST_CRC
+
+; This implementation is faster, but has bigger code size
+; Thanks to Slawomir Fras (BoskiDialer) for this code and to Shay Green for
+; even further optimizations!
+; It implements the following C pseudo-code:
+; unsigned table(unsigned char x)
+; {
+; unsigned value;
+;
+; value = (unsigned)x << 6;
+; value ^= (unsigned)x << 7;
+; if(parity(x))
+; value ^= 0xc001;
+; return value;
+; }
+; unsigned usbCrc16(unsigned char *argPtr, unsigned char argLen)
+; {
+; unsigned crc = 0xffff;
+;
+; while(argLen--)
+; crc = table(lo8(crc) ^ *argPtr++) ^ hi8(crc);
+; return ~crc;
+; }
+
+; extern unsigned usbCrc16(unsigned char *argPtr, unsigned char argLen);
+; argPtr r24+25 / r16+r17
+; argLen r22 / r18
+; temp variables:
+; byte r18 / r22
+; scratch r23
+; resCrc r24+r25 / r16+r17
+; ptr X / Z
+usbCrc16:
+ movw ptrL, argPtrL
+ ldi resCrcL, 0xFF
+ ldi resCrcH, 0xFF
+ clr bitCnt ; zero reg
+ rjmp usbCrc16LoopTest
+usbCrc16ByteLoop:
+ ld byte, ptr+
+ eor byte, resCrcL ; scratch is now 'x' in table()
+ mov scratch, byte ; compute parity of 'x'
+ swap byte
+ eor byte, scratch
+ mov resCrcL, byte
+ lsr byte
+ lsr byte
+ eor byte, resCrcL
+ inc byte
+ andi byte, 2 ; byte is now parity(x) << 1
+ cp bitCnt, byte ; c = (byte != 0), then put in high bit
+ ror scratch ; so that after xoring, shifting, and xoring, it gives
+ ror byte ; the desired 0xC0 with resCrcH
+ mov resCrcL, byte
+ eor resCrcL, resCrcH
+ mov resCrcH, scratch
+ lsr scratch
+ ror byte
+ eor resCrcH, scratch
+ eor resCrcL, byte
+usbCrc16LoopTest:
+ subi argLen, 1
+ brsh usbCrc16ByteLoop
+ com resCrcL
+ com resCrcH
+ ret
+
+#else /* USB_USE_FAST_CRC */
+
+; This implementation is slower, but has less code size
+;
+; extern unsigned usbCrc16(unsigned char *argPtr, unsigned char argLen);
+; argPtr r24+25 / r16+r17
+; argLen r22 / r18
+; temp variables:
+; byte r18 / r22
+; bitCnt r19
+; poly r20+r21
+; scratch r23
+; resCrc r24+r25 / r16+r17
+; ptr X / Z
+usbCrc16:
+ mov ptrL, argPtrL
+ mov ptrH, argPtrH
+ ldi resCrcL, 0
+ ldi resCrcH, 0
+ ldi polyL, lo8(0xa001)
+ ldi polyH, hi8(0xa001)
+ com argLen ; argLen = -argLen - 1: modified loop to ensure that carry is set
+ ldi bitCnt, 0 ; loop counter with starnd condition = end condition
+ rjmp usbCrcLoopEntry
+usbCrcByteLoop:
+ ld byte, ptr+
+ eor resCrcL, byte
+usbCrcBitLoop:
+ ror resCrcH ; carry is always set here (see brcs jumps to here)
+ ror resCrcL
+ brcs usbCrcNoXor
+ eor resCrcL, polyL
+ eor resCrcH, polyH
+usbCrcNoXor:
+ subi bitCnt, 224 ; (8 * 224) % 256 = 0; this loop iterates 8 times
+ brcs usbCrcBitLoop
+usbCrcLoopEntry:
+ subi argLen, -1
+ brcs usbCrcByteLoop
+usbCrcReady:
+ ret
+; Thanks to Reimar Doeffinger for optimizing this CRC routine!
+
+#endif /* USB_USE_FAST_CRC */
+
+; extern unsigned usbCrc16Append(unsigned char *data, unsigned char len);
+usbCrc16Append:
+ rcall usbCrc16
+ st ptr+, resCrcL
+ st ptr+, resCrcH
+ ret
+
+#undef argLen
+#undef argPtrL
+#undef argPtrH
+#undef resCrcL
+#undef resCrcH
+#undef ptrL
+#undef ptrH
+#undef ptr
+#undef byte
+#undef bitCnt
+#undef polyL
+#undef polyH
+#undef scratch
+
+
+#if USB_CFG_HAVE_MEASURE_FRAME_LENGTH
+#ifdef __IAR_SYSTEMS_ASM__
+/* Register assignments for usbMeasureFrameLength on IAR cc */
+/* Calling conventions on IAR:
+ * First parameter passed in r16/r17, second in r18/r19 and so on.
+ * Callee must preserve r4-r15, r24-r29 (r28/r29 is frame pointer)
+ * Result is passed in r16/r17
+ * In case of the "tiny" memory model, pointers are only 8 bit with no
+ * padding. We therefore pass argument 1 as "16 bit unsigned".
+ */
+# define resL r16
+# define resH r17
+# define cnt16L r30
+# define cnt16H r31
+# define cntH r18
+
+#else /* __IAR_SYSTEMS_ASM__ */
+/* Register assignments for usbMeasureFrameLength on gcc */
+/* Calling conventions on gcc:
+ * First parameter passed in r24/r25, second in r22/23 and so on.
+ * Callee must preserve r1-r17, r28/r29
+ * Result is passed in r24/r25
+ */
+# define resL r24
+# define resH r25
+# define cnt16L r24
+# define cnt16H r25
+# define cntH r26
+#endif
+# define cnt16 cnt16L
+
+; extern unsigned usbMeasurePacketLength(void);
+; returns time between two idle strobes in multiples of 7 CPU clocks
+.global usbMeasureFrameLength
+usbMeasureFrameLength:
+ ldi cntH, 6 ; wait ~ 10 ms for D- == 0
+ clr cnt16L
+ clr cnt16H
+usbMFTime16:
+ dec cntH
+ breq usbMFTimeout
+usbMFWaitStrobe: ; first wait for D- == 0 (idle strobe)
+ sbiw cnt16, 1 ;[0] [6]
+ breq usbMFTime16 ;[2]
+ sbic USBIN, USBMINUS ;[3]
+ rjmp usbMFWaitStrobe ;[4]
+usbMFWaitIdle: ; then wait until idle again
+ sbis USBIN, USBMINUS ;1 wait for D- == 1
+ rjmp usbMFWaitIdle ;2
+ ldi cnt16L, 1 ;1 represents cycles so far
+ clr cnt16H ;1
+usbMFWaitLoop:
+ in cntH, USBIN ;[0] [7]
+ adiw cnt16, 1 ;[1]
+ breq usbMFTimeout ;[3]
+ andi cntH, USBMASK ;[4]
+ brne usbMFWaitLoop ;[5]
+usbMFTimeout:
+#if resL != cnt16L
+ mov resL, cnt16L
+ mov resH, cnt16H
+#endif
+ ret
+
+#undef resL
+#undef resH
+#undef cnt16
+#undef cnt16L
+#undef cnt16H
+#undef cntH
+
+#endif /* USB_CFG_HAVE_MEASURE_FRAME_LENGTH */
+
+;----------------------------------------------------------------------------
+; Now include the clock rate specific code
+;----------------------------------------------------------------------------
+
+#ifndef USB_CFG_CLOCK_KHZ
+# ifdef F_CPU
+# define USB_CFG_CLOCK_KHZ (F_CPU/1000)
+# else
+# error "USB_CFG_CLOCK_KHZ not defined in usbconfig.h and no F_CPU set!"
+# endif
+#endif
+
+#if USB_CFG_CHECK_CRC /* separate dispatcher for CRC type modules */
+# if USB_CFG_CLOCK_KHZ == 18000
+# include "usbdrvasm18-crc.inc"
+# else
+# error "USB_CFG_CLOCK_KHZ is not one of the supported rates for USB_CFG_CHECK_CRC!"
+# endif
+#else /* USB_CFG_CHECK_CRC */
+# if USB_CFG_CLOCK_KHZ == 12000
+# include "usbdrvasm12.inc"
+# elif USB_CFG_CLOCK_KHZ == 12800
+# include "usbdrvasm128.inc"
+# elif USB_CFG_CLOCK_KHZ == 15000
+# include "usbdrvasm15.inc"
+# elif USB_CFG_CLOCK_KHZ == 16000
+# include "usbdrvasm16.inc"
+# elif USB_CFG_CLOCK_KHZ == 16500
+# include "usbdrvasm165.inc"
+# elif USB_CFG_CLOCK_KHZ == 18000
+# include "usbdrvasm18.inc"
+# elif USB_CFG_CLOCK_KHZ == 20000
+# include "usbdrvasm20.inc"
+# else
+# error "USB_CFG_CLOCK_KHZ is not one of the supported rates!"
+# endif
+#endif /* USB_CFG_CHECK_CRC */
--- /dev/null
+/* Name: usbdrvasm.asm
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2006-03-01
+ * Tabsize: 4
+ * Copyright: (c) 2006 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/*
+General Description:
+The IAR compiler/assembler system prefers assembler files with file extension
+".asm". We simply provide this file as an alias for usbdrvasm.S.
+
+Thanks to Oleg Semyonov for his help with the IAR tools port!
+*/
+
+#include "usbdrvasm.S"
+
+end
--- /dev/null
+/* Name: usbdrvasm12.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2004-12-29
+ * Tabsize: 4
+ * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 12 MHz version of the asssembler part of the USB driver. It
+requires a 12 MHz crystal (not a ceramic resonator and not a calibrated RC
+oscillator).
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+
+
+Timing constraints according to spec (in bit times):
+timing subject min max CPUcycles
+---------------------------------------------------------------------------
+EOP of OUT/SETUP to sync pattern of DATA0 (both rx) 2 16 16-128
+EOP of IN to sync pattern of DATA0 (rx, then tx) 2 7.5 16-60
+DATAx (rx) to ACK/NAK/STALL (tx) 2 7.5 16-60
+*/
+
+;Software-receiver engine. Strict timing! Don't change unless you can preserve timing!
+;interrupt response time: 4 cycles + insn running = 7 max if interrupts always enabled
+;max allowable interrupt latency: 34 cycles -> max 25 cycles interrupt disable
+;max stack usage: [ret(2), YL, SREG, YH, shift, x1, x2, x3, cnt, x4] = 11 bytes
+;Numbers in brackets are maximum cycles since SOF.
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG [sofError], YH, shift, x1, x2, x3, cnt
+ push YL ;2 [35] push only what is necessary to sync with edge ASAP
+ in YL, SREG ;1 [37]
+ push YL ;2 [39]
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+foundK:
+;{3, 5} after falling D- edge, average delay: 4 cycles [we want 4 for center sampling]
+;we have 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push YH ;2 [2]
+ lds YL, usbInputBufOffset;2 [4]
+ clr YH ;1 [5]
+ subi YL, lo8(-(usbRxBuf));1 [6]
+ sbci YH, hi8(-(usbRxBuf));1 [7]
+
+ sbis USBIN, USBMINUS ;1 [8] we want two bits K [sample 1 cycle too early]
+ rjmp haveTwoBitsK ;2 [10]
+ pop YH ;2 [11] undo the push from before
+ rjmp waitForK ;2 [13] this was not the end of sync, retry
+haveTwoBitsK:
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+ push shift ;2 [16]
+ push x1 ;2 [12]
+ push x2 ;2 [14]
+
+ in x1, USBIN ;1 [17] <-- sample bit 0
+ ldi shift, 0xff ;1 [18]
+ bst x1, USBMINUS ;1 [19]
+ bld shift, 0 ;1 [20]
+ push x3 ;2 [22]
+ push cnt ;2 [24]
+
+ in x2, USBIN ;1 [25] <-- sample bit 1
+ ser x3 ;1 [26] [inserted init instruction]
+ eor x1, x2 ;1 [27]
+ bst x1, USBMINUS ;1 [28]
+ bld shift, 1 ;1 [29]
+ ldi cnt, USB_BUFSIZE;1 [30] [inserted init instruction]
+ rjmp rxbit2 ;2 [32]
+
+;----------------------------------------------------------------------------
+; Receiver loop (numbers in brackets are cycles within byte after instr)
+;----------------------------------------------------------------------------
+
+unstuff0: ;1 (branch taken)
+ andi x3, ~0x01 ;1 [15]
+ mov x1, x2 ;1 [16] x2 contains last sampled (stuffed) bit
+ in x2, USBIN ;1 [17] <-- sample bit 1 again
+ ori shift, 0x01 ;1 [18]
+ rjmp didUnstuff0 ;2 [20]
+
+unstuff1: ;1 (branch taken)
+ mov x2, x1 ;1 [21] x1 contains last sampled (stuffed) bit
+ andi x3, ~0x02 ;1 [22]
+ ori shift, 0x02 ;1 [23]
+ nop ;1 [24]
+ in x1, USBIN ;1 [25] <-- sample bit 2 again
+ rjmp didUnstuff1 ;2 [27]
+
+unstuff2: ;1 (branch taken)
+ andi x3, ~0x04 ;1 [29]
+ ori shift, 0x04 ;1 [30]
+ mov x1, x2 ;1 [31] x2 contains last sampled (stuffed) bit
+ nop ;1 [32]
+ in x2, USBIN ;1 [33] <-- sample bit 3
+ rjmp didUnstuff2 ;2 [35]
+
+unstuff3: ;1 (branch taken)
+ in x2, USBIN ;1 [34] <-- sample stuffed bit 3 [one cycle too late]
+ andi x3, ~0x08 ;1 [35]
+ ori shift, 0x08 ;1 [36]
+ rjmp didUnstuff3 ;2 [38]
+
+unstuff4: ;1 (branch taken)
+ andi x3, ~0x10 ;1 [40]
+ in x1, USBIN ;1 [41] <-- sample stuffed bit 4
+ ori shift, 0x10 ;1 [42]
+ rjmp didUnstuff4 ;2 [44]
+
+unstuff5: ;1 (branch taken)
+ andi x3, ~0x20 ;1 [48]
+ in x2, USBIN ;1 [49] <-- sample stuffed bit 5
+ ori shift, 0x20 ;1 [50]
+ rjmp didUnstuff5 ;2 [52]
+
+unstuff6: ;1 (branch taken)
+ andi x3, ~0x40 ;1 [56]
+ in x1, USBIN ;1 [57] <-- sample stuffed bit 6
+ ori shift, 0x40 ;1 [58]
+ rjmp didUnstuff6 ;2 [60]
+
+; extra jobs done during bit interval:
+; bit 0: store, clear [SE0 is unreliable here due to bit dribbling in hubs]
+; bit 1: se0 check
+; bit 2: overflow check
+; bit 3: recovery from delay [bit 0 tasks took too long]
+; bit 4: none
+; bit 5: none
+; bit 6: none
+; bit 7: jump, eor
+rxLoop:
+ eor x3, shift ;1 [0] reconstruct: x3 is 0 at bit locations we changed, 1 at others
+ in x1, USBIN ;1 [1] <-- sample bit 0
+ st y+, x3 ;2 [3] store data
+ ser x3 ;1 [4]
+ nop ;1 [5]
+ eor x2, x1 ;1 [6]
+ bst x2, USBMINUS;1 [7]
+ bld shift, 0 ;1 [8]
+ in x2, USBIN ;1 [9] <-- sample bit 1 (or possibly bit 0 stuffed)
+ andi x2, USBMASK ;1 [10]
+ breq se0 ;1 [11] SE0 check for bit 1
+ andi shift, 0xf9 ;1 [12]
+didUnstuff0:
+ breq unstuff0 ;1 [13]
+ eor x1, x2 ;1 [14]
+ bst x1, USBMINUS;1 [15]
+ bld shift, 1 ;1 [16]
+rxbit2:
+ in x1, USBIN ;1 [17] <-- sample bit 2 (or possibly bit 1 stuffed)
+ andi shift, 0xf3 ;1 [18]
+ breq unstuff1 ;1 [19] do remaining work for bit 1
+didUnstuff1:
+ subi cnt, 1 ;1 [20]
+ brcs overflow ;1 [21] loop control
+ eor x2, x1 ;1 [22]
+ bst x2, USBMINUS;1 [23]
+ bld shift, 2 ;1 [24]
+ in x2, USBIN ;1 [25] <-- sample bit 3 (or possibly bit 2 stuffed)
+ andi shift, 0xe7 ;1 [26]
+ breq unstuff2 ;1 [27]
+didUnstuff2:
+ eor x1, x2 ;1 [28]
+ bst x1, USBMINUS;1 [29]
+ bld shift, 3 ;1 [30]
+didUnstuff3:
+ andi shift, 0xcf ;1 [31]
+ breq unstuff3 ;1 [32]
+ in x1, USBIN ;1 [33] <-- sample bit 4
+ eor x2, x1 ;1 [34]
+ bst x2, USBMINUS;1 [35]
+ bld shift, 4 ;1 [36]
+didUnstuff4:
+ andi shift, 0x9f ;1 [37]
+ breq unstuff4 ;1 [38]
+ nop2 ;2 [40]
+ in x2, USBIN ;1 [41] <-- sample bit 5
+ eor x1, x2 ;1 [42]
+ bst x1, USBMINUS;1 [43]
+ bld shift, 5 ;1 [44]
+didUnstuff5:
+ andi shift, 0x3f ;1 [45]
+ breq unstuff5 ;1 [46]
+ nop2 ;2 [48]
+ in x1, USBIN ;1 [49] <-- sample bit 6
+ eor x2, x1 ;1 [50]
+ bst x2, USBMINUS;1 [51]
+ bld shift, 6 ;1 [52]
+didUnstuff6:
+ cpi shift, 0x02 ;1 [53]
+ brlo unstuff6 ;1 [54]
+ nop2 ;2 [56]
+ in x2, USBIN ;1 [57] <-- sample bit 7
+ eor x1, x2 ;1 [58]
+ bst x1, USBMINUS;1 [59]
+ bld shift, 7 ;1 [60]
+didUnstuff7:
+ cpi shift, 0x04 ;1 [61]
+ brsh rxLoop ;2 [63] loop control
+unstuff7:
+ andi x3, ~0x80 ;1 [63]
+ ori shift, 0x80 ;1 [64]
+ in x2, USBIN ;1 [65] <-- sample stuffed bit 7
+ nop ;1 [66]
+ rjmp didUnstuff7 ;2 [68]
+
+macro POP_STANDARD ; 12 cycles
+ pop cnt
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop YH
+ endm
+macro POP_RETI ; 5 cycles
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+#include "asmcommon.inc"
+
+;----------------------------------------------------------------------------
+; Transmitting data
+;----------------------------------------------------------------------------
+
+txByteLoop:
+txBitloop:
+stuffN1Delay: ; [03]
+ ror shift ;[-5] [11] [59]
+ brcc doExorN1 ;[-4] [60]
+ subi x4, 1 ;[-3]
+ brne commonN1 ;[-2]
+ lsl shift ;[-1] compensate ror after rjmp stuffDelay
+ nop ;[00] stuffing consists of just waiting 8 cycles
+ rjmp stuffN1Delay ;[01] after ror, C bit is reliably clear
+
+sendNakAndReti: ;0 [-19] 19 cycles until SOP
+ ldi x3, USBPID_NAK ;1 [-18]
+ rjmp usbSendX3 ;2 [-16]
+sendAckAndReti: ;0 [-19] 19 cycles until SOP
+ ldi x3, USBPID_ACK ;1 [-18]
+ rjmp usbSendX3 ;2 [-16]
+sendCntAndReti: ;0 [-17] 17 cycles until SOP
+ mov x3, cnt ;1 [-16]
+usbSendX3: ;0 [-16]
+ ldi YL, 20 ;1 [-15] 'x3' is R20
+ ldi YH, 0 ;1 [-14]
+ ldi cnt, 2 ;1 [-13]
+; rjmp usbSendAndReti fallthrough
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1) or USBOUT = 0x01
+; K = (D+ = 1), (D- = 0) or USBOUT = 0x02
+; Spec allows 7.5 bit times from EOP to SOP for replies (= 60 cycles)
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte
+;uses: x1...x2, x4, shift, cnt, Y [x1 = mirror USBOUT, x2 = USBMASK, x4 = bitstuff cnt]
+;Numbers in brackets are time since first bit of sync pattern is sent (start of instruction)
+usbSendAndReti:
+ in x2, USBDDR ;[-12] 12 cycles until SOP
+ ori x2, USBMASK ;[-11]
+ sbi USBOUT, USBMINUS ;[-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ out USBDDR, x2 ;[-8] <--- acquire bus
+ in x1, USBOUT ;[-7] port mirror for tx loop
+ ldi shift, 0x40 ;[-6] sync byte is first byte sent (we enter loop after ror)
+ ldi x2, USBMASK ;[-5]
+ push x4 ;[-4]
+doExorN1:
+ eor x1, x2 ;[-2] [06] [62]
+ ldi x4, 6 ;[-1] [07] [63]
+commonN1:
+stuffN2Delay:
+ out USBOUT, x1 ;[00] [08] [64] <--- set bit
+ ror shift ;[01]
+ brcc doExorN2 ;[02]
+ subi x4, 1 ;[03]
+ brne commonN2 ;[04]
+ lsl shift ;[05] compensate ror after rjmp stuffDelay
+ rjmp stuffN2Delay ;[06] after ror, C bit is reliably clear
+doExorN2:
+ eor x1, x2 ;[04] [12]
+ ldi x4, 6 ;[05] [13]
+commonN2:
+ nop ;[06] [14]
+ subi cnt, 171 ;[07] [15] trick: (3 * 171) & 0xff = 1
+ out USBOUT, x1 ;[08] [16] <--- set bit
+ brcs txBitloop ;[09] [25] [41]
+
+stuff6Delay:
+ ror shift ;[42] [50]
+ brcc doExor6 ;[43]
+ subi x4, 1 ;[44]
+ brne common6 ;[45]
+ lsl shift ;[46] compensate ror after rjmp stuffDelay
+ nop ;[47] stuffing consists of just waiting 8 cycles
+ rjmp stuff6Delay ;[48] after ror, C bit is reliably clear
+doExor6:
+ eor x1, x2 ;[45] [53]
+ ldi x4, 6 ;[46]
+common6:
+stuff7Delay:
+ ror shift ;[47] [55]
+ out USBOUT, x1 ;[48] <--- set bit
+ brcc doExor7 ;[49]
+ subi x4, 1 ;[50]
+ brne common7 ;[51]
+ lsl shift ;[52] compensate ror after rjmp stuffDelay
+ rjmp stuff7Delay ;[53] after ror, C bit is reliably clear
+doExor7:
+ eor x1, x2 ;[51] [59]
+ ldi x4, 6 ;[52]
+common7:
+ ld shift, y+ ;[53]
+ tst cnt ;[55]
+ out USBOUT, x1 ;[56] <--- set bit
+ brne txByteLoop ;[57]
+
+;make SE0:
+ cbr x1, USBMASK ;[58] prepare SE0 [spec says EOP may be 15 to 18 cycles]
+ lds x2, usbNewDeviceAddr;[59]
+ lsl x2 ;[61] we compare with left shifted address
+ subi YL, 2 + 20 ;[62] Only assign address on data packets, not ACK/NAK in x3
+ sbci YH, 0 ;[63]
+ out USBOUT, x1 ;[00] <-- out SE0 -- from now 2 bits = 16 cycles until bus idle
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ breq skipAddrAssign ;[01]
+ sts usbDeviceAddr, x2 ; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[03] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[04]
+ ori x1, USBIDLE ;[05]
+ in x2, USBDDR ;[06]
+ cbr x2, USBMASK ;[07] set both pins to input
+ mov x3, x1 ;[08]
+ cbr x3, USBMASK ;[09] configure no pullup on both pins
+ pop x4 ;[10]
+ nop2 ;[12]
+ nop2 ;[14]
+ out USBOUT, x1 ;[16] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[17] <-- release bus now
+ out USBOUT, x3 ;[18] <-- ensure no pull-up resistors are active
+ rjmp doReturn
--- /dev/null
+/* Name: usbdrvasm128.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2008-10-11
+ * Tabsize: 4
+ * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 12.8 MHz version of the USB driver. It is intended for use
+with the internal RC oscillator. Although 12.8 MHz is outside the guaranteed
+calibration range of the oscillator, almost all AVRs can reach this frequency.
