I m beginner with Modbus communication. My task is to all digital inputs from PLC put in register and enable communication with BMS center. People from BMS center can just read state of inputs, not change. I want to create register with information as below:
%I0.1.0 %MW10.0 40011: bit 0 %I0.1.1 %MW10.1 40011: bit 1 %I0.1.2 %MW10.2 40011: bit 2
I would create an integer variable with the correct Modbus address and do the mapping in a ST program (see attachment). If you were using a M580 you do this all in one go with Alias'. You would map the IO card drop, slot and channel to the variable in the 'Alias of' column and but the desired Modbus address in the 'Address' column. But you can't do this with the M340 I am pretty sure (could be wrong, I mostly work with the M580).