基于API串口通信程序，可以进行监控演示系统demo-serial communication procedures, monitoring demonstration system demo

本源代码演示了通过串口利用MPI协议与西门子PLC S7-300系统通讯的实现方式。,Demo source code through the serial port using MPI agreement with Siemens PLC S7-300 system, ways of communication.