+This version contains a phase locked loop in the receiver routine to cope with
+slight clock rate deviations of up to +/- 1%.
+
+See usbdrv.h for a description of the entire driver.
+
+LIMITATIONS
+===========
+Although it may seem very handy to save the crystal and use the internal
+RC oscillator of the CPU, this method (and this module) has some serious
+limitations:
+(1) The guaranteed calibration range of the oscillator is only 8.1 MHz.
+They typical range is 14.5 MHz and most AVRs can actually reach this rate.
+(2) Writing EEPROM and Flash may be unreliable (short data lifetime) since
+the write procedure is timed from the RC oscillator.
+(3) End Of Packet detection (SE0) should be in bit 1, bit it is only checked
+if bits 0 and 1 both read as 0 on D- and D+ read as 0 in the middle. This may
+cause problems with old hubs which delay SE0 by up to one cycle.
+(4) Code size is much larger than that of the other modules.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+
+Implementation notes:
+======================
+min frequency: 67 cycles for 8 bit -> 12.5625 MHz
+max frequency: 69.286 cycles for 8 bit -> 12.99 MHz
+nominal frequency: 12.77 MHz ( = sqrt(min * max))
+
+sampling positions: (next even number in range [+/- 0.5])
+cycle index range: 0 ... 66
+bits:
+.5, 8.875, 17.25, 25.625, 34, 42.375, 50.75, 59.125
+[0/1], [9], [17], [25/+26], [34], [+42/43], [51], [59]
+
+bit number: 0 1 2 3 4 5 6 7
+spare cycles 1 2 1 2 1 1 1 0
+
+operations to perform: duration cycle
+ ----------------
+ eor fix, shift 1 -> 00
+ andi phase, USBMASK 1 -> 08
+ breq se0 1 -> 16 (moved to 11)
+ st y+, data 2 -> 24, 25
+ mov data, fix 1 -> 33
+ ser data 1 -> 41
+ subi cnt, 1 1 -> 49
+ brcs overflow 1 -> 50
+
+layout of samples and operations:
+[##] = sample bit
+<##> = sample phase
+*##* = operation
+
+0: *00* [01] 02 03 04 <05> 06 07
+1: *08* [09] 10 11 12 <13> 14 15 *16*
+2: [17] 18 19 20 <21> 22 23
+3: *24* *25* [26] 27 28 29 <30> 31 32
+4: *33* [34] 35 36 37 <38> 39 40
+5: *41* [42] 43 44 45 <46> 47 48
+6: *49* *50* [51] 52 53 54 <55> 56 57 58
+7: [59] 60 61 62 <63> 64 65 66
+*****************************************************************************/
+
+/* we prefer positive expressions (do if condition) instead of negative
+ * (skip if condition), therefore use defines for skip instructions:
+ */
+#define ifioclr sbis
+#define ifioset sbic
+#define ifrclr sbrs
+#define ifrset sbrc
+
+/* The registers "fix" and "data" swap their meaning during the loop. Use
+ * defines to keep their name constant.
+ */
+#define fix x2
+#define data x1
+#undef phase /* phase has a default definition to x4 */
+#define phase x3
+
+
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG [sofError], YH, shift, x1, x2, x3, cnt, r0
+ push YL ;2 push only what is necessary to sync with edge ASAP
+ in YL, SREG ;1
+ push YL ;2
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS ;[0]
+ rjmp foundK ;[1]
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+
+foundK:
+;{3, 5} after falling D- edge, average delay: 4 cycles [we want 4 for center sampling]
+;we have 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push YH ;[2]
+ lds YL, usbInputBufOffset;[4]
+ clr YH ;[6]
+ subi YL, lo8(-(usbRxBuf));[7]
+ sbci YH, hi8(-(usbRxBuf));[8]
+
+ sbis USBIN, USBMINUS ;[9] we want two bits K [we want to sample at 8 + 4 - 1.5 = 10.5]
+ rjmp haveTwoBitsK ;[10]
+ pop YH ;[11] undo the push from before
+ rjmp waitForK ;[13] this was not the end of sync, retry
+haveTwoBitsK:
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+#define fix x2
+#define data x1
+
+ push shift ;[12]
+ push x1 ;[14]
+ push x2 ;[16]
+ ldi shift, 0x80 ;[18] prevent bit-unstuffing but init low bits to 0
+ ifioset USBIN, USBMINUS ;[19] [01] <--- bit 0 [10.5 + 8 = 18.5]
+ ori shift, 1<<0 ;[02]
+ push x3 ;[03]
+ push cnt ;[05]
+ push r0 ;[07]
+ ifioset USBIN, USBMINUS ;[09] <--- bit 1
+ ori shift, 1<<1 ;[10]
+ ser fix ;[11]
+ ldi cnt, USB_BUFSIZE ;[12]
+ mov data, shift ;[13]
+ lsl shift ;[14]
+ nop2 ;[15]
+ ifioset USBIN, USBMINUS ;[17] <--- bit 2
+ ori data, 3<<2 ;[18] store in bit 2 AND bit 3
+ eor shift, data ;[19] do nrzi decoding
+ andi data, 1<<3 ;[20]
+ in phase, USBIN ;[21] <- phase
+ brne jumpToEntryAfterSet ;[22] if USBMINS at bit 3 was 1
+ nop ;[23]
+ rjmp entryAfterClr ;[24]
+jumpToEntryAfterSet:
+ rjmp entryAfterSet ;[24]
+
+;----------------------------------------------------------------------------
+; Receiver loop (numbers in brackets are cycles within byte after instr)
+;----------------------------------------------------------------------------
+#undef fix
+#define fix x1
+#undef data
+#define data x2
+
+bit7IsSet:
+ ifrclr phase, USBMINUS ;[62] check phase only if D- changed
+ lpm ;[63]
+ in phase, USBIN ;[64] <- phase (one cycle too late)
+ ori shift, 1 << 7 ;[65]
+ nop ;[66]
+;;;;rjmp bit0AfterSet ; -> [00] == [67] moved block up to save jump
+bit0AfterSet:
+ eor fix, shift ;[00]
+#undef fix
+#define fix x2
+#undef data
+#define data x1 /* we now have result in data, fix is reset to 0xff */
+ ifioclr USBIN, USBMINUS ;[01] <--- sample 0
+ rjmp bit0IsClr ;[02]
+ andi shift, ~(7 << 0) ;[03]
+ breq unstuff0s ;[04]
+ in phase, USBIN ;[05] <- phase
+ rjmp bit1AfterSet ;[06]
+unstuff0s:
+ in phase, USBIN ;[06] <- phase (one cycle too late)
+ andi fix, ~(1 << 0) ;[07]
+ ifioclr USBIN, USBMINUS ;[00]
+ ifioset USBIN, USBPLUS ;[01]
+ rjmp bit0IsClr ;[02] executed if first expr false or second true
+se0AndStore: ; executed only if both bits 0
+ st y+, x1 ;[15/17] cycles after start of byte
+ rjmp se0 ;[17/19]
+
+bit0IsClr:
+ ifrset phase, USBMINUS ;[04] check phase only if D- changed
+ lpm ;[05]
+ in phase, USBIN ;[06] <- phase (one cycle too late)
+ ori shift, 1 << 0 ;[07]
+bit1AfterClr:
+ andi phase, USBMASK ;[08]
+ ifioset USBIN, USBMINUS ;[09] <--- sample 1
+ rjmp bit1IsSet ;[10]
+ breq se0AndStore ;[11] if D- was 0 in bits 0 AND 1 and D+ was 0 in between, we have SE0
+ andi shift, ~(7 << 1) ;[12]
+ in phase, USBIN ;[13] <- phase
+ breq unstuff1c ;[14]
+ rjmp bit2AfterClr ;[15]
+unstuff1c:
+ andi fix, ~(1 << 1) ;[16]
+ nop2 ;[08]
+ nop2 ;[10]
+bit1IsSet:
+ ifrclr phase, USBMINUS ;[12] check phase only if D- changed
+ lpm ;[13]
+ in phase, USBIN ;[14] <- phase (one cycle too late)
+ ori shift, 1 << 1 ;[15]
+ nop ;[16]
+bit2AfterSet:
+ ifioclr USBIN, USBMINUS ;[17] <--- sample 2
+ rjmp bit2IsClr ;[18]
+ andi shift, ~(7 << 2) ;[19]
+ breq unstuff2s ;[20]
+ in phase, USBIN ;[21] <- phase
+ rjmp bit3AfterSet ;[22]
+unstuff2s:
+ in phase, USBIN ;[22] <- phase (one cycle too late)
+ andi fix, ~(1 << 2) ;[23]
+ nop2 ;[16]
+ nop2 ;[18]
+bit2IsClr:
+ ifrset phase, USBMINUS ;[20] check phase only if D- changed
+ lpm ;[21]
+ in phase, USBIN ;[22] <- phase (one cycle too late)
+ ori shift, 1 << 2 ;[23]
+bit3AfterClr:
+ st y+, data ;[24]
+entryAfterClr:
+ ifioset USBIN, USBMINUS ;[26] <--- sample 3
+ rjmp bit3IsSet ;[27]
+ andi shift, ~(7 << 3) ;[28]
+ breq unstuff3c ;[29]
+ in phase, USBIN ;[30] <- phase
+ rjmp bit4AfterClr ;[31]
+unstuff3c:
+ in phase, USBIN ;[31] <- phase (one cycle too late)
+ andi fix, ~(1 << 3) ;[32]
+ nop2 ;[25]
+ nop2 ;[27]
+bit3IsSet:
+ ifrclr phase, USBMINUS ;[29] check phase only if D- changed
+ lpm ;[30]
+ in phase, USBIN ;[31] <- phase (one cycle too late)
+ ori shift, 1 << 3 ;[32]
+bit4AfterSet:
+ mov data, fix ;[33] undo this move by swapping defines
+#undef fix
+#define fix x1
+#undef data
+#define data x2
+ ifioclr USBIN, USBMINUS ;[34] <--- sample 4
+ rjmp bit4IsClr ;[35]
+ andi shift, ~(7 << 4) ;[36]
+ breq unstuff4s ;[37]
+ in phase, USBIN ;[38] <- phase
+ rjmp bit5AfterSet ;[39]
+unstuff4s:
+ in phase, USBIN ;[39] <- phase (one cycle too late)
+ andi fix, ~(1 << 4) ;[40]
+ nop2 ;[33]
+ nop2 ;[35]
+bit4IsClr:
+ ifrset phase, USBMINUS ;[37] check phase only if D- changed
+ lpm ;[38]
+ in phase, USBIN ;[39] <- phase (one cycle too late)
+ ori shift, 1 << 4 ;[40]
+bit5AfterClr:
+ ser data ;[41]
+ ifioset USBIN, USBMINUS ;[42] <--- sample 5
+ rjmp bit5IsSet ;[43]
+ andi shift, ~(7 << 5) ;[44]
+ breq unstuff5c ;[45]
+ in phase, USBIN ;[46] <- phase
+ rjmp bit6AfterClr ;[47]
+unstuff5c:
+ in phase, USBIN ;[47] <- phase (one cycle too late)
+ andi fix, ~(1 << 5) ;[48]
+ nop2 ;[41]
+ nop2 ;[43]
+bit5IsSet:
+ ifrclr phase, USBMINUS ;[45] check phase only if D- changed
+ lpm ;[46]
+ in phase, USBIN ;[47] <- phase (one cycle too late)
+ ori shift, 1 << 5 ;[48]
+bit6AfterSet:
+ subi cnt, 1 ;[49]
+ brcs jumpToOverflow ;[50]
+ ifioclr USBIN, USBMINUS ;[51] <--- sample 6
+ rjmp bit6IsClr ;[52]
+ andi shift, ~(3 << 6) ;[53]
+ cpi shift, 2 ;[54]
+ in phase, USBIN ;[55] <- phase
+ brlt unstuff6s ;[56]
+ rjmp bit7AfterSet ;[57]
+
+jumpToOverflow:
+ rjmp overflow
+
+unstuff6s:
+ andi fix, ~(1 << 6) ;[50]
+ lpm ;[51]
+bit6IsClr:
+ ifrset phase, USBMINUS ;[54] check phase only if D- changed
+ lpm ;[55]
+ in phase, USBIN ;[56] <- phase (one cycle too late)
+ ori shift, 1 << 6 ;[57]
+ nop ;[58]
+bit7AfterClr:
+ ifioset USBIN, USBMINUS ;[59] <--- sample 7
+ rjmp bit7IsSet ;[60]
+ andi shift, ~(1 << 7) ;[61]
+ cpi shift, 4 ;[62]
+ in phase, USBIN ;[63] <- phase
+ brlt unstuff7c ;[64]
+ rjmp bit0AfterClr ;[65] -> [00] == [67]
+unstuff7c:
+ andi fix, ~(1 << 7) ;[58]
+ nop ;[59]
+ rjmp bit7IsSet ;[60]
+
+bit7IsClr:
+ ifrset phase, USBMINUS ;[62] check phase only if D- changed
+ lpm ;[63]
+ in phase, USBIN ;[64] <- phase (one cycle too late)
+ ori shift, 1 << 7 ;[65]
+ nop ;[66]
+;;;;rjmp bit0AfterClr ; -> [00] == [67] moved block up to save jump
+bit0AfterClr:
+ eor fix, shift ;[00]
+#undef fix
+#define fix x2
+#undef data
+#define data x1 /* we now have result in data, fix is reset to 0xff */
+ ifioset USBIN, USBMINUS ;[01] <--- sample 0
+ rjmp bit0IsSet ;[02]
+ andi shift, ~(7 << 0) ;[03]
+ breq unstuff0c ;[04]
+ in phase, USBIN ;[05] <- phase
+ rjmp bit1AfterClr ;[06]
+unstuff0c:
+ in phase, USBIN ;[06] <- phase (one cycle too late)
+ andi fix, ~(1 << 0) ;[07]
+ ifioclr USBIN, USBMINUS ;[00]
+ ifioset USBIN, USBPLUS ;[01]
+ rjmp bit0IsSet ;[02] executed if first expr false or second true
+ rjmp se0AndStore ;[03] executed only if both bits 0
+bit0IsSet:
+ ifrclr phase, USBMINUS ;[04] check phase only if D- changed
+ lpm ;[05]
+ in phase, USBIN ;[06] <- phase (one cycle too late)
+ ori shift, 1 << 0 ;[07]
+bit1AfterSet:
+ andi shift, ~(7 << 1) ;[08] compensated by "ori shift, 1<<1" if bit1IsClr
+ ifioclr USBIN, USBMINUS ;[09] <--- sample 1
+ rjmp bit1IsClr ;[10]
+ breq unstuff1s ;[11]
+ nop2 ;[12] do not check for SE0 if bit 0 was 1
+ in phase, USBIN ;[14] <- phase (one cycle too late)
+ rjmp bit2AfterSet ;[15]
+unstuff1s:
+ in phase, USBIN ;[13] <- phase
+ andi fix, ~(1 << 1) ;[14]
+ lpm ;[07]
+ nop2 ;[10]
+bit1IsClr:
+ ifrset phase, USBMINUS ;[12] check phase only if D- changed
+ lpm ;[13]
+ in phase, USBIN ;[14] <- phase (one cycle too late)
+ ori shift, 1 << 1 ;[15]
+ nop ;[16]
+bit2AfterClr:
+ ifioset USBIN, USBMINUS ;[17] <--- sample 2
+ rjmp bit2IsSet ;[18]
+ andi shift, ~(7 << 2) ;[19]
+ breq unstuff2c ;[20]
+ in phase, USBIN ;[21] <- phase
+ rjmp bit3AfterClr ;[22]
+unstuff2c:
+ in phase, USBIN ;[22] <- phase (one cycle too late)
+ andi fix, ~(1 << 2) ;[23]
+ nop2 ;[16]
+ nop2 ;[18]
+bit2IsSet:
+ ifrclr phase, USBMINUS ;[20] check phase only if D- changed
+ lpm ;[21]
+ in phase, USBIN ;[22] <- phase (one cycle too late)
+ ori shift, 1 << 2 ;[23]
+bit3AfterSet:
+ st y+, data ;[24]
+entryAfterSet:
+ ifioclr USBIN, USBMINUS ;[26] <--- sample 3
+ rjmp bit3IsClr ;[27]
