I am setting up a Modbus RTU Master OPC Server to talk to a Quantum PLC. Anyone know a particular Modbus RTU Master OPC Server which can be run in "Program Master" mode?

Normally, Modbus RTU Master OPC Servers are just "Data Master". I need it as a "Program Master" because I need to write to 1xxxx & 3xxxx addresses of the PLC which are normally Read ONly. Any help appreciated

 

"Program Master" and "Data Master" are Modbus-Plus terms. Modbus-Plus supports 8 data master paths and 8 program master paths per NIC. I'm guessing that's where you picked up those terms.

There are no standard Modbus function code to write to 1x and 3x data types.

 

Do you have the info how to setup those "Progam Master" paths on MB Plus? Sounds to me these "Program Master" paths also exist on the Ethernet port.

Thanks for your help.