diff --git a/src/wiiuse.c b/src/wiiuse.c
index e09987e..f58d1bb 100644
--- a/src/wiiuse.c
+++ b/src/wiiuse.c
@@ -583,7 +583,7 @@ int wiiuse_write_data(struct wiimote_t* wm, unsigned int addr, const byte* data,
  *	to a pending list and be sent out when the previous
  *	finishes.
  */
-int wiiuse_write_data_cb(struct wiimote_t *wm,uint addr,unsigned char *data,unsigned char len,wiiuse_write_cb write_cb)
+int wiiuse_write_data_cb(struct wiimote_t *wm, unsigned int addr, byte *data, byte len, wiiuse_write_cb write_cb)
 {
 	struct data_req_t* req;
 
diff --git a/src/wiiuse.h b/src/wiiuse.h
index 5d7524f..fcf1336 100644
--- a/src/wiiuse.h
+++ b/src/wiiuse.h
@@ -761,8 +761,8 @@ typedef enum data_req_s
  */
 struct data_req_t {
 
-	unsigned char data[21];					/**< buffer where read data is written						*/
-	unsigned int len;
+	byte data[21];					/**< buffer where read data is written						*/
+	byte len;
 	unsigned int addr;
 	data_req_s state;			/**< set to 1 if not using callback and needs to be cleaned up	*/
 	wiiuse_write_cb cb;			/**< read data callback											*/