I recently with a touch screen, need VC write ModbusTCP/IP program to realize data read and write the PLC and the upper machine, PC is the client, the PLC is the server, which can pass code, thank you! The mailbox 125771305 qq.com

CodePudding user response:

First of all, you are going to have a look at the Modbus rtu protocol, Modbus TCP with Modbus rtu, the difference is that TCP is cancelled check code, other are largely consistent, the definition of the Modbus TCP, it should be relatively simple, long look documents, combined with PLC memory address named, was no problem