diff --git a/include/hydrolink/protocol.h b/include/hydrolink/protocol.h
index 4ae4311..37b425f 100644
--- a/include/hydrolink/protocol.h
+++ b/include/hydrolink/protocol.h
@@ -21,6 +21,7 @@ typedef struct {
 * @param msg_id the message's id
 * @param crc[out] the crc_extra byte as output of this function
 * @return Return 1 if successfull, 0 otherwise.
+**/
 static inline uint8_t hydrolink_get_crc_extra(uint8_t msg_id, uint8_t *crc) {
   static const hydrolink_crc_extra_t crcs[] = HYDROLINK_MSG_CRCS;
   uint8_t left = 0;
@@ -35,7 +36,7 @@ static inline uint8_t hydrolink_get_crc_extra(uint8_t msg_id, uint8_t *crc) {
       left = center;
       continue;
     }
-    left = mid;
+    left = center;
     break;
   }
   if (crcs[left].msg_id != msg_id) {