-unsigned char xdata ser_txIndexIn;
-unsigned char xdata ser_txIndexOut;
-unsigned char xdata ser_rxIndexIn;
-unsigned char xdata ser_rxIndexOut;
+unsigned char __xdata ser_txIndexIn;
+unsigned char __xdata ser_txIndexOut;
+unsigned char __xdata ser_rxIndexIn;
+unsigned char __xdata ser_rxIndexOut;