利用第三方软件（如VB）开发S7-300PLC与上位机进行MPI通讯的源码实例！非常珍贵！-The use of third-party software (such as VB) development of S7-300PLC to MPI communication with the host computer source code examples! Very precious!

S7通过MPI和VB通讯，每行都加入了新的注释，适合新手学习。-VB TO MPI S7 CONNECT

vb与西门子s7-300和PC通讯的例子程序源代码-vb s7-300 PC communication