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北京科技大学讲解的PLC--S7-200视频信息列表，多多指教，我也是刚开始，总结了一下-Lecture at Beijing University of Science and Technology PLC- S7-200 video list of the exhibitions, I am also the beginning, summed up what

通过C#实现串口编程通讯，供大伙学习参考，不用谢，不客气(You are welcome ,Don't mention it .Do you miss me ,I like you very mach.)