I am a layman, using c # to do secondary development, in the previous year with schneider M221 communication, through the Modbus protocol can read and write the address, but have to do now is M241 PLC, found with M221 communication is a bit different, very few examples on the net, only some information from the main station, such as amateurs so don't understand, please do M241 communication provides the technical support and communication code,
Provide the address of a bit don't understand, and PLC such as % WM522, % MW7: X10, is not the same as M221 address

I downloaded the modbus modscan32 online debugging tools, have been debug,



First of all, to be sure:
1, M241 PLC hardware is no problem, can directly with the original PLC touch screen communication, can read and write data normally,
There is no question of 2485 serial port, with M221 can normal communication,

CodePudding user response:

Adress should be modbus station number
Id should be a PLC device address, this address different equipment is different, you should check the instructions