diff --git a/pic/MDR/I2C.c b/pic/MDR/I2C.c
index 3da593e..54b2056 100644
--- a/pic/MDR/I2C.c
+++ b/pic/MDR/I2C.c
@@ -120,12 +120,12 @@ uint8_t read_byte(uint8_t ack)
 	for (bit=0; bit<8; bit++) {
 		delay(); /* wait for SDA to change */
 		release_SCL(); /* SDA should be valid when clock is high */
+		byte <<= 1; /* make place to save the next bit */
 		if (PORTB&SDA) { /* read bit */
 			byte += 1;
 		} else {
 			byte += 0;
 		}
-		byte <<= 1;
 		hold_SCL(); /* set clock to low for SDA to change */
 	}
 	if (ack) {