Move data to holding register to read through modbus TCP

Hi All,

I am still very new in Modbus communication. I got a project to get data out from PLC controller LMC078 through Modbus TCP.
The variables I got is FAULT1 and has been declared in a GVL
VAR_GLOBAL PERSISTENT RETAIN
FAULT1 :INT;
END_VAR
The value FAULT1 will receive from a POU will give the FAULT1 a value to show what type of fault is that.

I want to move the value from FAULT1 to Holding register so that I can read using FC3 through modbus - for ex:


Could you please show me how to do that? or guide me through where to start?

Thank you so much
Harry