MODBUS TCP - ZBRN1 (Schneider Electric)

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Has anyone got an Omron PLC NX1P2-1140DT1 running with Modbus TCP/IP?

I tried to reach Schneider several times, but there is "live" or email to discuss or get help, has to go to thru someone from Mexico then he will email to France.
All of my attempts was lost, I can establish a "CONNECTION" but I can't READ the Coil - I got the error "Gateway Path Unavailable" (that means  "Used alongside gateways. Basically, this code means the gateway couldn’t allocate an internal path to process the request. Therefore, the gateway could probably be misconfigured or overloaded")

My program is based on the MTCP_Client_NJ_E (Revision 2.3 date 23/07/2021 - JP Viskovic from France)

I can read the coils using MODBUX Doctor (France) but I can't make work with Etherway.

Any advice is welcome.NX1P2_ZBRN1.JPG.5ea08afa63c96c710e2770da





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Your screen shot shows Unit ID == 0 and Qty == 0.  Unit ID 0 is defined as a broadcast cmd with no expected reply (though some Modbus implementations respond to it anyways). Are you sure your slave unit is supposed to be zero?

Qty==0 is always invalid.  How many consecutive coils do you want to read?

Also note that coil "000001" is really address == 0 within the protocol, so that might be wrong, too.  (Some modbus implementations screw that up, too, unfortunately.)

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255 is usually what you use as a unit ID, in addition to the items pturmel mentioned. If you want to see exactly what the slave is replying with open your watch tab page table and monitor Program0.Client_ReadCoils.Recv_Data. This is the inbound buffer and you can easily decode the response

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I found the problem, my ZBRN1 is Unit ID 248 not 255.

And the Coil Address is 0000 - qty as many coils we want to read.

Thanks for the advice.


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