+ andi shift, ~(7 << 3) ;[28]
+ breq unstuff3s ;[29]
+ in phase, USBIN ;[30] <- phase
+ rjmp bit4AfterSet ;[31]
+unstuff3s:
+ in phase, USBIN ;[31] <- phase (one cycle too late)
+ andi fix, ~(1 << 3) ;[32]
+ nop2 ;[25]
+ nop2 ;[27]
+bit3IsClr:
+ ifrset phase, USBMINUS ;[29] check phase only if D- changed
+ lpm ;[30]
+ in phase, USBIN ;[31] <- phase (one cycle too late)
+ ori shift, 1 << 3 ;[32]
+bit4AfterClr:
+ mov data, fix ;[33] undo this move by swapping defines
+#undef fix
+#define fix x1
+#undef data
+#define data x2
+ ifioset USBIN, USBMINUS ;[34] <--- sample 4
+ rjmp bit4IsSet ;[35]
+ andi shift, ~(7 << 4) ;[36]
+ breq unstuff4c ;[37]
+ in phase, USBIN ;[38] <- phase
+ rjmp bit5AfterClr ;[39]
+unstuff4c:
+ in phase, USBIN ;[39] <- phase (one cycle too late)
+ andi fix, ~(1 << 4) ;[40]
+ nop2 ;[33]
+ nop2 ;[35]
+bit4IsSet:
+ ifrclr phase, USBMINUS ;[37] check phase only if D- changed
+ lpm ;[38]
+ in phase, USBIN ;[39] <- phase (one cycle too late)
+ ori shift, 1 << 4 ;[40]
+bit5AfterSet:
+ ser data ;[41]
+ ifioclr USBIN, USBMINUS ;[42] <--- sample 5
+ rjmp bit5IsClr ;[43]
+ andi shift, ~(7 << 5) ;[44]
+ breq unstuff5s ;[45]
+ in phase, USBIN ;[46] <- phase
+ rjmp bit6AfterSet ;[47]
+unstuff5s:
+ in phase, USBIN ;[47] <- phase (one cycle too late)
+ andi fix, ~(1 << 5) ;[48]
+ nop2 ;[41]
+ nop2 ;[43]
+bit5IsClr:
+ ifrset phase, USBMINUS ;[45] check phase only if D- changed
+ lpm ;[46]
+ in phase, USBIN ;[47] <- phase (one cycle too late)
+ ori shift, 1 << 5 ;[48]
+bit6AfterClr:
+ subi cnt, 1 ;[49]
+ brcs overflow ;[50]
+ ifioset USBIN, USBMINUS ;[51] <--- sample 6
+ rjmp bit6IsSet ;[52]
+ andi shift, ~(3 << 6) ;[53]
+ cpi shift, 2 ;[54]
+ in phase, USBIN ;[55] <- phase
+ brlt unstuff6c ;[56]
+ rjmp bit7AfterClr ;[57]
+unstuff6c:
+ andi fix, ~(1 << 6) ;[50]
+ lpm ;[51]
+bit6IsSet:
+ ifrclr phase, USBMINUS ;[54] check phase only if D- changed
+ lpm ;[55]
+ in phase, USBIN ;[56] <- phase (one cycle too late)
+ ori shift, 1 << 6 ;[57]
+bit7AfterSet:
+ ifioclr USBIN, USBMINUS ;[59] <--- sample 7
+ rjmp bit7IsClr ;[60]
+ andi shift, ~(1 << 7) ;[61]
+ cpi shift, 4 ;[62]
+ in phase, USBIN ;[63] <- phase
+ brlt unstuff7s ;[64]
+ rjmp bit0AfterSet ;[65] -> [00] == [67]
+unstuff7s:
+ andi fix, ~(1 << 7) ;[58]
+ nop ;[59]
+ rjmp bit7IsClr ;[60]
+
+macro POP_STANDARD ; 14 cycles
+ pop r0
+ pop cnt
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop YH
+ endm
+macro POP_RETI ; 5 cycles
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+#include "asmcommon.inc"
+
+;----------------------------------------------------------------------------
+; Transmitting data
+;----------------------------------------------------------------------------
+
+txByteLoop:
+txBitloop:
+stuffN1Delay: ; [03]
+ ror shift ;[-5] [11] [63]
+ brcc doExorN1 ;[-4] [64]
+ subi x3, 1 ;[-3]
+ brne commonN1 ;[-2]
+ lsl shift ;[-1] compensate ror after rjmp stuffDelay
+ nop ;[00] stuffing consists of just waiting 8 cycles
+ rjmp stuffN1Delay ;[01] after ror, C bit is reliably clear
+
+sendNakAndReti:
+ ldi cnt, USBPID_NAK ;[-19]
+ rjmp sendCntAndReti ;[-18]
+sendAckAndReti:
+ ldi cnt, USBPID_ACK ;[-17]
+sendCntAndReti:
+ mov r0, cnt ;[-16]
+ ldi YL, 0 ;[-15] R0 address is 0
+ ldi YH, 0 ;[-14]
+ ldi cnt, 2 ;[-13]
+; rjmp usbSendAndReti fallthrough
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1) or USBOUT = 0x01
+; K = (D+ = 1), (D- = 0) or USBOUT = 0x02
+; Spec allows 7.5 bit times from EOP to SOP for replies (= 60 cycles)
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte
+;uses: x1...x3, shift, cnt, Y [x1 = mirror USBOUT, x2 = USBMASK, x3 = bitstuff cnt]
+;Numbers in brackets are time since first bit of sync pattern is sent (start of instruction)
+usbSendAndReti:
+ in x2, USBDDR ;[-10] 10 cycles until SOP
+ ori x2, USBMASK ;[-9]
+ sbi USBOUT, USBMINUS ;[-8] prepare idle state; D+ and D- must have been 0 (no pullups)
+ out USBDDR, x2 ;[-6] <--- acquire bus
+ in x1, USBOUT ;[-5] port mirror for tx loop
+ ldi shift, 0x40 ;[-4] sync byte is first byte sent (we enter loop after ror)
+ ldi x2, USBMASK ;[-3]
+doExorN1:
+ eor x1, x2 ;[-2] [06] [62]
+ ldi x3, 6 ;[-1] [07] [63]
+commonN1:
+stuffN2Delay:
+ out USBOUT, x1 ;[00] [08] [64] <--- set bit
+ ror shift ;[01]
+ brcc doExorN2 ;[02]
+ subi x3, 1 ;[03]
+ brne commonN2 ;[04]
+ lsl shift ;[05] compensate ror after rjmp stuffDelay
+ rjmp stuffN2Delay ;[06] after ror, C bit is reliably clear
+doExorN2:
+ eor x1, x2 ;[04] [12]
+ ldi x3, 6 ;[05] [13]
+commonN2:
+ nop2 ;[06] [14]
+ subi cnt, 171 ;[08] [16] trick: (3 * 171) & 0xff = 1
+ out USBOUT, x1 ;[09] [17] <--- set bit
+ brcs txBitloop ;[10] [27] [44]
+
+stuff6Delay:
+ ror shift ;[45] [53]
+ brcc doExor6 ;[46]
+ subi x3, 1 ;[47]
+ brne common6 ;[48]
+ lsl shift ;[49] compensate ror after rjmp stuffDelay
+ nop ;[50] stuffing consists of just waiting 8 cycles
+ rjmp stuff6Delay ;[51] after ror, C bit is reliably clear
+doExor6:
+ eor x1, x2 ;[48] [56]
+ ldi x3, 6 ;[49]
+common6:
+stuff7Delay:
+ ror shift ;[50] [58]
+ out USBOUT, x1 ;[51] <--- set bit
+ brcc doExor7 ;[52]
+ subi x3, 1 ;[53]
+ brne common7 ;[54]
+ lsl shift ;[55] compensate ror after rjmp stuffDelay
+ rjmp stuff7Delay ;[56] after ror, C bit is reliably clear
+doExor7:
+ eor x1, x2 ;[54] [62]
+ ldi x3, 6 ;[55]
+common7:
+ ld shift, y+ ;[56]
+ nop ;[58]
+ tst cnt ;[59]
+ out USBOUT, x1 ;[60] [00]<--- set bit
+ brne txByteLoop ;[61] [01]
+;make SE0:
+ cbr x1, USBMASK ;[02] prepare SE0 [spec says EOP may be 15 to 18 cycles]
+ lds x2, usbNewDeviceAddr;[03]
+ lsl x2 ;[05] we compare with left shifted address
+ subi YL, 2 + 0 ;[06] Only assign address on data packets, not ACK/NAK in r0
+ sbci YH, 0 ;[07]
+ out USBOUT, x1 ;[00] <-- out SE0 -- from now 2 bits = 16 cycles until bus idle
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ breq skipAddrAssign ;[01]
+ sts usbDeviceAddr, x2 ; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[03] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[04]
+ ori x1, USBIDLE ;[05]
+ in x2, USBDDR ;[06]
+ cbr x2, USBMASK ;[07] set both pins to input
+ mov x3, x1 ;[08]
+ cbr x3, USBMASK ;[09] configure no pullup on both pins
+ lpm ;[10]
+ lpm ;[13]
+ out USBOUT, x1 ;[16] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[17] <-- release bus now
+ out USBOUT, x3 ;[18] <-- ensure no pull-up resistors are active
+ rjmp doReturn
+
+
+
+/*****************************************************************************
+The following PHP script generates a code skeleton for the receiver routine:
+
+<?php
+
+function printCmdBuffer($thisBit)
+{
+global $cycle;
+
+ $nextBit = ($thisBit + 1) % 8;
+ $s = ob_get_contents();
+ ob_end_clean();
+ $s = str_replace("#", $thisBit, $s);
+ $s = str_replace("@", $nextBit, $s);
+ $lines = explode("\n", $s);
+ for($i = 0; $i < count($lines); $i++){
+ $s = $lines[$i];
+ if(ereg("\\[([0-9-][0-9])\\]", $s, $regs)){
+ $c = $cycle + (int)$regs[1];
+ $s = ereg_replace("\\[[0-9-][0-9]\\]", sprintf("[%02d]", $c), $s);
+ }
+ if(strlen($s) > 0)
+ echo "$s\n";
+ }
+}
+
+function printBit($isAfterSet, $bitNum)
+{
+ ob_start();
+ if($isAfterSet){
+?>
+ ifioclr USBIN, USBMINUS ;[00] <--- sample
+ rjmp bit#IsClr ;[01]
+ andi shift, ~(7 << #) ;[02]
+ breq unstuff#s ;[03]
+ in phase, USBIN ;[04] <- phase
+ rjmp bit@AfterSet ;[05]
+unstuff#s:
+ in phase, USBIN ;[05] <- phase (one cycle too late)
+ andi fix, ~(1 << #) ;[06]
+ nop2 ;[-1]
+ nop2 ;[01]
+bit#IsClr:
+ ifrset phase, USBMINUS ;[03] check phase only if D- changed
+ lpm ;[04]
+ in phase, USBIN ;[05] <- phase (one cycle too late)
+ ori shift, 1 << # ;[06]
+<?php
+ }else{
+?>
+ ifioset USBIN, USBMINUS ;[00] <--- sample
+ rjmp bit#IsSet ;[01]
+ andi shift, ~(7 << #) ;[02]
+ breq unstuff#c ;[03]
+ in phase, USBIN ;[04] <- phase
+ rjmp bit@AfterClr ;[05]
+unstuff#c:
+ in phase, USBIN ;[05] <- phase (one cycle too late)
+ andi fix, ~(1 << #) ;[06]
+ nop2 ;[-1]
+ nop2 ;[01]
+bit#IsSet:
+ ifrclr phase, USBMINUS ;[03] check phase only if D- changed
+ lpm ;[04]
+ in phase, USBIN ;[05] <- phase (one cycle too late)
+ ori shift, 1 << # ;[06]
+<?php
+ }
+ printCmdBuffer($bitNum);
+}
+
+$bitStartCycles = array(1, 9, 17, 26, 34, 42, 51, 59);
+for($i = 0; $i < 16; $i++){
+ $bit = $i % 8;
+ $emitClrCode = ($i + (int)($i / 8)) % 2;
+ $cycle = $bitStartCycles[$bit];
+ if($emitClrCode){
+ printf("bit%dAfterClr:\n", $bit);
+ }else{
+ printf("bit%dAfterSet:\n", $bit);
+ }
+ ob_start();
+ echo " ***** ;[-1]\n";
+ printCmdBuffer($bit);
+ printBit(!$emitClrCode, $bit);
+ if($i == 7)
+ echo "\n";
+}
+
+?>
+*****************************************************************************/
--- /dev/null
+/* Name: usbdrvasm15.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: contributed by V. Bosch
+ * Creation Date: 2007-08-06
+ * Tabsize: 4
+ * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 15 MHz version of the asssembler part of the USB driver. It
+requires a 15 MHz crystal (not a ceramic resonator and not a calibrated RC
+oscillator).
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+*/
+
+;max stack usage: [ret(2), YL, SREG, YH, bitcnt, shift, x1, x2, x3, x4, cnt] = 12 bytes
+;nominal frequency: 15 MHz -> 10.0 cycles per bit, 80.0 cycles per byte
+; Numbers in brackets are clocks counted from center of last sync bit
+; when instruction starts
+
+;----------------------------------------------------------------------------
+; order of registers pushed:
+; YL, SREG [sofError] YH, shift, x1, x2, x3, bitcnt, cnt, x4
+;----------------------------------------------------------------------------
+USB_INTR_VECTOR:
+ push YL ;2 push only what is necessary to sync with edge ASAP
+ in YL, SREG ;1
+ push YL ;2
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;
+; sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+; sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+;-------------------------------------------------------------------------------
+; The following code results in a sampling window of < 1/4 bit
+; which meets the spec.
+;-------------------------------------------------------------------------------
+waitForK: ;-
+ sbis USBIN, USBMINUS ;1 [00] <-- sample
+ rjmp foundK ;2 [01]
+ sbis USBIN, USBMINUS ; <-- sample
+ rjmp foundK
+ sbis USBIN, USBMINUS ; <-- sample
+ rjmp foundK
+ sbis USBIN, USBMINUS ; <-- sample
+ rjmp foundK
+ sbis USBIN, USBMINUS ; <-- sample
+ rjmp foundK
+ sbis USBIN, USBMINUS ; <-- sample
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+;------------------------------------------------------------------------------
+; {3, 5} after falling D- edge, average delay: 4 cycles [we want 5 for
+; center sampling]
+; we have 1 bit time for setup purposes, then sample again.
+; Numbers in brackets are cycles from center of first sync (double K)
+; bit after the instruction
+;------------------------------------------------------------------------------
+foundK: ;- [02]
+ lds YL, usbInputBufOffset;2 [03+04] tx loop
+ push YH ;2 [05+06]
+ clr YH ;1 [07]
+ subi YL, lo8(-(usbRxBuf)) ;1 [08] [rx loop init]
+ sbci YH, hi8(-(usbRxBuf)) ;1 [09] [rx loop init]
+ push shift ;2 [10+11]
+ ser shift ;1 [12]
+ sbis USBIN, USBMINUS ;1 [-1] [13] <--sample:we want two bits K (sample 1 cycle too early)
+ rjmp haveTwoBitsK ;2 [00] [14]
+ pop shift ;2 [15+16] undo the push from before
+ pop YH ;2 [17+18] undo the push from before
+ rjmp waitForK ;2 [19+20] this was not the end of sync, retry
+; The entire loop from waitForK until rjmp waitForK above must not exceed two
+; bit times (= 20 cycles).
