Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

Protocol Error after connecting to TCPModbus Device



  • Hi all,

    the code

    if (reply->error() == QModbusDevice::ProtocolError)
    {
          qDebug()<<"Write response error: %1 (Mobus exception: 0x%2";
          qDebug()<<reply->errorString();
          qDebug()<<reply->rawResult().exceptionCode();
    }
    

    responses with the following error

    2021-06-21 14:16:30.750 DBG default: Write response error: %1 (Mobus exception: 0x%2
    2021-06-21 14:16:30.750 DBG default: "Modbus Exception Response."
    2021-06-21 14:16:30.750 DBG default: 3
    

    after the connection to a TCPModbus coupler is established (connected signal is already triggered). Unfortunately, I cannot find any hint in the documentation on the reason of this error.

    Any ideas?

    Thanks a lot.


Log in to reply