Add w1_read_bit() to improve waiting for result

[temper-clone.git] / w1.c

diff --git a/w1.c b/w1.c
index 8217602e0dcaa277ace9d3614ba47c54d420e56a..add1b4895c82d0f6484d213408629581bc686d69 100644 (file)
--- a/w1.c
+++ b/w1.c
@@ -65,26 +65,35 @@ void w1_write(uint8_t val)
        }
 }
 
+bool w1_read_bit()
+{
+       bool val;
+
+       ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
+       {
+               /* Pull low for 6µs */
+               DDRB |= 1 << W1_PIN;
+               _delay_us(6);
+               /* Release for 9µs */
+               DDRB &= ~(1 << W1_PIN);
+               _delay_us(9);
+
+               /* Read the line state */
+               val = ((PINB >> W1_PIN) & 1);
+       }
+       _delay_us(55);
+
+       return val;
+}
+
 uint8_t w1_read_byte()
 {
        uint8_t i, val;
 
        val = 0;
        for (i = 0; i < 8; i++) {
-               ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
-               {
-                       /* Pull low for 6µs */
-                       DDRB |= 1 << W1_PIN;
-                       _delay_us(6);
-                       /* Release for 9µs */
-                       DDRB &= ~(1 << W1_PIN);
-                       _delay_us(9);
-
-                       /* Read the line state */
-                       val |= ((PINB >> W1_PIN) & 1) << i;
-               }
-
-               _delay_us(55);
+               if (w1_read_bit())
+                       val |= (1 << i);
        }
 
        return val;