+
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+haveTwoBitsK: ;- [01]
+ push x1 ;2 [02+03]
+ push x2 ;2 [04+05]
+ push x3 ;2 [06+07]
+ push bitcnt ;2 [08+09]
+ in x1, USBIN ;1 [00] [10] <-- sample bit 0
+ bst x1, USBMINUS ;1 [01]
+ bld shift, 0 ;1 [02]
+ push cnt ;2 [03+04]
+ ldi cnt, USB_BUFSIZE ;1 [05]
+ push x4 ;2 [06+07] tx loop
+ rjmp rxLoop ;2 [08]
+;----------------------------------------------------------------------------
+; Receiver loop (numbers in brackets are cycles within byte after instr)
+;----------------------------------------------------------------------------
+unstuff0: ;- [07] (branch taken)
+ andi x3, ~0x01 ;1 [08]
+ mov x1, x2 ;1 [09] x2 contains last sampled (stuffed) bit
+ in x2, USBIN ;1 [00] [10] <-- sample bit 1 again
+ andi x2, USBMASK ;1 [01]
+ breq se0Hop ;1 [02] SE0 check for bit 1
+ ori shift, 0x01 ;1 [03] 0b00000001
+ nop ;1 [04]
+ rjmp didUnstuff0 ;2 [05]
+;-----------------------------------------------------
+unstuff1: ;- [05] (branch taken)
+ mov x2, x1 ;1 [06] x1 contains last sampled (stuffed) bit
+ andi x3, ~0x02 ;1 [07]
+ ori shift, 0x02 ;1 [08] 0b00000010
+ nop ;1 [09]
+ in x1, USBIN ;1 [00] [10] <-- sample bit 2 again
+ andi x1, USBMASK ;1 [01]
+ breq se0Hop ;1 [02] SE0 check for bit 2
+ rjmp didUnstuff1 ;2 [03]
+;-----------------------------------------------------
+unstuff2: ;- [05] (branch taken)
+ andi x3, ~0x04 ;1 [06]
+ ori shift, 0x04 ;1 [07] 0b00000100
+ mov x1, x2 ;1 [08] x2 contains last sampled (stuffed) bit
+ nop ;1 [09]
+ in x2, USBIN ;1 [00] [10] <-- sample bit 3
+ andi x2, USBMASK ;1 [01]
+ breq se0Hop ;1 [02] SE0 check for bit 3
+ rjmp didUnstuff2 ;2 [03]
+;-----------------------------------------------------
+unstuff3: ;- [00] [10] (branch taken)
+ in x2, USBIN ;1 [01] [11] <-- sample stuffed bit 3 one cycle too late
+ andi x2, USBMASK ;1 [02]
+ breq se0Hop ;1 [03] SE0 check for stuffed bit 3
+ andi x3, ~0x08 ;1 [04]
+ ori shift, 0x08 ;1 [05] 0b00001000
+ rjmp didUnstuff3 ;2 [06]
+;----------------------------------------------------------------------------
+; extra jobs done during bit interval:
+;
+; bit 0: store, clear [SE0 is unreliable here due to bit dribbling in hubs],
+; overflow check, jump to the head of rxLoop
+; bit 1: SE0 check
+; bit 2: SE0 check, recovery from delay [bit 0 tasks took too long]
+; bit 3: SE0 check, recovery from delay [bit 0 tasks took too long]
+; bit 4: SE0 check, none
+; bit 5: SE0 check, none
+; bit 6: SE0 check, none
+; bit 7: SE0 check, reconstruct: x3 is 0 at bit locations we changed, 1 at others
+;----------------------------------------------------------------------------
+rxLoop: ;- [09]
+ in x2, USBIN ;1 [00] [10] <-- sample bit 1 (or possibly bit 0 stuffed)
+ andi x2, USBMASK ;1 [01]
+ brne SkipSe0Hop ;1 [02]
+se0Hop: ;- [02]
+ rjmp se0 ;2 [03] SE0 check for bit 1
+SkipSe0Hop: ;- [03]
+ ser x3 ;1 [04]
+ andi shift, 0xf9 ;1 [05] 0b11111001
+ breq unstuff0 ;1 [06]
+didUnstuff0: ;- [06]
+ eor x1, x2 ;1 [07]
+ bst x1, USBMINUS ;1 [08]
+ bld shift, 1 ;1 [09]
+ in x1, USBIN ;1 [00] [10] <-- sample bit 2 (or possibly bit 1 stuffed)
+ andi x1, USBMASK ;1 [01]
+ breq se0Hop ;1 [02] SE0 check for bit 2
+ andi shift, 0xf3 ;1 [03] 0b11110011
+ breq unstuff1 ;1 [04] do remaining work for bit 1
+didUnstuff1: ;- [04]
+ eor x2, x1 ;1 [05]
+ bst x2, USBMINUS ;1 [06]
+ bld shift, 2 ;1 [07]
+ nop2 ;2 [08+09]
+ in x2, USBIN ;1 [00] [10] <-- sample bit 3 (or possibly bit 2 stuffed)
+ andi x2, USBMASK ;1 [01]
+ breq se0Hop ;1 [02] SE0 check for bit 3
+ andi shift, 0xe7 ;1 [03] 0b11100111
+ breq unstuff2 ;1 [04]
+didUnstuff2: ;- [04]
+ eor x1, x2 ;1 [05]
+ bst x1, USBMINUS ;1 [06]
+ bld shift, 3 ;1 [07]
+didUnstuff3: ;- [07]
+ andi shift, 0xcf ;1 [08] 0b11001111
+ breq unstuff3 ;1 [09]
+ in x1, USBIN ;1 [00] [10] <-- sample bit 4
+ andi x1, USBMASK ;1 [01]
+ breq se0Hop ;1 [02] SE0 check for bit 4
+ eor x2, x1 ;1 [03]
+ bst x2, USBMINUS ;1 [04]
+ bld shift, 4 ;1 [05]
+didUnstuff4: ;- [05]
+ andi shift, 0x9f ;1 [06] 0b10011111
+ breq unstuff4 ;1 [07]
+ nop2 ;2 [08+09]
+ in x2, USBIN ;1 [00] [10] <-- sample bit 5
+ andi x2, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for bit 5
+ eor x1, x2 ;1 [03]
+ bst x1, USBMINUS ;1 [04]
+ bld shift, 5 ;1 [05]
+didUnstuff5: ;- [05]
+ andi shift, 0x3f ;1 [06] 0b00111111
+ breq unstuff5 ;1 [07]
+ nop2 ;2 [08+09]
+ in x1, USBIN ;1 [00] [10] <-- sample bit 6
+ andi x1, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for bit 6
+ eor x2, x1 ;1 [03]
+ bst x2, USBMINUS ;1 [04]
+ bld shift, 6 ;1 [05]
+didUnstuff6: ;- [05]
+ cpi shift, 0x02 ;1 [06] 0b00000010
+ brlo unstuff6 ;1 [07]
+ nop2 ;2 [08+09]
+ in x2, USBIN ;1 [00] [10] <-- sample bit 7
+ andi x2, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for bit 7
+ eor x1, x2 ;1 [03]
+ bst x1, USBMINUS ;1 [04]
+ bld shift, 7 ;1 [05]
+didUnstuff7: ;- [05]
+ cpi shift, 0x04 ;1 [06] 0b00000100
+ brlo unstuff7 ;1 [07]
+ eor x3, shift ;1 [08] reconstruct: x3 is 0 at bit locations we changed, 1 at others
+ nop ;1 [09]
+ in x1, USBIN ;1 [00] [10] <-- sample bit 0
+ st y+, x3 ;2 [01+02] store data
+ eor x2, x1 ;1 [03]
+ bst x2, USBMINUS ;1 [04]
+ bld shift, 0 ;1 [05]
+ subi cnt, 1 ;1 [06]
+ brcs overflow ;1 [07]
+ rjmp rxLoop ;2 [08]
+;-----------------------------------------------------
+unstuff4: ;- [08]
+ andi x3, ~0x10 ;1 [09]
+ in x1, USBIN ;1 [00] [10] <-- sample stuffed bit 4
+ andi x1, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for stuffed bit 4
+ ori shift, 0x10 ;1 [03]
+ rjmp didUnstuff4 ;2 [04]
+;-----------------------------------------------------
+unstuff5: ;- [08]
+ ori shift, 0x20 ;1 [09]
+ in x2, USBIN ;1 [00] [10] <-- sample stuffed bit 5
+ andi x2, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for stuffed bit 5
+ andi x3, ~0x20 ;1 [03]
+ rjmp didUnstuff5 ;2 [04]
+;-----------------------------------------------------
+unstuff6: ;- [08]
+ andi x3, ~0x40 ;1 [09]
+ in x1, USBIN ;1 [00] [10] <-- sample stuffed bit 6
+ andi x1, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for stuffed bit 6
+ ori shift, 0x40 ;1 [03]
+ rjmp didUnstuff6 ;2 [04]
+;-----------------------------------------------------
+unstuff7: ;- [08]
+ andi x3, ~0x80 ;1 [09]
+ in x2, USBIN ;1 [00] [10] <-- sample stuffed bit 7
+ andi x2, USBMASK ;1 [01]
+ breq se0 ;1 [02] SE0 check for stuffed bit 7
+ ori shift, 0x80 ;1 [03]
+ rjmp didUnstuff7 ;2 [04]
+
+macro POP_STANDARD ; 16 cycles
+ pop x4
+ pop cnt
+ pop bitcnt
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop YH
+ endm
+macro POP_RETI ; 5 cycles
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+#include "asmcommon.inc"
+
+;---------------------------------------------------------------------------
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1)
+; K = (D+ = 1), (D- = 0)
+; Spec allows 7.5 bit times from EOP to SOP for replies
+;---------------------------------------------------------------------------
+bitstuffN: ;- [04]
+ eor x1, x4 ;1 [05]
+ clr x2 ;1 [06]
+ nop ;1 [07]
+ rjmp didStuffN ;1 [08]
+;---------------------------------------------------------------------------
+bitstuff6: ;- [04]
+ eor x1, x4 ;1 [05]
+ clr x2 ;1 [06]
+ rjmp didStuff6 ;1 [07]
+;---------------------------------------------------------------------------
+bitstuff7: ;- [02]
+ eor x1, x4 ;1 [03]
+ clr x2 ;1 [06]
+ nop ;1 [05]
+ rjmp didStuff7 ;1 [06]
+;---------------------------------------------------------------------------
+sendNakAndReti: ;- [-19]
+ ldi x3, USBPID_NAK ;1 [-18]
+ rjmp sendX3AndReti ;1 [-17]
+;---------------------------------------------------------------------------
+sendAckAndReti: ;- [-17]
+ ldi cnt, USBPID_ACK ;1 [-16]
+sendCntAndReti: ;- [-16]
+ mov x3, cnt ;1 [-15]
+sendX3AndReti: ;- [-15]
+ ldi YL, 20 ;1 [-14] x3==r20 address is 20
+ ldi YH, 0 ;1 [-13]
+ ldi cnt, 2 ;1 [-12]
+; rjmp usbSendAndReti fallthrough
+;---------------------------------------------------------------------------
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte [range 2 ... 12]
+;uses: x1...x4, btcnt, shift, cnt, Y
+;Numbers in brackets are time since first bit of sync pattern is sent
+;We need not to match the transfer rate exactly because the spec demands
+;only 1.5% precision anyway.
+usbSendAndReti: ;- [-13] 13 cycles until SOP
+ in x2, USBDDR ;1 [-12]
+ ori x2, USBMASK ;1 [-11]
+ sbi USBOUT, USBMINUS ;2 [-09-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ in x1, USBOUT ;1 [-08] port mirror for tx loop
+ out USBDDR, x2 ;1 [-07] <- acquire bus
+ ; need not init x2 (bitstuff history) because sync starts with 0
+ ldi x4, USBMASK ;1 [-06] exor mask
+ ldi shift, 0x80 ;1 [-05] sync byte is first byte sent
+ ldi bitcnt, 6 ;1 [-04]
+txBitLoop: ;- [-04] [06]
+ sbrs shift, 0 ;1 [-03] [07]
+ eor x1, x4 ;1 [-02] [08]
+ ror shift ;1 [-01] [09]
+didStuffN: ;- [09]
+ out USBOUT, x1 ;1 [00] [10] <-- out N
+ ror x2 ;1 [01]
+ cpi x2, 0xfc ;1 [02]
+ brcc bitstuffN ;1 [03]
+ dec bitcnt ;1 [04]
+ brne txBitLoop ;1 [05]
+ sbrs shift, 0 ;1 [06]
+ eor x1, x4 ;1 [07]
+ ror shift ;1 [08]
+didStuff6: ;- [08]
+ nop ;1 [09]
+ out USBOUT, x1 ;1 [00] [10] <-- out 6
+ ror x2 ;1 [01]
+ cpi x2, 0xfc ;1 [02]
+ brcc bitstuff6 ;1 [03]
+ sbrs shift, 0 ;1 [04]
+ eor x1, x4 ;1 [05]
+ ror shift ;1 [06]
+ ror x2 ;1 [07]
+didStuff7: ;- [07]
+ ldi bitcnt, 6 ;1 [08]
+ cpi x2, 0xfc ;1 [09]
+ out USBOUT, x1 ;1 [00] [10] <-- out 7
+ brcc bitstuff7 ;1 [01]
+ ld shift, y+ ;2 [02+03]
+ dec cnt ;1 [04]
+ brne txBitLoop ;1 [05]
+makeSE0:
+ cbr x1, USBMASK ;1 [06] prepare SE0 [spec says EOP may be 19 to 23 cycles]
+ lds x2, usbNewDeviceAddr;2 [07+08]
+ lsl x2 ;1 [09] we compare with left shifted address
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ out USBOUT, x1 ;1 [00] [10] <-- out SE0-- from now 2 bits==20 cycl. until bus idle
+ subi YL, 20 + 2 ;1 [01] Only assign address on data packets, not ACK/NAK in x3
+ sbci YH, 0 ;1 [02]
+ breq skipAddrAssign ;1 [03]
+ sts usbDeviceAddr, x2 ;2 [04+05] if not skipped: SE0 is one cycle longer
+;----------------------------------------------------------------------------
+;end of usbDeviceAddress transfer
+skipAddrAssign: ;- [03/04]
+ ldi x2, 1<<USB_INTR_PENDING_BIT ;1 [05] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;1 [06]
+ ori x1, USBIDLE ;1 [07]
+ in x2, USBDDR ;1 [08]
+ cbr x2, USBMASK ;1 [09] set both pins to input
+ mov x3, x1 ;1 [10]
+ cbr x3, USBMASK ;1 [11] configure no pullup on both pins
+ ldi x4, 3 ;1 [12]
+se0Delay: ;- [12] [15]
+ dec x4 ;1 [13] [16]
+ brne se0Delay ;1 [14] [17]
+ nop2 ;2 [18+19]
+ out USBOUT, x1 ;1 [20] <--out J (idle) -- end of SE0 (EOP sig.)
+ out USBDDR, x2 ;1 [21] <--release bus now
+ out USBOUT, x3 ;1 [22] <--ensure no pull-up resistors are active
+ rjmp doReturn ;1 [23]
+;---------------------------------------------------------------------------
--- /dev/null
+/* Name: usbdrvasm16.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2007-06-15
+ * Tabsize: 4
+ * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 16 MHz version of the asssembler part of the USB driver. It
+requires a 16 MHz crystal (not a ceramic resonator and not a calibrated RC
+oscillator).
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+*/
+
+;max stack usage: [ret(2), YL, SREG, YH, bitcnt, shift, x1, x2, x3, x4, cnt] = 12 bytes
+;nominal frequency: 16 MHz -> 10.6666666 cycles per bit, 85.333333333 cycles per byte
+; Numbers in brackets are clocks counted from center of last sync bit
+; when instruction starts
+
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG YH, [sofError], bitcnt, shift, x1, x2, x3, x4, cnt
+ push YL ;[-25] push only what is necessary to sync with edge ASAP
+ in YL, SREG ;[-23]
+ push YL ;[-22]
+ push YH ;[-20]
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of < 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS ;[-15]
+ rjmp foundK ;[-14]
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+foundK: ;[-12]
+;{3, 5} after falling D- edge, average delay: 4 cycles [we want 5 for center sampling]
+;we have 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push bitcnt ;[-12]
+; [---] ;[-11]
+ lds YL, usbInputBufOffset;[-10]
+; [---] ;[-9]
+ clr YH ;[-8]
+ subi YL, lo8(-(usbRxBuf));[-7] [rx loop init]
+ sbci YH, hi8(-(usbRxBuf));[-6] [rx loop init]
+ push shift ;[-5]
+; [---] ;[-4]
+ ldi bitcnt, 0x55 ;[-3] [rx loop init]
+ sbis USBIN, USBMINUS ;[-2] we want two bits K (sample 2 cycles too early)
+ rjmp haveTwoBitsK ;[-1]
+ pop shift ;[0] undo the push from before
+ pop bitcnt ;[2] undo the push from before
+ rjmp waitForK ;[4] this was not the end of sync, retry
+; The entire loop from waitForK until rjmp waitForK above must not exceed two
+; bit times (= 21 cycles).
+
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+haveTwoBitsK:
+ push x1 ;[1]
+ push x2 ;[3]
+ push x3 ;[5]
+ ldi shift, 0 ;[7]
+ ldi x3, 1<<4 ;[8] [rx loop init] first sample is inverse bit, compensate that
+ push x4 ;[9] == leap
+
+ in x1, USBIN ;[11] <-- sample bit 0
+ andi x1, USBMASK ;[12]
+ bst x1, USBMINUS ;[13]
+ bld shift, 7 ;[14]
+ push cnt ;[15]
+ ldi leap, 0 ;[17] [rx loop init]
+ ldi cnt, USB_BUFSIZE;[18] [rx loop init]
+ rjmp rxbit1 ;[19] arrives at [21]
+
+;----------------------------------------------------------------------------
+; Receiver loop (numbers in brackets are cycles within byte after instr)
+;----------------------------------------------------------------------------
+
+; duration of unstuffing code should be 10.66666667 cycles. We adjust "leap"
+; accordingly to approximate this value in the long run.
+
+unstuff6:
+ andi x2, USBMASK ;[03]
+ ori x3, 1<<6 ;[04] will not be shifted any more
+ andi shift, ~0x80;[05]
+ mov x1, x2 ;[06] sampled bit 7 is actually re-sampled bit 6
+ subi leap, -1 ;[07] total duration = 11 bits -> subtract 1/3
+ rjmp didUnstuff6 ;[08]
+
+unstuff7:
+ ori x3, 1<<7 ;[09] will not be shifted any more
+ in x2, USBIN ;[00] [10] re-sample bit 7
+ andi x2, USBMASK ;[01]
+ andi shift, ~0x80;[02]
+ subi leap, 2 ;[03] total duration = 10 bits -> add 1/3
+ rjmp didUnstuff7 ;[04]
+
+unstuffEven:
+ ori x3, 1<<6 ;[09] will be shifted right 6 times for bit 0
+ in x1, USBIN ;[00] [10]
+ andi shift, ~0x80;[01]
+ andi x1, USBMASK ;[02]
+ breq se0 ;[03]
+ subi leap, -1 ;[04] total duration = 11 bits -> subtract 1/3
+ nop2 ;[05]
+ rjmp didUnstuffE ;[06]
+
+unstuffOdd:
+ ori x3, 1<<5 ;[09] will be shifted right 4 times for bit 1
+ in x2, USBIN ;[00] [10]
+ andi shift, ~0x80;[01]
+ andi x2, USBMASK ;[02]
+ breq se0 ;[03]
+ subi leap, -1 ;[04] total duration = 11 bits -> subtract 1/3
+ nop2 ;[05]
+ rjmp didUnstuffO ;[06]
+
+rxByteLoop:
+ andi x1, USBMASK ;[03]
+ eor x2, x1 ;[04]
+ subi leap, 1 ;[05]
+ brpl skipLeap ;[06]
+ subi leap, -3 ;1 one leap cycle every 3rd byte -> 85 + 1/3 cycles per byte
+ nop ;1
+skipLeap:
+ subi x2, 1 ;[08]
+ ror shift ;[09]
+didUnstuff6:
+ cpi shift, 0xfc ;[10]
+ in x2, USBIN ;[00] [11] <-- sample bit 7
+ brcc unstuff6 ;[01]
+ andi x2, USBMASK ;[02]
+ eor x1, x2 ;[03]
+ subi x1, 1 ;[04]
+ ror shift ;[05]
+didUnstuff7:
+ cpi shift, 0xfc ;[06]
+ brcc unstuff7 ;[07]
+ eor x3, shift ;[08] reconstruct: x3 is 1 at bit locations we changed, 0 at others
+ st y+, x3 ;[09] store data
+rxBitLoop:
+ in x1, USBIN ;[00] [11] <-- sample bit 0/2/4
+ andi x1, USBMASK ;[01]
+ eor x2, x1 ;[02]
+ andi x3, 0x3f ;[03] topmost two bits reserved for 6 and 7
+ subi x2, 1 ;[04]
+ ror shift ;[05]
+ cpi shift, 0xfc ;[06]
+ brcc unstuffEven ;[07]
+didUnstuffE:
+ lsr x3 ;[08]
+ lsr x3 ;[09]
+rxbit1:
+ in x2, USBIN ;[00] [10] <-- sample bit 1/3/5
+ andi x2, USBMASK ;[01]
+ breq se0 ;[02]
+ eor x1, x2 ;[03]
+ subi x1, 1 ;[04]
+ ror shift ;[05]
+ cpi shift, 0xfc ;[06]
+ brcc unstuffOdd ;[07]
+didUnstuffO:
+ subi bitcnt, 0xab;[08] == addi 0x55, 0x55 = 0x100/3
+ brcs rxBitLoop ;[09]
+
+ subi cnt, 1 ;[10]
+ in x1, USBIN ;[00] [11] <-- sample bit 6
+ brcc rxByteLoop ;[01]
+ rjmp overflow
+
+macro POP_STANDARD ; 14 cycles
+ pop cnt
+ pop x4
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop bitcnt
+ endm
+macro POP_RETI ; 7 cycles
+ pop YH
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+#include "asmcommon.inc"
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1)
+; K = (D+ = 1), (D- = 0)
+; Spec allows 7.5 bit times from EOP to SOP for replies
+
+bitstuffN:
+ eor x1, x4 ;[5]
+ ldi x2, 0 ;[6]
+ nop2 ;[7]
+ nop ;[9]
+ out USBOUT, x1 ;[10] <-- out
+ rjmp didStuffN ;[0]
+
+bitstuff6:
+ eor x1, x4 ;[5]
+ ldi x2, 0 ;[6] Carry is zero due to brcc
+ rol shift ;[7] compensate for ror shift at branch destination
+ rjmp didStuff6 ;[8]
+
+bitstuff7:
+ ldi x2, 0 ;[2] Carry is zero due to brcc
+ rjmp didStuff7 ;[3]
+
+
+sendNakAndReti:
+ ldi x3, USBPID_NAK ;[-18]
+ rjmp sendX3AndReti ;[-17]
+sendAckAndReti:
+ ldi cnt, USBPID_ACK ;[-17]
+sendCntAndReti:
+ mov x3, cnt ;[-16]
+sendX3AndReti:
+ ldi YL, 20 ;[-15] x3==r20 address is 20
+ ldi YH, 0 ;[-14]
+ ldi cnt, 2 ;[-13]
+; rjmp usbSendAndReti fallthrough
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte [range 2 ... 12]
+;uses: x1...x4, btcnt, shift, cnt, Y
+;Numbers in brackets are time since first bit of sync pattern is sent
+;We don't match the transfer rate exactly (don't insert leap cycles every third
+;byte) because the spec demands only 1.5% precision anyway.
+usbSendAndReti: ; 12 cycles until SOP
+ in x2, USBDDR ;[-12]
+ ori x2, USBMASK ;[-11]
+ sbi USBOUT, USBMINUS;[-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ in x1, USBOUT ;[-8] port mirror for tx loop
+ out USBDDR, x2 ;[-7] <- acquire bus
+; need not init x2 (bitstuff history) because sync starts with 0
+ ldi x4, USBMASK ;[-6] exor mask
+ ldi shift, 0x80 ;[-5] sync byte is first byte sent
+txByteLoop:
+ ldi bitcnt, 0x35 ;[-4] [6] binary 0011 0101
+txBitLoop:
+ sbrs shift, 0 ;[-3] [7]
+ eor x1, x4 ;[-2] [8]
+ out USBOUT, x1 ;[-1] [9] <-- out N
+ ror shift ;[0] [10]
+ ror x2 ;[1]
+didStuffN:
+ cpi x2, 0xfc ;[2]
+ brcc bitstuffN ;[3]
+ lsr bitcnt ;[4]
+ brcc txBitLoop ;[5]
+ brne txBitLoop ;[6]
+
+ sbrs shift, 0 ;[7]
+ eor x1, x4 ;[8]
+didStuff6:
+ out USBOUT, x1 ;[-1] [9] <-- out 6
+ ror shift ;[0] [10]
+ ror x2 ;[1]
+ cpi x2, 0xfc ;[2]
+ brcc bitstuff6 ;[3]
+ ror shift ;[4]
+didStuff7:
+ ror x2 ;[5]
+ sbrs x2, 7 ;[6]
+ eor x1, x4 ;[7]
+ nop ;[8]
+ cpi x2, 0xfc ;[9]
+ out USBOUT, x1 ;[-1][10] <-- out 7
+ brcc bitstuff7 ;[0] [11]
+ ld shift, y+ ;[1]
+ dec cnt ;[3]
+ brne txByteLoop ;[4]
+;make SE0:
+ cbr x1, USBMASK ;[5] prepare SE0 [spec says EOP may be 21 to 25 cycles]
+ lds x2, usbNewDeviceAddr;[6]
+ lsl x2 ;[8] we compare with left shifted address
+ subi YL, 20 + 2 ;[9] Only assign address on data packets, not ACK/NAK in x3
+ sbci YH, 0 ;[10]
+ out USBOUT, x1 ;[11] <-- out SE0 -- from now 2 bits = 22 cycles until bus idle
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ breq skipAddrAssign ;[0]
+ sts usbDeviceAddr, x2; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[2] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[3]
+ ori x1, USBIDLE ;[4]
+ in x2, USBDDR ;[5]
+ cbr x2, USBMASK ;[6] set both pins to input
+ mov x3, x1 ;[7]
+ cbr x3, USBMASK ;[8] configure no pullup on both pins
+ ldi x4, 4 ;[9]
+se0Delay:
+ dec x4 ;[10] [13] [16] [19]
+ brne se0Delay ;[11] [14] [17] [20]
+ out USBOUT, x1 ;[21] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[22] <-- release bus now
+ out USBOUT, x3 ;[23] <-- ensure no pull-up resistors are active
+ rjmp doReturn
--- /dev/null
+/* Name: usbdrvasm165.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2007-04-22
+ * Tabsize: 4
+ * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 16.5 MHz version of the USB driver. It is intended for the
+ATTiny45 and similar controllers running on 16.5 MHz internal RC oscillator.
