Connection TM221CE16R

[Yousef656]

Hello,

I have two Modicon M221 TM221CE16R PLCs that I want to connect together over a fiber link. 

Each PLC is connected to a media converter (Ethernet RJ45 ↔ fiber).

My goal is:

- One PLC acts as the master.

- The other PLC acts as the slave.

- The master needs to read 5 bits from the slave and write 2 bits to it.

My questions are:

1) Is it a good practice to configure one PLC as a Modbus TCP Server and the other as a Modbus TCP I/O Scanner for this application?

2) If I use the Modbus TCP I/O Scanner, is it enough on the master side, or do you also recommend using READ_VAR / WRITE_VAR function blocks on one or both PLCs?

Thank you in advance.