diff --git a/software/sss7core/sss7.h b/software/sss7core/sss7.h
index 7e82f8e..d3fca59 100644
--- a/software/sss7core/sss7.h
+++ b/software/sss7core/sss7.h
@@ -48,7 +48,7 @@ static inline uint8_t sss7_send_failed(void) {
 }
 
 static inline uint8_t sss7_has_received(void) {
-	return sss7_rx_oldest_buffer < sss7_rx_active_buffer;
+	return sss7_rx_oldest_buffer != sss7_rx_active_buffer;
 }
 
 void sss7_get_received(uint8_t msg[SSS7_PAYLOAD_SIZE]);