+This version contains a phase locked loop in the receiver routine to cope with
+slight clock rate deviations of up to +/- 1%.
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+*/
+
+;Software-receiver engine. Strict timing! Don't change unless you can preserve timing!
+;interrupt response time: 4 cycles + insn running = 7 max if interrupts always enabled
+;max allowable interrupt latency: 59 cycles -> max 52 cycles interrupt disable
+;max stack usage: [ret(2), r0, SREG, YL, YH, shift, x1, x2, x3, x4, cnt] = 12 bytes
+;nominal frequency: 16.5 MHz -> 11 cycles per bit
+; 16.3125 MHz < F_CPU < 16.6875 MHz (+/- 1.1%)
+; Numbers in brackets are clocks counted from center of last sync bit
+; when instruction starts
+
+
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG [sofError], r0, YH, shift, x1, x2, x3, x4, cnt
+ push YL ;[-23] push only what is necessary to sync with edge ASAP
+ in YL, SREG ;[-21]
+ push YL ;[-20]
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of < 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS ;[-15]
+ rjmp foundK ;[-14]
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+foundK: ;[-12]
+;{3, 5} after falling D- edge, average delay: 4 cycles [we want 5 for center sampling]
+;we have 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push r0 ;[-12]
+; [---] ;[-11]
+ push YH ;[-10]
+; [---] ;[-9]
+ lds YL, usbInputBufOffset;[-8]
+; [---] ;[-7]
+ clr YH ;[-6]
+ subi YL, lo8(-(usbRxBuf));[-5] [rx loop init]
+ sbci YH, hi8(-(usbRxBuf));[-4] [rx loop init]
+ mov r0, x2 ;[-3] [rx loop init]
+ sbis USBIN, USBMINUS ;[-2] we want two bits K (sample 2 cycles too early)
+ rjmp haveTwoBitsK ;[-1]
+ pop YH ;[0] undo the pushes from before
+ pop r0 ;[2]
+ rjmp waitForK ;[4] this was not the end of sync, retry
+; The entire loop from waitForK until rjmp waitForK above must not exceed two
+; bit times (= 22 cycles).
+
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+haveTwoBitsK: ;[1]
+ push shift ;[1]
+ push x1 ;[3]
+ push x2 ;[5]
+ push x3 ;[7]
+ ldi shift, 0xff ;[9] [rx loop init]
+ ori x3, 0xff ;[10] [rx loop init] == ser x3, clear zero flag
+
+ in x1, USBIN ;[11] <-- sample bit 0
+ bst x1, USBMINUS ;[12]
+ bld shift, 0 ;[13]
+ push x4 ;[14] == phase
+; [---] ;[15]
+ push cnt ;[16]
+; [---] ;[17]
+ ldi phase, 0 ;[18] [rx loop init]
+ ldi cnt, USB_BUFSIZE;[19] [rx loop init]
+ rjmp rxbit1 ;[20]
+; [---] ;[21]
+
+;----------------------------------------------------------------------------
+; Receiver loop (numbers in brackets are cycles within byte after instr)
+;----------------------------------------------------------------------------
+/*
+byte oriented operations done during loop:
+bit 0: store data
+bit 1: SE0 check
+bit 2: overflow check
+bit 3: catch up
+bit 4: rjmp to achieve conditional jump range
+bit 5: PLL
+bit 6: catch up
+bit 7: jump, fixup bitstuff
+; 87 [+ 2] cycles
+------------------------------------------------------------------
+*/
+continueWithBit5:
+ in x2, USBIN ;[055] <-- bit 5
+ eor r0, x2 ;[056]
+ or phase, r0 ;[057]
+ sbrc phase, USBMINUS ;[058]
+ lpm ;[059] optional nop3; modifies r0
+ in phase, USBIN ;[060] <-- phase
+ eor x1, x2 ;[061]
+ bst x1, USBMINUS ;[062]
+ bld shift, 5 ;[063]
+ andi shift, 0x3f ;[064]
+ in x1, USBIN ;[065] <-- bit 6
+ breq unstuff5 ;[066] *** unstuff escape
+ eor phase, x1 ;[067]
+ eor x2, x1 ;[068]
+ bst x2, USBMINUS ;[069]
+ bld shift, 6 ;[070]
+didUnstuff6: ;[ ]
+ in r0, USBIN ;[071] <-- phase
+ cpi shift, 0x02 ;[072]
+ brlo unstuff6 ;[073] *** unstuff escape
+didUnstuff5: ;[ ]
+ nop2 ;[074]
+; [---] ;[075]
+ in x2, USBIN ;[076] <-- bit 7
+ eor x1, x2 ;[077]
+ bst x1, USBMINUS ;[078]
+ bld shift, 7 ;[079]
+didUnstuff7: ;[ ]
+ eor r0, x2 ;[080]
+ or phase, r0 ;[081]
+ in r0, USBIN ;[082] <-- phase
+ cpi shift, 0x04 ;[083]
+ brsh rxLoop ;[084]
+; [---] ;[085]
+unstuff7: ;[ ]
+ andi x3, ~0x80 ;[085]
+ ori shift, 0x80 ;[086]
+ in x2, USBIN ;[087] <-- sample stuffed bit 7
+ nop ;[088]
+ rjmp didUnstuff7 ;[089]
+; [---] ;[090]
+ ;[080]
+
+unstuff5: ;[067]
+ eor phase, x1 ;[068]
+ andi x3, ~0x20 ;[069]
+ ori shift, 0x20 ;[070]
+ in r0, USBIN ;[071] <-- phase
+ mov x2, x1 ;[072]
+ nop ;[073]
+ nop2 ;[074]
+; [---] ;[075]
+ in x1, USBIN ;[076] <-- bit 6
+ eor r0, x1 ;[077]
+ or phase, r0 ;[078]
+ eor x2, x1 ;[079]
+ bst x2, USBMINUS ;[080]
+ bld shift, 6 ;[081] no need to check bitstuffing, we just had one
+ in r0, USBIN ;[082] <-- phase
+ rjmp didUnstuff5 ;[083]
+; [---] ;[084]
+ ;[074]
+
+unstuff6: ;[074]
+ andi x3, ~0x40 ;[075]
+ in x1, USBIN ;[076] <-- bit 6 again
+ ori shift, 0x40 ;[077]
+ nop2 ;[078]
+; [---] ;[079]
+ rjmp didUnstuff6 ;[080]
+; [---] ;[081]
+ ;[071]
+
+unstuff0: ;[013]
+ eor r0, x2 ;[014]
+ or phase, r0 ;[015]
+ andi x2, USBMASK ;[016] check for SE0
+ in r0, USBIN ;[017] <-- phase
+ breq didUnstuff0 ;[018] direct jump to se0 would be too long
+ andi x3, ~0x01 ;[019]
+ ori shift, 0x01 ;[020]
+ mov x1, x2 ;[021] mov existing sample
+ in x2, USBIN ;[022] <-- bit 1 again
+ rjmp didUnstuff0 ;[023]
+; [---] ;[024]
+ ;[014]
+
+unstuff1: ;[024]
+ eor r0, x1 ;[025]
+ or phase, r0 ;[026]
+ andi x3, ~0x02 ;[027]
+ in r0, USBIN ;[028] <-- phase
+ ori shift, 0x02 ;[029]
+ mov x2, x1 ;[030]
+ rjmp didUnstuff1 ;[031]
+; [---] ;[032]
+ ;[022]
+
+unstuff2: ;[035]
+ eor r0, x2 ;[036]
+ or phase, r0 ;[037]
+ andi x3, ~0x04 ;[038]
+ in r0, USBIN ;[039] <-- phase
+ ori shift, 0x04 ;[040]
+ mov x1, x2 ;[041]
+ rjmp didUnstuff2 ;[042]
+; [---] ;[043]
+ ;[033]
+
+unstuff3: ;[043]
+ in x2, USBIN ;[044] <-- bit 3 again
+ eor r0, x2 ;[045]
+ or phase, r0 ;[046]
+ andi x3, ~0x08 ;[047]
+ ori shift, 0x08 ;[048]
+ nop ;[049]
+ in r0, USBIN ;[050] <-- phase
+ rjmp didUnstuff3 ;[051]
+; [---] ;[052]
+ ;[042]
+
+unstuff4: ;[053]
+ andi x3, ~0x10 ;[054]
+ in x1, USBIN ;[055] <-- bit 4 again
+ ori shift, 0x10 ;[056]
+ rjmp didUnstuff4 ;[057]
+; [---] ;[058]
+ ;[048]
+
+rxLoop: ;[085]
+ eor x3, shift ;[086] reconstruct: x3 is 0 at bit locations we changed, 1 at others
+ in x1, USBIN ;[000] <-- bit 0
+ st y+, x3 ;[001]
+; [---] ;[002]
+ eor r0, x1 ;[003]
+ or phase, r0 ;[004]
+ eor x2, x1 ;[005]
+ in r0, USBIN ;[006] <-- phase
+ ser x3 ;[007]
+ bst x2, USBMINUS ;[008]
+ bld shift, 0 ;[009]
+ andi shift, 0xf9 ;[010]
+rxbit1: ;[ ]
+ in x2, USBIN ;[011] <-- bit 1
+ breq unstuff0 ;[012] *** unstuff escape
+ andi x2, USBMASK ;[013] SE0 check for bit 1
+didUnstuff0: ;[ ] Z only set if we detected SE0 in bitstuff
+ breq se0 ;[014]
+ eor r0, x2 ;[015]
+ or phase, r0 ;[016]
+ in r0, USBIN ;[017] <-- phase
+ eor x1, x2 ;[018]
+ bst x1, USBMINUS ;[019]
+ bld shift, 1 ;[020]
+ andi shift, 0xf3 ;[021]
+didUnstuff1: ;[ ]
+ in x1, USBIN ;[022] <-- bit 2
+ breq unstuff1 ;[023] *** unstuff escape
+ eor r0, x1 ;[024]
+ or phase, r0 ;[025]
+ subi cnt, 1 ;[026] overflow check
+ brcs overflow ;[027]
+ in r0, USBIN ;[028] <-- phase
+ eor x2, x1 ;[029]
+ bst x2, USBMINUS ;[030]
+ bld shift, 2 ;[031]
+ andi shift, 0xe7 ;[032]
+didUnstuff2: ;[ ]
+ in x2, USBIN ;[033] <-- bit 3
+ breq unstuff2 ;[034] *** unstuff escape
+ eor r0, x2 ;[035]
+ or phase, r0 ;[036]
+ eor x1, x2 ;[037]
+ bst x1, USBMINUS ;[038]
+ in r0, USBIN ;[039] <-- phase
+ bld shift, 3 ;[040]
+ andi shift, 0xcf ;[041]
+didUnstuff3: ;[ ]
+ breq unstuff3 ;[042] *** unstuff escape
+ nop ;[043]
+ in x1, USBIN ;[044] <-- bit 4
+ eor x2, x1 ;[045]
+ bst x2, USBMINUS ;[046]
+ bld shift, 4 ;[047]
+didUnstuff4: ;[ ]
+ eor r0, x1 ;[048]
+ or phase, r0 ;[049]
+ in r0, USBIN ;[050] <-- phase
+ andi shift, 0x9f ;[051]
+ breq unstuff4 ;[052] *** unstuff escape
+ rjmp continueWithBit5;[053]
+; [---] ;[054]
+
+macro POP_STANDARD ; 16 cycles
+ pop cnt
+ pop x4
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop YH
+ pop r0
+ endm
+macro POP_RETI ; 5 cycles
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+#include "asmcommon.inc"
+
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1)
+; K = (D+ = 1), (D- = 0)
+; Spec allows 7.5 bit times from EOP to SOP for replies
+
+bitstuff7:
+ eor x1, x4 ;[4]
+ ldi x2, 0 ;[5]
+ nop2 ;[6] C is zero (brcc)
+ rjmp didStuff7 ;[8]
+
+bitstuffN:
+ eor x1, x4 ;[5]
+ ldi x2, 0 ;[6]
+ lpm ;[7] 3 cycle NOP, modifies r0
+ out USBOUT, x1 ;[10] <-- out
+ rjmp didStuffN ;[0]
+
+#define bitStatus x3
+
+sendNakAndReti:
+ ldi cnt, USBPID_NAK ;[-19]
+ rjmp sendCntAndReti ;[-18]
+sendAckAndReti:
+ ldi cnt, USBPID_ACK ;[-17]
+sendCntAndReti:
+ mov r0, cnt ;[-16]
+ ldi YL, 0 ;[-15] R0 address is 0
+ ldi YH, 0 ;[-14]
+ ldi cnt, 2 ;[-13]
+; rjmp usbSendAndReti fallthrough
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte [range 2 ... 12]
+;uses: x1...x4, shift, cnt, Y
+;Numbers in brackets are time since first bit of sync pattern is sent
+usbSendAndReti: ; 12 cycles until SOP
+ in x2, USBDDR ;[-12]
+ ori x2, USBMASK ;[-11]
+ sbi USBOUT, USBMINUS;[-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ in x1, USBOUT ;[-8] port mirror for tx loop
+ out USBDDR, x2 ;[-7] <- acquire bus
+; need not init x2 (bitstuff history) because sync starts with 0
+ ldi x4, USBMASK ;[-6] exor mask
+ ldi shift, 0x80 ;[-5] sync byte is first byte sent
+ ldi bitStatus, 0xff ;[-4] init bit loop counter, works for up to 12 bytes
+byteloop:
+bitloop:
+ sbrs shift, 0 ;[8] [-3]
+ eor x1, x4 ;[9] [-2]
+ out USBOUT, x1 ;[10] [-1] <-- out
+ ror shift ;[0]
+ ror x2 ;[1]
+didStuffN:
+ cpi x2, 0xfc ;[2]
+ brcc bitstuffN ;[3]
+ nop ;[4]
+ subi bitStatus, 37 ;[5] 256 / 7 ~=~ 37
+ brcc bitloop ;[6] when we leave the loop, bitStatus has almost the initial value
+ sbrs shift, 0 ;[7]
+ eor x1, x4 ;[8]
+ ror shift ;[9]
+didStuff7:
+ out USBOUT, x1 ;[10] <-- out
+ ror x2 ;[0]
+ cpi x2, 0xfc ;[1]
+ brcc bitstuff7 ;[2]
+ ld shift, y+ ;[3]
+ dec cnt ;[5]
+ brne byteloop ;[6]
+;make SE0:
+ cbr x1, USBMASK ;[7] prepare SE0 [spec says EOP may be 21 to 25 cycles]
+ lds x2, usbNewDeviceAddr;[8]
+ lsl x2 ;[10] we compare with left shifted address
+ out USBOUT, x1 ;[11] <-- out SE0 -- from now 2 bits = 22 cycles until bus idle
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ subi YL, 2 ;[0] Only assign address on data packets, not ACK/NAK in r0
+ sbci YH, 0 ;[1]
+ breq skipAddrAssign ;[2]
+ sts usbDeviceAddr, x2; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[4] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[5]
+ ori x1, USBIDLE ;[6]
+ in x2, USBDDR ;[7]
+ cbr x2, USBMASK ;[8] set both pins to input
+ mov x3, x1 ;[9]
+ cbr x3, USBMASK ;[10] configure no pullup on both pins
+ ldi x4, 4 ;[11]
+se0Delay:
+ dec x4 ;[12] [15] [18] [21]
+ brne se0Delay ;[13] [16] [19] [22]
+ out USBOUT, x1 ;[23] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[24] <-- release bus now
+ out USBOUT, x3 ;[25] <-- ensure no pull-up resistors are active
+ rjmp doReturn
+
--- /dev/null
+/* Name: usbdrvasm18.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Lukas Schrittwieser (based on 20 MHz usbdrvasm20.inc by Jeroen Benschop)
+ * Creation Date: 2009-01-20
+ * Tabsize: 4
+ * Copyright: (c) 2008 by Lukas Schrittwieser and OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 18 MHz version of the asssembler part of the USB driver. It
+requires a 18 MHz crystal (not a ceramic resonator and not a calibrated RC
+oscillator).
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+*/
+
+
+;max stack usage: [ret(2), YL, SREG, YH, [sofError], bitcnt(x5), shift, x1, x2, x3, x4, cnt, ZL, ZH] = 14 bytes
+;nominal frequency: 18 MHz -> 12 cycles per bit
+; Numbers in brackets are clocks counted from center of last sync bit
+; when instruction starts
+;register use in receive loop to receive the data bytes:
+; shift assembles the byte currently being received
+; x1 holds the D+ and D- line state
+; x2 holds the previous line state
+; cnt holds the number of bytes left in the receive buffer
+; x3 holds the higher crc byte (see algorithm below)
+; x4 is used as temporary register for the crc algorithm
+; x5 is used for unstuffing: when unstuffing the last received bit is inverted in shift (to prevent further
+; unstuffing calls. In the same time the corresponding bit in x5 is cleared to mark the bit as beening iverted
+; zl lower crc value and crc table index
+; zh used for crc table accesses
+
+;--------------------------------------------------------------------------------------------------------------
+; CRC mods:
+; table driven crc checker, Z points to table in prog space
+; ZL is the lower crc byte, x3 is the higher crc byte
+; x4 is used as temp register to store different results
+; the initialization of the crc register is not 0xFFFF but 0xFE54. This is because during the receipt of the
+; first data byte an virtual zero data byte is added to the crc register, this results in the correct initial
+; value of 0xFFFF at beginning of the second data byte before the first data byte is added to the crc.
+; The magic number 0xFE54 results form the crc table: At tabH[0x54] = 0xFF = crcH (required) and
+; tabL[0x54] = 0x01 -> crcL = 0x01 xor 0xFE = 0xFF
+; bitcnt is renamed to x5 and is used for unstuffing purposes, the unstuffing works like in the 12MHz version
+;--------------------------------------------------------------------------------------------------------------
+; CRC algorithm:
+; The crc register is formed by x3 (higher byte) and ZL (lower byte). The algorithm uses a 'reversed' form
+; i.e. that it takes the least significant bit first and shifts to the right. So in fact the highest order
+; bit seen from the polynomial devision point of view is the lsb of ZL. (If this sounds strange to you i
+; propose a research on CRC :-) )
+; Each data byte received is xored to ZL, the lower crc byte. This byte now builds the crc
+; table index. Next the new high byte is loaded from the table and stored in x4 until we have space in x3
+; (its destination).
+; Afterwards the lower table is loaded from the table and stored in ZL (the old index is overwritten as
+; we don't need it anymore. In fact this is a right shift by 8 bits.) Now the old crc high value is xored
+; to ZL, this is the second shift of the old crc value. Now x4 (the temp reg) is moved to x3 and the crc
+; calculation is done.
+; Prior to the first byte the two CRC register have to be initialized to 0xFFFF (as defined in usb spec)
+; however the crc engine also runs during the receipt of the first byte, therefore x3 and zl are initialized
+; to a magic number which results in a crc value of 0xFFFF after the first complete byte.
