基于PLC的PID上位机控制，可以控制三菱的PLC，有曲线显示，可以实现数据保存和再显示-PLC-based PC PID control, the control of Mitsubishi PLC, a curve, Data can be preserved and shows again and again

vb源程序，通过vb与三菱PLC通信，源代码-Vb Mitsubishi PLC through communication with the communication with the PLC by Mitsubishi vb