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Modbus TCP Server - TCP error 16#C210

rriveralrriveral
edited August 2021 in PLCnext Engineer
I am using the library Modbus TCP 8.

When I try to set up the server, there is always a TCP error.

16#C040 16#xxxx TCP_SEND error 16#xxxx. Refer to appendix.
16#C210 The application tried to send or receive data, and the Socket is not connected (_SOCKET.ACTIVE == False).


block settings

MB_TCP_Server_51(
xActivate := xTestMBServerActivate,
xAcknowledge := MBServer.xAcknowledge,
xAutoAck := MBServer.xAutoAck,
xUDP := MBServer.xUDP_Mode,
strBindIp := '',
uiBindPort := UINT#504,
strDestIp := '',
uiDestPort := UINT#0,
tReconnectDelay := t#500ms,
tTimeout := t#0s,

uiOffsetInputRegister := UINT#150,
uiOffsetHoldingRegister := UINT#99,
uiOffsetInputs := UINT#50,
uiOffsetCoils := UINT#0,

xActive => MBServer.xActive,
xConnected => MBServer.xConnected,
xError => MBServer.xError,
wDiagCode => MBServer.wDiagCode,
wAddDiagCode => MBServer.wAddDiagCode,
udtDiag => MBServer.udtDiag,
arrModbusData := MBServer.arrModbusData);

Comments

  • Martin [PLCnext Technology Team]Martin [PLCnext Technology Team]
    What version of PLCnext Engineer are you using?
    According to the documentation, Modbus TCP library version 8 is designed for PLCnext Engineer version 2020.0 LTS.
    The recently released Modbus TCP library version 9 is designed for PLCnext Engineer version 2021.0 LTS.
  • rriveralrriveral
    I am currently using.

    2020.0 LTS

    The main question is for Modbus TCP 8 library, is it possible to fix the problem?

    I started to test version Modbus TCP 9, but still I get some errors.
    and now I get 16#C030 and 16#C205
  • rriveralrriveral
    Both libraries seem to not be stable, can you please advise?

    Thank you.
  • rriveralrriveral
    I have another question, perhaps you can help me.

    I was using 2020.0 LTS
    Now I installed the PLC next engineer version 2021.3.1
    Do I need to upgrade the PLC firmware?
  • rriveralrriveral
    One more question,

    I am getting the following error code

    16#C205
    Only one use of an address is normally permitted

    What does this really means and how to fix it ?

    Thank you.
  • rriveralrriveral
    One more problem.

    Is seems that the server dies at some point, but it does not show any error, in this state no data can be requested to the server, see attached image.
  • Martin [PLCnext Technology Team]Martin [PLCnext Technology Team]
    I will need to put all those questions to the developers of the Modbus TCP library, but it will be Monday before they see the questions.

    It is also possible to contact the developers directly using the "Contact" button on the PLCnext Store page.

    I can answer one question:
    I installed the PLC next engineer version 2021.3.1
    Do I need to upgrade the PLC firmware?
    Short answer: No.
    However, it is always recommended to keep the PLC firmware upgraded to the latest LTS version, at least, to get the benefit of security improvements and other enhancements.

    Also please note the recommended PLCnext Engineer versions for the different versions of the Modbus TCP libraries. The developers will probably recommend that you use exactly the recommended version (no earlier and no later).
  • Martin [PLCnext Technology Team]Martin [PLCnext Technology Team]
    Answer from development:
    Please always use the newest version of the library. In this case Modbus_TCP_9.
    With the AXC_F_2152 you can only run one MB_TCP_Server.
    If there are more than one Server, you get the error 16#C030 // 16#C205.
    (ref: #219047)
  • rriveralrriveral
    Hello,

    I have tested the new version, it was a bit more stable.

    here are the metrics.


    We still get errors. we are running requests at a second level to a meter which is next to the PLC and we have gotten 0 errors so far, and the PLC shows 9 errors over approx 65000 requests.

    The PLC server on the code itself does not record any error flag, but it's not possible to request data at some point.

    Also, interesting, that the response time for the Modbus message is not constant, it ranges from 200ms up to 1900 ms.

    Finally, after testing for one entire day, the server becomes unresponsive, it dies but shows no error, so you basically can request data to it but on the code it seems that everything is fine...
    I think the last point is really critical, since there is no acknowledgement of error from the system, this library shall not be used.

    Any hint? on how to solve?

    The test was performed
    PLC engineer next 2021.3.1
    Modbus TCP 9 library

    PLC AXC_F_2152 - 2020 / hw 02
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