+;
+; This algorithm is split into the extra cycles of the different bits:
+; bit7: XOR the received byte to ZL
+; bit5: load the new high byte to x4
+; bit6: load the lower xor byte from the table, xor zl and x3, store result in zl (=the new crc low value)
+; move x4 (the new high byte) to x3, the crc value is ready
+;
+
+
+macro POP_STANDARD ; 18 cycles
+ pop ZH
+ pop ZL
+ pop cnt
+ pop x5
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop x4
+ endm
+macro POP_RETI ; 7 cycles
+ pop YH
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+macro CRC_CLEANUP_AND_CHECK
+ ; the last byte has already been xored with the lower crc byte, we have to do the table lookup and xor
+ ; x3 is the higher crc byte, zl the lower one
+ ldi ZH, hi8(usbCrcTableHigh);[+1] get the new high byte from the table
+ lpm x2, Z ;[+2][+3][+4]
+ ldi ZH, hi8(usbCrcTableLow);[+5] get the new low xor byte from the table
+ lpm ZL, Z ;[+6][+7][+8]
+ eor ZL, x3 ;[+7] xor the old high byte with the value from the table, x2:ZL now holds the crc value
+ cpi ZL, 0x01 ;[+8] if the crc is ok we have a fixed remainder value of 0xb001 in x2:ZL (see usb spec)
+ brne ignorePacket ;[+9] detected a crc fault -> paket is ignored and retransmitted by the host
+ cpi x2, 0xb0 ;[+10]
+ brne ignorePacket ;[+11] detected a crc fault -> paket is ignored and retransmitted by the host
+ endm
+
+
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG, YH, [sofError], x4, shift, x1, x2, x3, x5, cnt, ZL, ZH
+ push YL ;[-28] push only what is necessary to sync with edge ASAP
+ in YL, SREG ;[-26]
+ push YL ;[-25]
+ push YH ;[-23]
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of < 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS ;[-17]
+ rjmp foundK ;[-16]
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+foundK: ;[-15]
+;{3, 5} after falling D- edge, average delay: 4 cycles
+;bit0 should be at 30 (2.5 bits) for center sampling. Currently at 4 so 26 cylces till bit 0 sample
+;use 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push x4 ;[-14]
+; [---] ;[-13]
+ lds YL, usbInputBufOffset;[-12] used to toggle the two usb receive buffers
+; [---] ;[-11]
+ clr YH ;[-10]
+ subi YL, lo8(-(usbRxBuf));[-9] [rx loop init]
+ sbci YH, hi8(-(usbRxBuf));[-8] [rx loop init]
+ push shift ;[-7]
+; [---] ;[-6]
+ ldi shift, 0x80 ;[-5] the last bit is the end of byte marker for the pid receiver loop
+ clc ;[-4] the carry has to be clear for receipt of pid bit 0
+ sbis USBIN, USBMINUS ;[-3] we want two bits K (sample 3 cycles too early)
+ rjmp haveTwoBitsK ;[-2]
+ pop shift ;[-1] undo the push from before
+ pop x4 ;[1]
+ rjmp waitForK ;[3] this was not the end of sync, retry
+; The entire loop from waitForK until rjmp waitForK above must not exceed two
+; bit times (= 24 cycles).
+
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+haveTwoBitsK:
+ push x1 ;[0]
+ push x2 ;[2]
+ push x3 ;[4] crc high byte
+ ldi x2, 1<<USBPLUS ;[6] [rx loop init] current line state is K state. D+=="1", D-=="0"
+ push x5 ;[7]
+ push cnt ;[9]
+ ldi cnt, USB_BUFSIZE ;[11]
+
+
+;--------------------------------------------------------------------------------------------------------------
+; receives the pid byte
+; there is no real unstuffing algorithm implemented here as a stuffing bit is impossible in the pid byte.
+; That's because the last four bits of the byte are the inverted of the first four bits. If we detect a
+; unstuffing condition something went wrong and abort
+; shift has to be initialized to 0x80
+;--------------------------------------------------------------------------------------------------------------
+
+; pid bit 0 - used for even more register saving (we need the z pointer)
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] filter only D+ and D- bits
+ eor x2, x1 ;[2] generate inverted of actual bit
+ sbrc x2, USBMINUS ;[3] if the bit is set we received a zero
+ sec ;[4]
+ ror shift ;[5] we perform no unstuffing check here as this is the first bit
+ mov x2, x1 ;[6]
+ push ZL ;[7]
+ ;[8]
+ push ZH ;[9]
+ ;[10]
+ ldi x3, 0xFE ;[11] x3 is the high order crc value
+
+
+bitloopPid:
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] filter only D+ and D- bits
+ breq nse0 ;[2] both lines are low so handle se0
+ eor x2, x1 ;[3] generate inverted of actual bit
+ sbrc x2, USBMINUS ;[4] set the carry if we received a zero
+ sec ;[5]
+ ror shift ;[6]
+ ldi ZL, 0x54 ;[7] ZL is the low order crc value
+ ser x4 ;[8] the is no bit stuffing check here as the pid bit can't be stuffed. if so
+ ; some error occured. In this case the paket is discarded later on anyway.
+ mov x2, x1 ;[9] prepare for the next cycle
+ brcc bitloopPid ;[10] while 0s drop out of shift we get the next bit
+ eor x4, shift ;[11] invert all bits in shift and store result in x4
+
+;--------------------------------------------------------------------------------------------------------------
+; receives data bytes and calculates the crc
+; the last USBIN state has to be in x2
+; this is only the first half, due to branch distanc limitations the second half of the loop is near the end
+; of this asm file
+;--------------------------------------------------------------------------------------------------------------
+
+rxDataStart:
+ in x1, USBIN ;[0] sample line state (note: a se0 check is not useful due to bit dribbling)
+ ser x5 ;[1] prepare the unstuff marker register
+ eor x2, x1 ;[2] generates the inverted of the actual bit
+ bst x2, USBMINUS ;[3] copy the bit from x2
+ bld shift, 0 ;[4] and store it in shift
+ mov x2, shift ;[5] make a copy of shift for unstuffing check
+ andi x2, 0xF9 ;[6] mask the last six bits, if we got six zeros (which are six ones in fact)
+ breq unstuff0 ;[7] then Z is set now and we branch to the unstuffing handler
+didunstuff0:
+ subi cnt, 1 ;[8] cannot use dec because it doesn't affect the carry flag
+ brcs nOverflow ;[9] Too many bytes received. Ignore packet
+ st Y+, x4 ;[10] store the last received byte
+ ;[11] st needs two cycles
+
+; bit1
+ in x2, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] check for se0 during bit 0
+ breq nse0 ;[2]
+ andi x2, USBMASK ;[3] check se0 during bit 1
+ breq nse0 ;[4]
+ eor x1, x2 ;[5]
+ bst x1, USBMINUS ;[6]
+ bld shift, 1 ;[7]
+ mov x1, shift ;[8]
+ andi x1, 0xF3 ;[9]
+ breq unstuff1 ;[10]
+didunstuff1:
+ nop ;[11]
+
+; bit2
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] check for se0 (as there is nothing else to do here
+ breq nOverflow ;[2]
+ eor x2, x1 ;[3] generates the inverted of the actual bit
+ bst x2, USBMINUS ;[4]
+ bld shift, 2 ;[5] store the bit
+ mov x2, shift ;[6]
+ andi x2, 0xE7 ;[7] if we have six zeros here (which means six 1 in the stream)
+ breq unstuff2 ;[8] the next bit is a stuffing bit
+didunstuff2:
+ nop2 ;[9]
+ ;[10]
+ nop ;[11]
+
+; bit3
+ in x2, USBIN ;[0] sample line state
+ andi x2, USBMASK ;[1] check for se0
+ breq nOverflow ;[2]
+ eor x1, x2 ;[3]
+ bst x1, USBMINUS ;[4]
+ bld shift, 3 ;[5]
+ mov x1, shift ;[6]
+ andi x1, 0xCF ;[7]
+ breq unstuff3 ;[8]
+didunstuff3:
+ nop ;[9]
+ rjmp rxDataBit4 ;[10]
+ ;[11]
+
+; the avr branch instructions allow an offset of +63 insturction only, so we need this
+; 'local copy' of se0
+nse0:
+ rjmp se0 ;[4]
+ ;[5]
+; the same same as for se0 is needed for overflow and StuffErr
+nOverflow:
+stuffErr:
+ rjmp overflow
+
+
+unstuff0: ;[8] this is the branch delay of breq unstuffX
+ andi x1, USBMASK ;[9] do an se0 check here (if the last crc byte ends with 5 one's we might end up here
+ breq didunstuff0 ;[10] event tough the message is complete -> jump back and store the byte
+ ori shift, 0x01 ;[11] invert the last received bit to prevent furhter unstuffing
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ andi x5, 0xFE ;[1] mark this bit as inverted (will be corrected before storing shift)
+ eor x1, x2 ;[2] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[3] mask the interesting bits
+ breq stuffErr ;[4] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[5] the next bit expects the last state to be in x1
+ rjmp didunstuff0 ;[6]
+ ;[7] jump delay of rjmp didunstuffX
+
+unstuff1: ;[11] this is the jump delay of breq unstuffX
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ ori shift, 0x02 ;[1] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0xFD ;[2] mark this bit as inverted (will be corrected before storing shift)
+ eor x2, x1 ;[3] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[4] mask the interesting bits
+ breq stuffErr ;[5] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[6] the next bit expects the last state to be in x2
+ nop2 ;[7]
+ ;[8]
+ rjmp didunstuff1 ;[9]
+ ;[10] jump delay of rjmp didunstuffX
+
+unstuff2: ;[9] this is the jump delay of breq unstuffX
+ ori shift, 0x04 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0xFB ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x1, x2 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[2] mask the interesting bits
+ breq stuffErr ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[4] the next bit expects the last state to be in x1
+ nop2 ;[5]
+ ;[6]
+ rjmp didunstuff2 ;[7]
+ ;[8] jump delay of rjmp didunstuffX
+
+unstuff3: ;[9] this is the jump delay of breq unstuffX
+ ori shift, 0x08 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0xF7 ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x2, x1 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[2] mask the interesting bits
+ breq stuffErr ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[4] the next bit expects the last state to be in x2
+ nop2 ;[5]
+ ;[6]
+ rjmp didunstuff3 ;[7]
+ ;[8] jump delay of rjmp didunstuffX
+
+
+
+; the include has to be here due to branch distance restirctions
+#define __USE_CRC__
+#include "asmcommon.inc"
+
+
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1)
+; K = (D+ = 1), (D- = 0)
+; Spec allows 7.5 bit times from EOP to SOP for replies
+; 7.5 bit times is 90 cycles. ...there is plenty of time
+
+
+sendNakAndReti:
+ ldi x3, USBPID_NAK ;[-18]
+ rjmp sendX3AndReti ;[-17]
+sendAckAndReti:
+ ldi cnt, USBPID_ACK ;[-17]
+sendCntAndReti:
+ mov x3, cnt ;[-16]
+sendX3AndReti:
+ ldi YL, 20 ;[-15] x3==r20 address is 20
+ ldi YH, 0 ;[-14]
+ ldi cnt, 2 ;[-13]
+; rjmp usbSendAndReti fallthrough
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte [range 2 ... 12]
+;uses: x1...x4, btcnt, shift, cnt, Y
+;Numbers in brackets are time since first bit of sync pattern is sent
+
+usbSendAndReti: ; 12 cycles until SOP
+ in x2, USBDDR ;[-12]
+ ori x2, USBMASK ;[-11]
+ sbi USBOUT, USBMINUS;[-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ in x1, USBOUT ;[-8] port mirror for tx loop
+ out USBDDR, x2 ;[-6] <- acquire bus
+ ldi x2, 0 ;[-6] init x2 (bitstuff history) because sync starts with 0
+ ldi x4, USBMASK ;[-5] exor mask
+ ldi shift, 0x80 ;[-4] sync byte is first byte sent
+txByteLoop:
+ ldi bitcnt, 0x40 ;[-3]=[9] binary 01000000
+txBitLoop: ; the loop sends the first 7 bits of the byte
+ sbrs shift, 0 ;[-2]=[10] if we have to send a 1 don't change the line state
+ eor x1, x4 ;[-1]=[11]
+ out USBOUT, x1 ;[0]
+ ror shift ;[1]
+ ror x2 ;[2] transfers the last sent bit to the stuffing history
+didStuffN:
+ nop ;[3]
+ nop ;[4]
+ cpi x2, 0xfc ;[5] if we sent six consecutive ones
+ brcc bitstuffN ;[6]
+ lsr bitcnt ;[7]
+ brne txBitLoop ;[8] restart the loop while the 1 is still in the bitcount
+
+; transmit bit 7
+ sbrs shift, 0 ;[9]
+ eor x1, x4 ;[10]
+didStuff7:
+ ror shift ;[11]
+ out USBOUT, x1 ;[0] transfer bit 7 to the pins
+ ror x2 ;[1] move the bit into the stuffing history
+ cpi x2, 0xfc ;[2]
+ brcc bitstuff7 ;[3]
+ ld shift, y+ ;[4] get next byte to transmit
+ dec cnt ;[5] decrement byte counter
+ brne txByteLoop ;[7] if we have more bytes start next one
+ ;[8] branch delay
+
+;make SE0:
+ cbr x1, USBMASK ;[8] prepare SE0 [spec says EOP may be 25 to 30 cycles]
+ lds x2, usbNewDeviceAddr;[9]
+ lsl x2 ;[11] we compare with left shifted address
+ out USBOUT, x1 ;[0] <-- out SE0 -- from now 2 bits = 24 cycles until bus idle
+ subi YL, 20 + 2 ;[1] Only assign address on data packets, not ACK/NAK in x3
+ sbci YH, 0 ;[2]
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ breq skipAddrAssign ;[3]
+ sts usbDeviceAddr, x2 ; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[5] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[6]
+ ori x1, USBIDLE ;[7]
+ in x2, USBDDR ;[8]
+ cbr x2, USBMASK ;[9] set both pins to input
+ mov x3, x1 ;[10]
+ cbr x3, USBMASK ;[11] configure no pullup on both pins
+ ldi x4, 4 ;[12]
+se0Delay:
+ dec x4 ;[13] [16] [19] [22]
+ brne se0Delay ;[14] [17] [20] [23]
+ out USBOUT, x1 ;[24] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[25] <-- release bus now
+ out USBOUT, x3 ;[26] <-- ensure no pull-up resistors are active
+ rjmp doReturn
+
+bitstuffN:
+ eor x1, x4 ;[8] generate a zero
+ ldi x2, 0 ;[9] reset the bit stuffing history
+ nop2 ;[10]
+ out USBOUT, x1 ;[0] <-- send the stuffing bit
+ rjmp didStuffN ;[1]
+
+bitstuff7:
+ eor x1, x4 ;[5]
+ ldi x2, 0 ;[6] reset bit stuffing history
+ clc ;[7] fill a zero into the shift register
+ rol shift ;[8] compensate for ror shift at branch destination
+ rjmp didStuff7 ;[9]
+ ;[10] jump delay
+
+;--------------------------------------------------------------------------------------------------------------
+; receives data bytes and calculates the crc
+; second half of the data byte receiver loop
+; most parts of the crc algorithm are here
+;--------------------------------------------------------------------------------------------------------------
+
+nOverflow2:
+ rjmp overflow
+
+rxDataBit4:
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] check for se0
+ breq nOverflow2 ;[2]
+ eor x2, x1 ;[3]
+ bst x2, USBMINUS ;[4]
+ bld shift, 4 ;[5]
+ mov x2, shift ;[6]
+ andi x2, 0x9F ;[7]
+ breq unstuff4 ;[8]
+didunstuff4:
+ nop2 ;[9][10]
+ nop ;[11]
+
+; bit5
+ in x2, USBIN ;[0] sample line state
+ ldi ZH, hi8(usbCrcTableHigh);[1] use the table for the higher byte
+ eor x1, x2 ;[2]
+ bst x1, USBMINUS ;[3]
+ bld shift, 5 ;[4]
+ mov x1, shift ;[5]
+ andi x1, 0x3F ;[6]
+ breq unstuff5 ;[7]
+didunstuff5:
+ lpm x4, Z ;[8] load the higher crc xor-byte and store it for later use
+ ;[9] lpm needs 3 cycles
+ ;[10]
+ ldi ZH, hi8(usbCrcTableLow);[11] load the lower crc xor byte adress
+
+; bit6
+ in x1, USBIN ;[0] sample line state
+ eor x2, x1 ;[1]
+ bst x2, USBMINUS ;[2]
+ bld shift, 6 ;[3]
+ mov x2, shift ;[4]
+ andi x2, 0x7E ;[5]
+ breq unstuff6 ;[6]
+didunstuff6:
+ lpm ZL, Z ;[7] load the lower xor crc byte
+ ;[8] lpm needs 3 cycles
+ ;[9]
+ eor ZL, x3 ;[10] xor the old high crc byte with the low xor-byte
+ mov x3, x4 ;[11] move the new high order crc value from temp to its destination
+
+; bit7
+ in x2, USBIN ;[0] sample line state
+ eor x1, x2 ;[1]
+ bst x1, USBMINUS ;[2]
+ bld shift, 7 ;[3] now shift holds the complete but inverted data byte
+ mov x1, shift ;[4]
+ andi x1, 0xFC ;[5]
+ breq unstuff7 ;[6]
+didunstuff7:
+ eor x5, shift ;[7] x5 marks all bits which have not been inverted by the unstuffing subs
+ mov x4, x5 ;[8] keep a copy of the data byte it will be stored during next bit0
+ eor ZL, x4 ;[9] feed the actual byte into the crc algorithm
+ rjmp rxDataStart ;[10] next byte
+ ;[11] during the reception of the next byte this one will be fed int the crc algorithm
+
+unstuff4: ;[9] this is the jump delay of rjmp unstuffX
+ ori shift, 0x10 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0xEF ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x1, x2 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[4] the next bit expects the last state to be in x1
+ nop2 ;[5]
+ ;[6]
+ rjmp didunstuff4 ;[7]
+ ;[8] jump delay of rjmp didunstuffX
+
+unstuff5: ;[8] this is the jump delay of rjmp unstuffX
+ nop ;[9]
+ ori shift, 0x20 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0xDF ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x2, x1 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[4] the next bit expects the last state to be in x2
+ nop ;[5]
+ rjmp didunstuff5 ;[6]
+ ;[7] jump delay of rjmp didunstuffX
+
+unstuff6: ;[7] this is the jump delay of rjmp unstuffX
+ nop2 ;[8]
+ ;[9]
+ ori shift, 0x40 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0xBF ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x1, x2 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[4] the next bit expects the last state to be in x1
+ rjmp didunstuff6 ;[5]
+ ;[6] jump delay of rjmp didunstuffX
+
+unstuff7: ;[7] this is the jump delay of rjmp unstuffX
+ nop ;[8]
+ nop ;[9]
+ ori shift, 0x80 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x5, 0x7F ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x2, x1 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[4] the next bit expects the last state to be in x2
+ rjmp didunstuff7 ;[5]
+ ;[6] jump delay of rjmp didunstuff7
+
+; local copy of the stuffErr desitnation for the second half of the receiver loop
+stuffErr2:
+ rjmp stuffErr
+
+;--------------------------------------------------------------------------------------------------------------
+; The crc table follows. It has to be aligned to enable a fast loading of the needed bytes.
+; There are two tables of 256 entries each, the low and the high byte table.
+; Table values were generated with the following C code:
+/*
+#include <stdio.h>
+int main (int argc, char **argv)
+{
+ int i, j;
+ for (i=0; i<512; i++){
+ unsigned short crc = i & 0xff;
+ for(j=0; j<8; j++) crc = (crc >> 1) ^ ((crc & 1) ? 0xa001 : 0);
+ if((i & 7) == 0) printf("\n.byte ");
+ printf("0x%02x, ", (i > 0xff ? (crc >> 8) : crc) & 0xff);
+ if(i == 255) printf("\n");
+ }
+ return 0;
+}
+
+// Use the following algorithm to compute CRC values:
+ushort computeCrc(uchar *msg, uchar msgLen)
+{
+ uchar i;
+ ushort crc = 0xffff;
+ for(i = 0; i < msgLen; i++)
+ crc = usbCrcTable16[lo8(crc) ^ msg[i]] ^ hi8(crc);
+ return crc;
+}
+*/
+
+.balign 256
+usbCrcTableLow:
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41
+.byte 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
+
+; .balign 256
+usbCrcTableHigh:
+.byte 0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2
+.byte 0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04
+.byte 0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E
+.byte 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, 0x08, 0xC8
+.byte 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A
+.byte 0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC
+.byte 0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6
+.byte 0xD2, 0x12, 0x13, 0xD3, 0x11, 0xD1, 0xD0, 0x10
+.byte 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32
+.byte 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4
+.byte 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE
+.byte 0xFA, 0x3A, 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38
+.byte 0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA
+.byte 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C
+.byte 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26
+.byte 0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0
+.byte 0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62
+.byte 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4
+.byte 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, 0x6E, 0xAE
+.byte 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68
+.byte 0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA
+.byte 0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C
+.byte 0xB4, 0x74, 0x75, 0xB5, 0x77, 0xB7, 0xB6, 0x76
+.byte 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0
+.byte 0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92
+.byte 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54
+.byte 0x9C, 0x5C, 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E
+.byte 0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98
+.byte 0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A
+.byte 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C
+.byte 0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86
+.byte 0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80, 0x40
+
--- /dev/null
+/* Name: usbdrvasm18.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Lukas Schrittwieser (based on 20 MHz usbdrvasm20.inc by Jeroen Benschop)
+ * Creation Date: 2009-01-20
+ * Tabsize: 4
+ * Copyright: (c) 2008 by Lukas Schrittwieser and OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 18 MHz version of the asssembler part of the USB driver. It
+requires a 18 MHz crystal (not a ceramic resonator and not a calibrated RC
+oscillator).
