C51独立键盘控制,K1控制LED灯全灭，K2控制灯全亮，K3控制灯向左闪烁，K4控制向右闪烁。-C51 independent keyboard control,K1 control the LED to put off while K1 control the LED to put on K3 control the LED to light on　right to left while K3 control the LED to light on　left to right.