VC++编写的Modbus协议的上位机程序，可作为数据采集模块的上位机程序或者Modbus设备的测试程序。-VC++ written in Modbus protocol host computer program can be used as data acquisition modules, host computer program or Modbus device testing procedures.

用VB写的通讯协议Modbus RTU ,希望前辈指教! -Written in VB communication protocol Modbus RTU, hope predecessors advice!

VB编写的与PLC通信 Modbus RTU协议通讯源程序-Written in VB and PLC communication Modbus RTU protocol communications source