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+
+Note: This version is smaller than usbdrvasm18-crc.inc because it saves the CRC
+table. It's therefore suitable for boot loaders on boards @ 18 MHz. However, it
+is not as small as it could be, because loops are unrolled in the same way as in
+usbdrvasm18-crc.inc. There is room for optimization.
+*/
+
+
+;max stack usage: [ret(2), YL, SREG, YH, [sofError], bitcnt(x5), shift, x1, x2, x3, x4, cnt, ZL, ZH] = 14 bytes
+;nominal frequency: 18 MHz -> 12 cycles per bit
+; Numbers in brackets are clocks counted from center of last sync bit
+; when instruction starts
+;register use in receive loop to receive the data bytes:
+; shift assembles the byte currently being received
+; x1 holds the D+ and D- line state
+; x2 holds the previous line state
+; cnt holds the number of bytes left in the receive buffer
+; x4 is used as temporary register
+; x3 is used for unstuffing: when unstuffing the last received bit is inverted in shift (to prevent further
+; unstuffing calls. In the same time the corresponding bit in x3 is cleared to mark the bit as beening iverted
+; zl lower crc value and crc table index
+; zh used for crc table accesses
+
+
+
+macro POP_STANDARD ; 18 cycles
+ pop cnt
+ pop x5
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop x4
+ endm
+macro POP_RETI ; 7 cycles
+ pop YH
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+;macro CRC_CLEANUP_AND_CHECK
+; ; the last byte has already been xored with the lower crc byte, we have to do the table lookup and xor
+; ; x3 is the higher crc byte, zl the lower one
+; ldi ZH, hi8(usbCrcTableHigh);[+1] get the new high byte from the table
+; lpm x2, Z ;[+2][+3][+4]
+; ldi ZH, hi8(usbCrcTableLow);[+5] get the new low xor byte from the table
+; lpm ZL, Z ;[+6][+7][+8]
+; eor ZL, x3 ;[+7] xor the old high byte with the value from the table, x2:ZL now holds the crc value
+; cpi ZL, 0x01 ;[+8] if the crc is ok we have a fixed remainder value of 0xb001 in x2:ZL (see usb spec)
+; brne ignorePacket ;[+9] detected a crc fault -> paket is ignored and retransmitted by the host
+; cpi x2, 0xb0 ;[+10]
+; brne ignorePacket ;[+11] detected a crc fault -> paket is ignored and retransmitted by the host
+; endm
+
+
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG, YH, [sofError], x4, shift, x1, x2, x3, x5, cnt, ZL, ZH
+ push YL ;[-28] push only what is necessary to sync with edge ASAP
+ in YL, SREG ;[-26]
+ push YL ;[-25]
+ push YH ;[-23]
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of < 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS ;[-17]
+ rjmp foundK ;[-16]
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+foundK: ;[-15]
+;{3, 5} after falling D- edge, average delay: 4 cycles
+;bit0 should be at 30 (2.5 bits) for center sampling. Currently at 4 so 26 cylces till bit 0 sample
+;use 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push x4 ;[-14]
+; [---] ;[-13]
+ lds YL, usbInputBufOffset;[-12] used to toggle the two usb receive buffers
+; [---] ;[-11]
+ clr YH ;[-10]
+ subi YL, lo8(-(usbRxBuf));[-9] [rx loop init]
+ sbci YH, hi8(-(usbRxBuf));[-8] [rx loop init]
+ push shift ;[-7]
+; [---] ;[-6]
+ ldi shift, 0x80 ;[-5] the last bit is the end of byte marker for the pid receiver loop
+ clc ;[-4] the carry has to be clear for receipt of pid bit 0
+ sbis USBIN, USBMINUS ;[-3] we want two bits K (sample 3 cycles too early)
+ rjmp haveTwoBitsK ;[-2]
+ pop shift ;[-1] undo the push from before
+ pop x4 ;[1]
+ rjmp waitForK ;[3] this was not the end of sync, retry
+; The entire loop from waitForK until rjmp waitForK above must not exceed two
+; bit times (= 24 cycles).
+
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+haveTwoBitsK:
+ push x1 ;[0]
+ push x2 ;[2]
+ push x3 ;[4]
+ ldi x2, 1<<USBPLUS ;[6] [rx loop init] current line state is K state. D+=="1", D-=="0"
+ push x5 ;[7] used by tx loop for bitcnt
+ push cnt ;[9]
+ ldi cnt, USB_BUFSIZE ;[11]
+
+
+;--------------------------------------------------------------------------------------------------------------
+; receives the pid byte
+; there is no real unstuffing algorithm implemented here as a stuffing bit is impossible in the pid byte.
+; That's because the last four bits of the byte are the inverted of the first four bits. If we detect a
+; unstuffing condition something went wrong and abort
+; shift has to be initialized to 0x80
+;--------------------------------------------------------------------------------------------------------------
+
+bitloopPid:
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] filter only D+ and D- bits
+ breq nse0 ;[2] both lines are low so handle se0
+ eor x2, x1 ;[3] generate inverted of actual bit
+ sbrc x2, USBMINUS ;[4] set the carry if we received a zero
+ sec ;[5]
+ ror shift ;[6]
+ nop ;[7] ZL is the low order crc value
+ ser x4 ;[8] the is no bit stuffing check here as the pid bit can't be stuffed. if so
+ ; some error occured. In this case the paket is discarded later on anyway.
+ mov x2, x1 ;[9] prepare for the next cycle
+ brcc bitloopPid ;[10] while 0s drop out of shift we get the next bit
+ eor x4, shift ;[11] invert all bits in shift and store result in x4
+
+;--------------------------------------------------------------------------------------------------------------
+; receives data bytes and calculates the crc
+; the last USBIN state has to be in x2
+; this is only the first half, due to branch distanc limitations the second half of the loop is near the end
+; of this asm file
+;--------------------------------------------------------------------------------------------------------------
+
+rxDataStart:
+ in x1, USBIN ;[0] sample line state (note: a se0 check is not useful due to bit dribbling)
+ ser x3 ;[1] prepare the unstuff marker register
+ eor x2, x1 ;[2] generates the inverted of the actual bit
+ bst x2, USBMINUS ;[3] copy the bit from x2
+ bld shift, 0 ;[4] and store it in shift
+ mov x2, shift ;[5] make a copy of shift for unstuffing check
+ andi x2, 0xF9 ;[6] mask the last six bits, if we got six zeros (which are six ones in fact)
+ breq unstuff0 ;[7] then Z is set now and we branch to the unstuffing handler
+didunstuff0:
+ subi cnt, 1 ;[8] cannot use dec because it doesn't affect the carry flag
+ brcs nOverflow ;[9] Too many bytes received. Ignore packet
+ st Y+, x4 ;[10] store the last received byte
+ ;[11] st needs two cycles
+
+; bit1
+ in x2, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] check for se0 during bit 0
+ breq nse0 ;[2]
+ andi x2, USBMASK ;[3] check se0 during bit 1
+ breq nse0 ;[4]
+ eor x1, x2 ;[5]
+ bst x1, USBMINUS ;[6]
+ bld shift, 1 ;[7]
+ mov x1, shift ;[8]
+ andi x1, 0xF3 ;[9]
+ breq unstuff1 ;[10]
+didunstuff1:
+ nop ;[11]
+
+; bit2
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] check for se0 (as there is nothing else to do here
+ breq nOverflow ;[2]
+ eor x2, x1 ;[3] generates the inverted of the actual bit
+ bst x2, USBMINUS ;[4]
+ bld shift, 2 ;[5] store the bit
+ mov x2, shift ;[6]
+ andi x2, 0xE7 ;[7] if we have six zeros here (which means six 1 in the stream)
+ breq unstuff2 ;[8] the next bit is a stuffing bit
+didunstuff2:
+ nop2 ;[9]
+ ;[10]
+ nop ;[11]
+
+; bit3
+ in x2, USBIN ;[0] sample line state
+ andi x2, USBMASK ;[1] check for se0
+ breq nOverflow ;[2]
+ eor x1, x2 ;[3]
+ bst x1, USBMINUS ;[4]
+ bld shift, 3 ;[5]
+ mov x1, shift ;[6]
+ andi x1, 0xCF ;[7]
+ breq unstuff3 ;[8]
+didunstuff3:
+ nop ;[9]
+ rjmp rxDataBit4 ;[10]
+ ;[11]
+
+; the avr branch instructions allow an offset of +63 insturction only, so we need this
+; 'local copy' of se0
+nse0:
+ rjmp se0 ;[4]
+ ;[5]
+; the same same as for se0 is needed for overflow and StuffErr
+nOverflow:
+stuffErr:
+ rjmp overflow
+
+
+unstuff0: ;[8] this is the branch delay of breq unstuffX
+ andi x1, USBMASK ;[9] do an se0 check here (if the last crc byte ends with 5 one's we might end up here
+ breq didunstuff0 ;[10] event tough the message is complete -> jump back and store the byte
+ ori shift, 0x01 ;[11] invert the last received bit to prevent furhter unstuffing
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ andi x3, 0xFE ;[1] mark this bit as inverted (will be corrected before storing shift)
+ eor x1, x2 ;[2] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[3] mask the interesting bits
+ breq stuffErr ;[4] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[5] the next bit expects the last state to be in x1
+ rjmp didunstuff0 ;[6]
+ ;[7] jump delay of rjmp didunstuffX
+
+unstuff1: ;[11] this is the jump delay of breq unstuffX
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ ori shift, 0x02 ;[1] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0xFD ;[2] mark this bit as inverted (will be corrected before storing shift)
+ eor x2, x1 ;[3] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[4] mask the interesting bits
+ breq stuffErr ;[5] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[6] the next bit expects the last state to be in x2
+ nop2 ;[7]
+ ;[8]
+ rjmp didunstuff1 ;[9]
+ ;[10] jump delay of rjmp didunstuffX
+
+unstuff2: ;[9] this is the jump delay of breq unstuffX
+ ori shift, 0x04 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0xFB ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x1, x2 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[2] mask the interesting bits
+ breq stuffErr ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[4] the next bit expects the last state to be in x1
+ nop2 ;[5]
+ ;[6]
+ rjmp didunstuff2 ;[7]
+ ;[8] jump delay of rjmp didunstuffX
+
+unstuff3: ;[9] this is the jump delay of breq unstuffX
+ ori shift, 0x08 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0xF7 ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x2, x1 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[2] mask the interesting bits
+ breq stuffErr ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[4] the next bit expects the last state to be in x2
+ nop2 ;[5]
+ ;[6]
+ rjmp didunstuff3 ;[7]
+ ;[8] jump delay of rjmp didunstuffX
+
+
+
+; the include has to be here due to branch distance restirctions
+#include "asmcommon.inc"
+
+
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1)
+; K = (D+ = 1), (D- = 0)
+; Spec allows 7.5 bit times from EOP to SOP for replies
+; 7.5 bit times is 90 cycles. ...there is plenty of time
+
+
+sendNakAndReti:
+ ldi x3, USBPID_NAK ;[-18]
+ rjmp sendX3AndReti ;[-17]
+sendAckAndReti:
+ ldi cnt, USBPID_ACK ;[-17]
+sendCntAndReti:
+ mov x3, cnt ;[-16]
+sendX3AndReti:
+ ldi YL, 20 ;[-15] x3==r20 address is 20
+ ldi YH, 0 ;[-14]
+ ldi cnt, 2 ;[-13]
+; rjmp usbSendAndReti fallthrough
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte [range 2 ... 12]
+;uses: x1...x4, btcnt, shift, cnt, Y
+;Numbers in brackets are time since first bit of sync pattern is sent
+
+usbSendAndReti: ; 12 cycles until SOP
+ in x2, USBDDR ;[-12]
+ ori x2, USBMASK ;[-11]
+ sbi USBOUT, USBMINUS;[-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ in x1, USBOUT ;[-8] port mirror for tx loop
+ out USBDDR, x2 ;[-6] <- acquire bus
+ ldi x2, 0 ;[-6] init x2 (bitstuff history) because sync starts with 0
+ ldi x4, USBMASK ;[-5] exor mask
+ ldi shift, 0x80 ;[-4] sync byte is first byte sent
+txByteLoop:
+ ldi bitcnt, 0x40 ;[-3]=[9] binary 01000000
+txBitLoop: ; the loop sends the first 7 bits of the byte
+ sbrs shift, 0 ;[-2]=[10] if we have to send a 1 don't change the line state
+ eor x1, x4 ;[-1]=[11]
+ out USBOUT, x1 ;[0]
+ ror shift ;[1]
+ ror x2 ;[2] transfers the last sent bit to the stuffing history
+didStuffN:
+ nop ;[3]
+ nop ;[4]
+ cpi x2, 0xfc ;[5] if we sent six consecutive ones
+ brcc bitstuffN ;[6]
+ lsr bitcnt ;[7]
+ brne txBitLoop ;[8] restart the loop while the 1 is still in the bitcount
+
+; transmit bit 7
+ sbrs shift, 0 ;[9]
+ eor x1, x4 ;[10]
+didStuff7:
+ ror shift ;[11]
+ out USBOUT, x1 ;[0] transfer bit 7 to the pins
+ ror x2 ;[1] move the bit into the stuffing history
+ cpi x2, 0xfc ;[2]
+ brcc bitstuff7 ;[3]
+ ld shift, y+ ;[4] get next byte to transmit
+ dec cnt ;[5] decrement byte counter
+ brne txByteLoop ;[7] if we have more bytes start next one
+ ;[8] branch delay
+
+;make SE0:
+ cbr x1, USBMASK ;[8] prepare SE0 [spec says EOP may be 25 to 30 cycles]
+ lds x2, usbNewDeviceAddr;[9]
+ lsl x2 ;[11] we compare with left shifted address
+ out USBOUT, x1 ;[0] <-- out SE0 -- from now 2 bits = 24 cycles until bus idle
+ subi YL, 20 + 2 ;[1] Only assign address on data packets, not ACK/NAK in x3
+ sbci YH, 0 ;[2]
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ breq skipAddrAssign ;[3]
+ sts usbDeviceAddr, x2 ; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[5] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[6]
+ ori x1, USBIDLE ;[7]
+ in x2, USBDDR ;[8]
+ cbr x2, USBMASK ;[9] set both pins to input
+ mov x3, x1 ;[10]
+ cbr x3, USBMASK ;[11] configure no pullup on both pins
+ ldi x4, 4 ;[12]
+se0Delay:
+ dec x4 ;[13] [16] [19] [22]
+ brne se0Delay ;[14] [17] [20] [23]
+ out USBOUT, x1 ;[24] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[25] <-- release bus now
+ out USBOUT, x3 ;[26] <-- ensure no pull-up resistors are active
+ rjmp doReturn
+
+bitstuffN:
+ eor x1, x4 ;[8] generate a zero
+ ldi x2, 0 ;[9] reset the bit stuffing history
+ nop2 ;[10]
+ out USBOUT, x1 ;[0] <-- send the stuffing bit
+ rjmp didStuffN ;[1]
+
+bitstuff7:
+ eor x1, x4 ;[5]
+ ldi x2, 0 ;[6] reset bit stuffing history
+ clc ;[7] fill a zero into the shift register
+ rol shift ;[8] compensate for ror shift at branch destination
+ rjmp didStuff7 ;[9]
+ ;[10] jump delay
+
+;--------------------------------------------------------------------------------------------------------------
+; receives data bytes and calculates the crc
+; second half of the data byte receiver loop
+; most parts of the crc algorithm are here
+;--------------------------------------------------------------------------------------------------------------
+
+nOverflow2:
+ rjmp overflow
+
+rxDataBit4:
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] check for se0
+ breq nOverflow2 ;[2]
+ eor x2, x1 ;[3]
+ bst x2, USBMINUS ;[4]
+ bld shift, 4 ;[5]
+ mov x2, shift ;[6]
+ andi x2, 0x9F ;[7]
+ breq unstuff4 ;[8]
+didunstuff4:
+ nop2 ;[9][10]
+ nop ;[11]
+
+; bit5
+ in x2, USBIN ;[0] sample line state
+ nop ;[1] use the table for the higher byte
+ eor x1, x2 ;[2]
+ bst x1, USBMINUS ;[3]
+ bld shift, 5 ;[4]
+ mov x1, shift ;[5]
+ andi x1, 0x3F ;[6]
+ breq unstuff5 ;[7]
+didunstuff5:
+ nop2 ;[8] load the higher crc xor-byte and store it for later use
+ ;[9] lpm needs 3 cycles
+ nop ;[10]
+ nop ;[11] load the lower crc xor byte adress
+
+; bit6
+ in x1, USBIN ;[0] sample line state
+ eor x2, x1 ;[1]
+ bst x2, USBMINUS ;[2]
+ bld shift, 6 ;[3]
+ mov x2, shift ;[4]
+ andi x2, 0x7E ;[5]
+ breq unstuff6 ;[6]
+didunstuff6:
+ nop2 ;[7] load the lower xor crc byte
+ ;[8] lpm needs 3 cycles
+ nop ;[9]
+ nop ;[10] xor the old high crc byte with the low xor-byte
+ nop ;[11] move the new high order crc value from temp to its destination
+
+; bit7
+ in x2, USBIN ;[0] sample line state
+ eor x1, x2 ;[1]
+ bst x1, USBMINUS ;[2]
+ bld shift, 7 ;[3] now shift holds the complete but inverted data byte
+ mov x1, shift ;[4]
+ andi x1, 0xFC ;[5]
+ breq unstuff7 ;[6]
+didunstuff7:
+ eor x3, shift ;[7] x3 marks all bits which have not been inverted by the unstuffing subs
+ mov x4, x3 ;[8] keep a copy of the data byte it will be stored during next bit0
+ nop ;[9] feed the actual byte into the crc algorithm
+ rjmp rxDataStart ;[10] next byte
+ ;[11] during the reception of the next byte this one will be fed int the crc algorithm
+
+unstuff4: ;[9] this is the jump delay of rjmp unstuffX
+ ori shift, 0x10 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0xEF ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x1, x2 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[4] the next bit expects the last state to be in x1
+ nop2 ;[5]
+ ;[6]
+ rjmp didunstuff4 ;[7]
+ ;[8] jump delay of rjmp didunstuffX
+
+unstuff5: ;[8] this is the jump delay of rjmp unstuffX
+ nop ;[9]
+ ori shift, 0x20 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0xDF ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x2, x1 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[4] the next bit expects the last state to be in x2
+ nop ;[5]
+ rjmp didunstuff5 ;[6]
+ ;[7] jump delay of rjmp didunstuffX
+
+unstuff6: ;[7] this is the jump delay of rjmp unstuffX
+ nop2 ;[8]
+ ;[9]
+ ori shift, 0x40 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0xBF ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x2, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x1, x2 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x1, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x1, x2 ;[4] the next bit expects the last state to be in x1
+ rjmp didunstuff6 ;[5]
+ ;[6] jump delay of rjmp didunstuffX
+
+unstuff7: ;[7] this is the jump delay of rjmp unstuffX
+ nop ;[8]
+ nop ;[9]
+ ori shift, 0x80 ;[10] invert the last received bit to prevent furhter unstuffing
+ andi x3, 0x7F ;[11] mark this bit as inverted (will be corrected before storing shift)
+ in x1, USBIN ;[0] we have some free cycles so we could check for bit stuffing errors
+ eor x2, x1 ;[1] x1 and x2 have to be different because the stuff bit is always a zero
+ andi x2, USBMASK ;[2] mask the interesting bits
+ breq stuffErr2 ;[3] if the stuff bit is a 1-bit something went wrong
+ mov x2, x1 ;[4] the next bit expects the last state to be in x2
+ rjmp didunstuff7 ;[5]
+ ;[6] jump delay of rjmp didunstuff7
+
+; local copy of the stuffErr desitnation for the second half of the receiver loop
+stuffErr2:
+ rjmp stuffErr
--- /dev/null
+/* Name: usbdrvasm20.inc
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Jeroen Benschop
+ * Based on usbdrvasm16.inc from Christian Starkjohann
+ * Creation Date: 2008-03-05
+ * Tabsize: 4
+ * Copyright: (c) 2008 by Jeroen Benschop and OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/* Do not link this file! Link usbdrvasm.S instead, which includes the
+ * appropriate implementation!
