Hi, could you please help me to understand how to read Siemens S7 1200 registers starting from the following input?
To interact with the PLC I have an OP operate panel (Xinje OP320) connected via RS 485.
I need to read the same data just quering the PLC but via standard modbus TCP IP, and for this I'm using node-red-contrib-modbus.
I've tryed several ways but nothing. The OP works correctly, and here you can see a testing page:
In this case I should use:
- FC3 function (read holding registers) / FC4 function (read holding registers)
- address: 172
- quantity: 2
Right?
But I don't get any data, any errors, nothing
Thanks