甲乙两台80C51单片机串行通信，一台通过开关控制P1口的高低电平并发送数据，另一台接收发送过来的数据，通过P1口用发光二极管显示，高电平点亮，低电平熄灭。-A and B two 80C51 microcontroller serial communication, a switch control through the high-low P1 port and send the data to send over another to receive the data, through t