这是本人在网上搜索了很久才找到的PLC与上位机通讯的相关论文，希望大家喜欢。-this is my online search for a long time to find the PLC and PC communications related papers, hope you like them.

串口通讯工具，支持短信猫和普通串口通讯，用的多线程处理-Serial communication tools to support text messaging and the general cat serial communication, use of multi-threading