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Modbus TCP; CoDeSys V3.5

Is the DeltaV Ethernet I/O Card (EIOC) Interface, with Modbus TCP master firmware, able to communicate with CoDeSys Modbus TCP slave?

Has anybody some experience with CoDeSys V3.5?

Regards,
Ed.

Possible issues:

1) The EIOC supports only the Modbus TCP standard protocol;
the RTU via TCP and RTU via UDP are not supported in the EIOC.
Does CoDeSys use the "Modbus TCP standard protocol".
(I could not this information in any documentation.)

2) Modbus function code 8 and sub-function code 00 (echo request).
Does CoDeSys support :code 8"?
(In the documentation, "code 8" was not in the supported code list.)

3) Modbus TCP: Uses MODICON (PLC) based addressing (Modbus absolute addressing is not supported)
Which addressing is used by CoDeSys?
(CoDeSys does -not- specify which protocol is implemented.)

https://www.emerson.com/documents/automation/s-series-ethernet-i-o-card-en-57652.pdf

Modbus TCP;  CoDeSys V3.5

2 Replies

  • I will borrow a DeltaV test setup, with EIOC, and investigate if the Modbus TCP master is able to communicate with a PLC with CoDeSys V3.5 Modbus TCP slave.
    Regards,
  • The two devices are exchanging data. Test passed.