Nest the second loop inside the other

rtty.c

@@ -68,8 +68,7 @@ void rtx_init()
 void inline rtx_wait()
 {
 	/* Wait for interrupt driven TX to finish */
-	while(txlen > 0);
-	while(txlen > 0);
+	while(txlen > 0) while(txlen > 0);
 }
 
 void rtx_data(uint8_t *data, size_t length)