关于污水处理厂中生化池中溶解氧的控制，程序使用的是一般的PID控制，PLC模块存放在PLC的CPU中，m文件中有OPC通讯。-About sewage treatment plant biochemical control of dissolved oxygen in the pool, the program uses the general PID control, PLC module is stored in the PLC CPU, m is the file has OPC comm

用VB实现的Client,实现S7—PLC和计算机通信,遵照OPC协议实现-Using VB to achieve the Client, the realization of S7- PLC and computer communication, according to the OPC protocol implementation

PLC通讯试验OPC，仅作试验用,不错的学习资料，值得一学(PLC communication test OPC, just for testing, good learning materials, it is worth learning)