I am working with a Nematron MT8070iH touch screen HMI. I have set the PLC up as MODBUS ASCII with RS-232 communication (38400,N,8,1). I am able to read output status from the plc but cannot write to Inputs.
If I understand correctly, no special configuration needs to be done in my code on the PLC for MODBUS communication. And since I seem to be able to read outputs with a MODBUS address from the HMI it looks like I am correct in that thought process.
I am not sure what is going on. I have tried different timeout settings on the HMI with no luck.
Any help will be appriciated.