自动报警系统，是结合单片机与VB界面，串口的一个应用实例，很好地学习通信应用-Automatic alarm system, is a combination of single chip computer and VB serial interface, an application example, a good learning communication application

PC与三菱PLC串口通信 C#实例源程序 -PC with mitsubishi PLC serial communication example source code