+ */
+
+/*
+General Description:
+This file is the 20 MHz version of the asssembler part of the USB driver. It
+requires a 20 MHz crystal (not a ceramic resonator and not a calibrated RC
+oscillator).
+
+See usbdrv.h for a description of the entire driver.
+
+Since almost all of this code is timing critical, don't change unless you
+really know what you are doing! Many parts require not only a maximum number
+of CPU cycles, but even an exact number of cycles!
+*/
+
+#define leap2 x3
+#ifdef __IAR_SYSTEMS_ASM__
+#define nextInst $+2
+#else
+#define nextInst .+0
+#endif
+
+;max stack usage: [ret(2), YL, SREG, YH, bitcnt, shift, x1, x2, x3, x4, cnt] = 12 bytes
+;nominal frequency: 20 MHz -> 13.333333 cycles per bit, 106.666667 cycles per byte
+; Numbers in brackets are clocks counted from center of last sync bit
+; when instruction starts
+;register use in receive loop:
+; shift assembles the byte currently being received
+; x1 holds the D+ and D- line state
+; x2 holds the previous line state
+; x4 (leap) is used to add a leap cycle once every three bytes received
+; X3 (leap2) is used to add a leap cycle once every three stuff bits received
+; bitcnt is used to determine when a stuff bit is due
+; cnt holds the number of bytes left in the receive buffer
+
+USB_INTR_VECTOR:
+;order of registers pushed: YL, SREG YH, [sofError], bitcnt, shift, x1, x2, x3, x4, cnt
+ push YL ;[-28] push only what is necessary to sync with edge ASAP
+ in YL, SREG ;[-26]
+ push YL ;[-25]
+ push YH ;[-23]
+;----------------------------------------------------------------------------
+; Synchronize with sync pattern:
+;----------------------------------------------------------------------------
+;sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K]
+;sync up with J to K edge during sync pattern -- use fastest possible loops
+;The first part waits at most 1 bit long since we must be in sync pattern.
+;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to
+;waitForJ, ensure that this prerequisite is met.
+waitForJ:
+ inc YL
+ sbis USBIN, USBMINUS
+ brne waitForJ ; just make sure we have ANY timeout
+waitForK:
+;The following code results in a sampling window of < 1/4 bit which meets the spec.
+ sbis USBIN, USBMINUS ;[-19]
+ rjmp foundK ;[-18]
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+ sbis USBIN, USBMINUS
+ rjmp foundK
+#if USB_COUNT_SOF
+ lds YL, usbSofCount
+ inc YL
+ sts usbSofCount, YL
+#endif /* USB_COUNT_SOF */
+#ifdef USB_SOF_HOOK
+ USB_SOF_HOOK
+#endif
+ rjmp sofError
+foundK: ;[-16]
+;{3, 5} after falling D- edge, average delay: 4 cycles
+;bit0 should be at 34 for center sampling. Currently at 4 so 30 cylces till bit 0 sample
+;use 1 bit time for setup purposes, then sample again. Numbers in brackets
+;are cycles from center of first sync (double K) bit after the instruction
+ push bitcnt ;[-16]
+; [---] ;[-15]
+ lds YL, usbInputBufOffset;[-14]
+; [---] ;[-13]
+ clr YH ;[-12]
+ subi YL, lo8(-(usbRxBuf));[-11] [rx loop init]
+ sbci YH, hi8(-(usbRxBuf));[-10] [rx loop init]
+ push shift ;[-9]
+; [---] ;[-8]
+ ldi shift,0x40 ;[-7] set msb to "1" so processing bit7 can be detected
+ nop2 ;[-6]
+; [---] ;[-5]
+ ldi bitcnt, 5 ;[-4] [rx loop init]
+ sbis USBIN, USBMINUS ;[-3] we want two bits K (sample 3 cycles too early)
+ rjmp haveTwoBitsK ;[-2]
+ pop shift ;[-1] undo the push from before
+ pop bitcnt ;[1]
+ rjmp waitForK ;[3] this was not the end of sync, retry
+; The entire loop from waitForK until rjmp waitForK above must not exceed two
+; bit times (= 27 cycles).
+
+;----------------------------------------------------------------------------
+; push more registers and initialize values while we sample the first bits:
+;----------------------------------------------------------------------------
+haveTwoBitsK:
+ push x1 ;[0]
+ push x2 ;[2]
+ push x3 ;[4] (leap2)
+ ldi leap2, 0x55 ;[6] add leap cycle on 2nd,5th,8th,... stuff bit
+ push x4 ;[7] == leap
+ ldi leap, 0x55 ;[9] skip leap cycle on 2nd,5th,8th,... byte received
+ push cnt ;[10]
+ ldi cnt, USB_BUFSIZE ;[12] [rx loop init]
+ ldi x2, 1<<USBPLUS ;[13] current line state is K state. D+=="1", D-=="0"
+bit0:
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] filter only D+ and D- bits
+ rjmp handleBit ;[2] make bit0 14 cycles long
+
+;----------------------------------------------------------------------------
+; Process bit7. However, bit 6 still may need unstuffing.
+;----------------------------------------------------------------------------
+
+b6checkUnstuff:
+ dec bitcnt ;[9]
+ breq unstuff6 ;[10]
+bit7:
+ subi cnt, 1 ;[11] cannot use dec becaus it does not affect the carry flag
+ brcs overflow ;[12] Too many bytes received. Ignore packet
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] filter only D+ and D- bits
+ cpse x1, x2 ;[2] when previous line state equals current line state, handle "1"
+ rjmp b7handle0 ;[3] when line state differs, handle "0"
+ sec ;[4]
+ ror shift ;[5] shift "1" into the data
+ st y+, shift ;[6] store the data into the buffer
+ ldi shift, 0x40 ;[7] reset data for receiving the next byte
+ subi leap, 0x55 ;[9] trick to introduce a leap cycle every 3 bytes
+ brcc nextInst ;[10 or 11] it will fail after 85 bytes. However low speed can only receive 11
+ dec bitcnt ;[11 or 12]
+ brne bit0 ;[12 or 13]
+ ldi x1, 1 ;[13 or 14] unstuffing bit 7
+ in bitcnt, USBIN ;[0] sample stuff bit
+ rjmp unstuff ;[1]
+
+b7handle0:
+ mov x2,x1 ;[5] Set x2 to current line state
+ ldi bitcnt, 6 ;[6]
+ lsr shift ;[7] shift "0" into the data
+ st y+, shift ;[8] store data into the buffer
+ ldi shift, 0x40 ;[10] reset data for receiving the next byte
+ subi leap, 0x55 ;[11] trick to introduce a leap cycle every 3 bytes
+ brcs bit0 ;[12] it will fail after 85 bytes. However low speed can only receive 11
+ rjmp bit0 ;[13]
+
+
+;----------------------------------------------------------------------------
+; Handle unstuff
+; x1==0xFF indicate unstuffing bit6
+;----------------------------------------------------------------------------
+
+unstuff6:
+ ldi x1,0xFF ;[12] indicate unstuffing bit 6
+ in bitcnt, USBIN ;[0] sample stuff bit
+ nop ;[1] fix timing
+unstuff: ;b0-5 b6 b7
+ mov x2,bitcnt ;[3] [2] [3] Set x2 to match line state
+ subi leap2, 0x55 ;[4] [3] [4] delay loop
+ brcs nextInst ;[5] [4] [5] add one cycle every three stuff bits
+ sbci leap2,0 ;[6] [5] [6]
+ ldi bitcnt,6 ;[7] [6] [7] reset bit stuff counter
+ andi x2, USBMASK ;[8] [7] [8] only keep D+ and D-
+ cpi x1,0 ;[9] [8] [9]
+ brmi bit7 ;[10] [9] [10] finished unstuffing bit6 When x1<0
+ breq bitloop ;[11] --- [11] finished unstuffing bit0-5 when x1=0
+ nop ;--- --- [12]
+ in x1, USBIN ;--- --- [0] sample line state for bit0
+ andi x1, USBMASK ;--- --- [1] filter only D+ and D- bits
+ rjmp handleBit ;--- --- [2] make bit0 14 cycles long
+
+;----------------------------------------------------------------------------
+; Receiver loop (numbers in brackets are cycles within byte after instr)
+;----------------------------------------------------------------------------
+bitloop:
+ in x1, USBIN ;[0] sample line state
+ andi x1, USBMASK ;[1] filter only D+ and D- bits
+ breq se0 ;[2] both lines are low so handle se0
+handleBit:
+ cpse x1, x2 ;[3] when previous line state equals current line state, handle "1"
+ rjmp handle0 ;[4] when line state differs, handle "0"
+ sec ;[5]
+ ror shift ;[6] shift "1" into the data
+ brcs b6checkUnstuff ;[7] When after shift C is set, next bit is bit7
+ nop2 ;[8]
+ dec bitcnt ;[10]
+ brne bitloop ;[11]
+ ldi x1,0 ;[12] indicate unstuff for bit other than bit6 or bit7
+ in bitcnt, USBIN ;[0] sample stuff bit
+ rjmp unstuff ;[1]
+
+handle0:
+ mov x2, x1 ;[6] Set x2 to current line state
+ ldi bitcnt, 6 ;[7] reset unstuff counter.
+ lsr shift ;[8] shift "0" into the data
+ brcs bit7 ;[9] When after shift C is set, next bit is bit7
+ nop ;[10]
+ rjmp bitloop ;[11]
+
+;----------------------------------------------------------------------------
+; End of receive loop. Now start handling EOP
+;----------------------------------------------------------------------------
+
+macro POP_STANDARD ; 14 cycles
+ pop cnt
+ pop x4
+ pop x3
+ pop x2
+ pop x1
+ pop shift
+ pop bitcnt
+ endm
+macro POP_RETI ; 7 cycles
+ pop YH
+ pop YL
+ out SREG, YL
+ pop YL
+ endm
+
+
+
+#include "asmcommon.inc"
+
+; USB spec says:
+; idle = J
+; J = (D+ = 0), (D- = 1)
+; K = (D+ = 1), (D- = 0)
+; Spec allows 7.5 bit times from EOP to SOP for replies
+; 7.5 bit times is 100 cycles. This implementation arrives a bit later at se0
+; then specified in the include file but there is plenty of time
+
+bitstuffN:
+ eor x1, x4 ;[8]
+ ldi x2, 0 ;[9]
+ nop2 ;[10]
+ out USBOUT, x1 ;[12] <-- out
+ rjmp didStuffN ;[0]
+
+bitstuff7:
+ eor x1, x4 ;[6]
+ ldi x2, 0 ;[7] Carry is zero due to brcc
+ rol shift ;[8] compensate for ror shift at branch destination
+ nop2 ;[9]
+ rjmp didStuff7 ;[11]
+
+sendNakAndReti:
+ ldi x3, USBPID_NAK ;[-18]
+ rjmp sendX3AndReti ;[-17]
+sendAckAndReti:
+ ldi cnt, USBPID_ACK ;[-17]
+sendCntAndReti:
+ mov x3, cnt ;[-16]
+sendX3AndReti:
+ ldi YL, 20 ;[-15] x3==r20 address is 20
+ ldi YH, 0 ;[-14]
+ ldi cnt, 2 ;[-13]
+; rjmp usbSendAndReti fallthrough
+
+;usbSend:
+;pointer to data in 'Y'
+;number of bytes in 'cnt' -- including sync byte [range 2 ... 12]
+;uses: x1...x4, btcnt, shift, cnt, Y
+;Numbers in brackets are time since first bit of sync pattern is sent
+;We don't match the transfer rate exactly (don't insert leap cycles every third
+;byte) because the spec demands only 1.5% precision anyway.
+usbSendAndReti: ; 12 cycles until SOP
+ in x2, USBDDR ;[-12]
+ ori x2, USBMASK ;[-11]
+ sbi USBOUT, USBMINUS;[-10] prepare idle state; D+ and D- must have been 0 (no pullups)
+ in x1, USBOUT ;[-8] port mirror for tx loop
+ out USBDDR, x2 ;[-7] <- acquire bus
+; need not init x2 (bitstuff history) because sync starts with 0
+ ldi x4, USBMASK ;[-6] exor mask
+ ldi shift, 0x80 ;[-5] sync byte is first byte sent
+txByteLoop:
+ ldi bitcnt, 0x49 ;[-4] [10] binary 01001001
+txBitLoop:
+ sbrs shift, 0 ;[-3] [10] [11]
+ eor x1, x4 ;[-2] [11] [12]
+ out USBOUT, x1 ;[-1] [12] [13] <-- out N
+ ror shift ;[0] [13] [14]
+ ror x2 ;[1]
+didStuffN:
+ nop2 ;[2]
+ nop ;[4]
+ cpi x2, 0xfc ;[5]
+ brcc bitstuffN ;[6]
+ lsr bitcnt ;[7]
+ brcc txBitLoop ;[8]
+ brne txBitLoop ;[9]
+
+ sbrs shift, 0 ;[10]
+ eor x1, x4 ;[11]
+didStuff7:
+ out USBOUT, x1 ;[-1] [13] <-- out 7
+ ror shift ;[0] [14]
+ ror x2 ;[1]
+ nop ;[2]
+ cpi x2, 0xfc ;[3]
+ brcc bitstuff7 ;[4]
+ ld shift, y+ ;[5]
+ dec cnt ;[7]
+ brne txByteLoop ;[8]
+;make SE0:
+ cbr x1, USBMASK ;[9] prepare SE0 [spec says EOP may be 25 to 30 cycles]
+ lds x2, usbNewDeviceAddr;[10]
+ lsl x2 ;[12] we compare with left shifted address
+ out USBOUT, x1 ;[13] <-- out SE0 -- from now 2 bits = 22 cycles until bus idle
+ subi YL, 20 + 2 ;[0] Only assign address on data packets, not ACK/NAK in x3
+ sbci YH, 0 ;[1]
+;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm:
+;set address only after data packet was sent, not after handshake
+ breq skipAddrAssign ;[2]
+ sts usbDeviceAddr, x2; if not skipped: SE0 is one cycle longer
+skipAddrAssign:
+;end of usbDeviceAddress transfer
+ ldi x2, 1<<USB_INTR_PENDING_BIT;[4] int0 occurred during TX -- clear pending flag
+ USB_STORE_PENDING(x2) ;[5]
+ ori x1, USBIDLE ;[6]
+ in x2, USBDDR ;[7]
+ cbr x2, USBMASK ;[8] set both pins to input
+ mov x3, x1 ;[9]
+ cbr x3, USBMASK ;[10] configure no pullup on both pins
+ ldi x4, 5 ;[11]
+se0Delay:
+ dec x4 ;[12] [15] [18] [21] [24]
+ brne se0Delay ;[13] [16] [19] [22] [25]
+ out USBOUT, x1 ;[26] <-- out J (idle) -- end of SE0 (EOP signal)
+ out USBDDR, x2 ;[27] <-- release bus now
+ out USBOUT, x3 ;[28] <-- ensure no pull-up resistors are active
+ rjmp doReturn
--- /dev/null
+/* Name: usbportability.h
+ * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers
+ * Author: Christian Starkjohann
+ * Creation Date: 2008-06-17
+ * Tabsize: 4
+ * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
+ * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
+ */
+
+/*
+General Description:
+This header is intended to contain all (or at least most of) the compiler
+and library dependent stuff. The C code is written for avr-gcc and avr-libc.
+The API of other development environments is converted to gcc's and avr-libc's
+API by means of defines.
+
+This header also contains all system includes since they depend on the
+development environment.
+
+Thanks to Oleg Semyonov for his help with the IAR tools port!
+*/
+
+#ifndef __usbportability_h_INCLUDED__
+#define __usbportability_h_INCLUDED__
+
+/* We check explicitly for IAR and CodeVision. Default is avr-gcc/avr-libc. */
+
+/* ------------------------------------------------------------------------- */
+#if defined __IAR_SYSTEMS_ICC__ || defined __IAR_SYSTEMS_ASM__ /* check for IAR */
+/* ------------------------------------------------------------------------- */
+
+#ifndef ENABLE_BIT_DEFINITIONS
+# define ENABLE_BIT_DEFINITIONS 1 /* Enable bit definitions */
+#endif
+
+/* Include IAR headers */
+#include <ioavr.h>
+#ifndef __IAR_SYSTEMS_ASM__
+# include <inavr.h>
+#endif
+
+#define __attribute__(arg) /* not supported on IAR */
+
+#ifdef __IAR_SYSTEMS_ASM__
+# define __ASSEMBLER__ /* IAR does not define standard macro for asm */
+#endif
+
+#ifdef __HAS_ELPM__
+# define PROGMEM __farflash
+#else
+# define PROGMEM __flash
+#endif
+
+#define USB_READ_FLASH(addr) (*(PROGMEM char *)(addr))
+
+/* The following definitions are not needed by the driver, but may be of some
+ * help if you port a gcc based project to IAR.
+ */
+#define cli() __disable_interrupt()
+#define sei() __enable_interrupt()
+#define wdt_reset() __watchdog_reset()
+#define _BV(x) (1 << (x))
+
+/* assembler compatibility macros */
+#define nop2 rjmp $+2 /* jump to next instruction */
+#define XL r26
+#define XH r27
+#define YL r28
+#define YH r29
+#define ZL r30
+#define ZH r31
+#define lo8(x) LOW(x)
+#define hi8(x) (((x)>>8) & 0xff) /* not HIGH to allow XLINK to make a proper range check */
+
+/* Depending on the device you use, you may get problems with the way usbdrv.h
+ * handles the differences between devices. Since IAR does not use #defines
+ * for MCU registers, we can't check for the existence of a particular
+ * register with an #ifdef. If the autodetection mechanism fails, include
+ * definitions for the required USB_INTR_* macros in your usbconfig.h. See
+ * usbconfig-prototype.h and usbdrv.h for details.
+ */
+
+/* ------------------------------------------------------------------------- */
+#elif __CODEVISIONAVR__ /* check for CodeVision AVR */
+/* ------------------------------------------------------------------------- */
+/* This port is not working (yet) */
+
+/* #define F_CPU _MCU_CLOCK_FREQUENCY_ seems to be defined automatically */
+
+#include <io.h>
+#include <delay.h>
+
+#define __attribute__(arg) /* not supported on IAR */
+
+#define PROGMEM __flash
+#define USB_READ_FLASH(addr) (*(PROGMEM char *)(addr))
+
+#ifndef __ASSEMBLER__
+static inline void cli(void)
+{
+ #asm("cli");
+}
+static inline void sei(void)
+{
+ #asm("sei");
+}
+#endif
+#define _delay_ms(t) delay_ms(t)
+#define _BV(x) (1 << (x))
+#define USB_CFG_USE_SWITCH_STATEMENT 1 /* macro for if() cascase fails for unknown reason */
+
+#define macro .macro
+#define endm .endmacro
+#define nop2 rjmp .+0 /* jump to next instruction */
+
+/* ------------------------------------------------------------------------- */
+#else /* default development environment is avr-gcc/avr-libc */
+/* ------------------------------------------------------------------------- */
+
+#include <avr/io.h>
+#ifdef __ASSEMBLER__
+# define _VECTOR(N) __vector_ ## N /* io.h does not define this for asm */
+#else
+# include <avr/pgmspace.h>
+#endif
+
+#if USB_CFG_DRIVER_FLASH_PAGE
+# define USB_READ_FLASH(addr) pgm_read_byte_far(((long)USB_CFG_DRIVER_FLASH_PAGE << 16) | (long)(addr))
+#else
+# define USB_READ_FLASH(addr) pgm_read_byte(addr)
+#endif
+
+#define macro .macro
+#define endm .endm
+#define nop2 rjmp .+0 /* jump to next instruction */
+
+#endif /* development environment */
+
+/* for conveniecne, ensure that PRG_RDB exists */
+#ifndef PRG_RDB
+# define PRG_RDB(addr) USB_READ_FLASH(addr)
+#endif
+#endif /* __usbportability_h_INCLUDED__ */