为单位开发的控制界面。实现了与西门子PLC的通信（采用PPI控件），word表格生成，数据库的构建。-Developed for the control interface unit. Achieved with the Siemens PLC communication (PPI controls used), word form generation, to build the database.

vb与access结合做的学生管理系统，适合初学者-vb and s7-200plc communication source, not control. PPI protocol for understanding