EASY4 MODBUS RTU - SLAVE NOT COMMUNICATING

[AlesH]

Hi all,
I'm straggling to find away to communicate with COM-RTU-M1 as master and relay module as slave (waveshare modbus RTU Reley 32CH).
my setup:
CPU: easy-E4-DC-12TCX1 (V2.30)
Easysoft v8.3
Master:
easy-COM-RTU-M1
Slave:
https://www.waveshare.com/modbus-rtu-relay-32ch.htm
I have also try with other RTU relay module - R4D3B16 (https://italian.alibaba.com/product-detail/R4D3B16-DC-12V-16CH-10A-DIN-1601044364905.html) with same issue.

The waveshare has default configuration as ID address 1, the other one R4D3B16 the ID can be set with dipswitch.

I have try different configuration with both of them, with no results.
Not clear is also addressing with functional code in my case I need to use FC5-write single coil which for modbus RTU address start from 56001 for modbus TCP the FC5 functional code address starts with 1001.
How should correctly addressed to activate from the program a single coil on one of that relay module.
Please share your point of view or samples how did you manage such issue