利用8088/86CPU控制8251A可编程串行通信控制器，实现单机的自发自收模式。发送方读入按键值，并发送给接收方，接收方收到数据后，从左到右，第五位LED数码显示本机的键入按键代码，第六位显示接收到的数据在LED数码管上显示。-Control the use of 8088/86CPU 8251A programmable serial communications controller, to achieve single mode of spontaneous self-closing. Read key value for the sender and sent the receiver, the receiver receives the data, from left to right, the fifth digit LED display keys of the machine type code, sixth in the display data received in the LED digital tube on the display.