Connect a CJ1M-ETN21 as slave Modbus TCP

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I'm trying to connect a CJ1M-ETN21 as slave Modbus TCP with a Modbus/Dali Gateway. I download from Omron website some FB with ones should be possible.  

The FB only can be used with the direction unit 0, but we can change some directions inside the FB and can be adjusted to other units. In the download I found this FB:

MTCP_ETN_Connect, MTCP_ETN_Fn01, MTCP_ETN_Fn02, MTCP_ETN_Fn03 ....

Supposed with connect we can establish the connection with the master, but the FB never make nothing. Should I make some special configurations to use this FB?

I appreciate any help.


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@APerez for reference by attached files for use Modbus TCP Server Function Block you need to only on Start_Server contact at EN pin odf function block.


But for this function block it cannot support to read coil or input register


Then when your Modbus Client send request command to PLC it will respond as this table below.




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Hello Wasan, thanks for your answer. But I really need to use the CJ1w-ETN21 as client (ask the gateway for information). The only blocks I found in myomron was the ones I mention in the first comment, and I don't found the way to put them on.

Supposed with MTCP_ETN_Connect you put the IP address of the server and activate EN, and the connection go ON, but the FB don't connect and don't show errors.

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@APerez for use OMRON PLC to Modbus Client then as reference manual you should On at MTCP_ETN_Connect at "EN" pin to enable and Set pin "Connect" to ON for request communication if you use example program that include with function block this pin output with contact "Connected" then use pin this contact to enable other Modbus FCXX function block at EN pin for example Fn03 to read data register you should on "Cmd_Read" to read data for other describe below

Register_Address : Start address register

Register_Qty : set how many word to read

RespData_DM : which DM to receive data from Modbus

Cmd_Read : On for read Modbus data

SalveID : define Modbus ID device


Then you shoukd check Function Block manual they describe that how to setting them.


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