Hello out there in HE land
I am reaching out for help because I have the above devices and cannot make heads nor tails of the documentation.
Objective:
Use an external modbus client to communicate with the PLC and change bits in the MC memory, read bits in the MI memory and read words in the MHR memory.
I've set up the module with an IP (192.168.42.2) using netedit and has module ID 0. But There is a lot of jargon that is confusing. The modbus support module for EPICS (noted below) asks for a unit id . Fair enough. I simply used 0. I am able to use the PLC simulator to write to modbus memory MI, MC, and read from MHR. But once I switch to the hardware, I cannot read anything. I cannot write anything.
I've looked at the FAQ0038 for Modbus and ECOM100 and I am at a loss. There is no mention of being able to access the MI, MC, MHR, or MIR blocks or what the mapping might be.
Moreover, in another post about communitcating via the ECOM100, setting up a "Peer-to-Peer configuraiton" in NetEdit added to the confusion, there is a unit ID set to 255 by default and an Rx/Wx number set to 1.
Does anyone have any insight? I'm pulling my hair out.
The external controller framework is here on github
https://github.com/epics-modules/modbus/blob/master/iocBoot/iocTest/Koyo1.cmdI have tried almost everything. But it's non-trivial to modify the EPICS drivers as they are tightly coupled to databases.