单片机与上位机PC的通信程序设计方法： ⑴串口初始化：波特率定为4800 ⑵串口接收数据：串口初始化后处于数据接收状态，当有数据到达串口时，串口将数据接收保存在寄存器中暂存 ⑶串口发送数据：等数据接收完成后，将寄存器中暂存的数据通过串口发送给该数据的来源地。-PC-MCU and host computer communication program design: ⑴ serial port initialization: the baud rate as 4800 ⑵ serial receive data: the serial port is initialized in the data receiving state, when serial data arrives, the serial port to receive data stored ⑶ in temporary register serial send data: such data reception is completed, the temporary register in the data sent through the serial port to the data source.