diff --git a/src/main/drivers/serial.c b/src/main/drivers/serial.c
index bb81d3dd8..8a17ce679 100644
--- a/src/main/drivers/serial.c
+++ b/src/main/drivers/serial.c
@@ -56,7 +56,7 @@ void serialWriteBuf(serialPort_t *instance, uint8_t *data, int count)
     }
 }
 
-uint8_t serialRxBytesWaiting(serialPort_t *instance)
+uint32_t serialRxBytesWaiting(serialPort_t *instance)
 {
     return instance->vTable->serialTotalRxWaiting(instance);
 }
diff --git a/src/main/drivers/serial.h b/src/main/drivers/serial.h
index d8f868ae7..1f75e931d 100644
--- a/src/main/drivers/serial.h
+++ b/src/main/drivers/serial.h
@@ -81,7 +81,7 @@ struct serialPortVTable {
 };
 
 void serialWrite(serialPort_t *instance, uint8_t ch);
-uint8_t serialRxBytesWaiting(serialPort_t *instance);
+uint32_t serialRxBytesWaiting(serialPort_t *instance);
 uint8_t serialTxBytesFree(serialPort_t *instance);
 void serialWriteBuf(serialPort_t *instance, uint8_t *data, int count);
 uint8_t serialRead(serialPort_t *instance);