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Modbus TCP Client write holding registers

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  • D Damian7546

    @jsulm said in Modbus TCP Client write holding registers:

    @Damian7546 I'm also wondering why you use threads at all?
    If you need to do something periodically then simply use QTimer.

    I would like to run Client on thread and test with several clients(threads) ... how will it be with stability and read/write speed,
    So how define wr_redy in *.h file ?

    jsulmJ Offline
    jsulmJ Offline
    jsulm
    Lifetime Qt Champion
    wrote on last edited by
    #13

    @Damian7546 said in Modbus TCP Client write holding registers:

    So how define wr_redy in *.h file ?

    Don't define it as lambda, but a normal method.

    https://forum.qt.io/topic/113070/qt-code-of-conduct

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    • jsulmJ jsulm

      @Damian7546 said in Modbus TCP Client write holding registers:

      So how define wr_redy in *.h file ?

      Don't define it as lambda, but a normal method.

      D Offline
      D Offline
      Damian7546
      wrote on last edited by Damian7546
      #14

      @jsulm How do I do that?
      When I declare my function in *.h file :
      void wr_redy();

      And I will create definition this function outside my run() function , I do not have acces to variables defined in run()...

      jsulmJ 1 Reply Last reply
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      • D Damian7546

        @jsulm How do I do that?
        When I declare my function in *.h file :
        void wr_redy();

        And I will create definition this function outside my run() function , I do not have acces to variables defined in run()...

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #15

        @Damian7546 If you want to connect a lambda to a signal then do it properly:

        connect(this, ClientMachine1::holdRegArrayChanged, this, wr_redy);
        

        wr_redy is NOT a member of your class, so simply do not prefix it with your class name.

        https://forum.qt.io/topic/113070/qt-code-of-conduct

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        • jsulmJ jsulm

          @Damian7546 If you want to connect a lambda to a signal then do it properly:

          connect(this, ClientMachine1::holdRegArrayChanged, this, wr_redy);
          

          wr_redy is NOT a member of your class, so simply do not prefix it with your class name.

          D Offline
          D Offline
          Damian7546
          wrote on last edited by
          #16

          @jsulm said in Modbus TCP Client write holding registers:

          @Damian7546 If you want to connect a lambda to a signal then do it properly:

          connect(this, ClientMachine1::holdRegArrayChanged, this, wr_redy);
          

          wr_redy is NOT a member of your class, so simply do not prefix it with your class name.

          Right

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          • D Offline
            D Offline
            Damian7546
            wrote on last edited by
            #17

            @jsulm Unfortunetly my write function still doesn't work:/

            auto wr_redy = [&](){
                        for(int i=0; i < m_holdRegArray.count(); i++){
                            qDebug() << "count: " << i;
                            wr.setValue(i, m_holdRegArray[i]);
                        }
                };
            

            The application was crash when it wr.setValue(i, m_holdRegArray[i]); is called...

            jsulmJ 1 Reply Last reply
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            • D Damian7546

              @jsulm Unfortunetly my write function still doesn't work:/

              auto wr_redy = [&](){
                          for(int i=0; i < m_holdRegArray.count(); i++){
                              qDebug() << "count: " << i;
                              wr.setValue(i, m_holdRegArray[i]);
                          }
                  };
              

              The application was crash when it wr.setValue(i, m_holdRegArray[i]); is called...

              jsulmJ Offline
              jsulmJ Offline
              jsulm
              Lifetime Qt Champion
              wrote on last edited by
              #18

              @Damian7546 said in Modbus TCP Client write holding registers:

              The application was crash when

              So, did you use debugger to see why it crashes?
              What is wr?

              https://forum.qt.io/topic/113070/qt-code-of-conduct

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              • D Offline
                D Offline
                Damian7546
                wrote on last edited by
                #19

                @jsulm When I have status: "ModbusTCPClient is disconnected" my app crash when I try write registers..

                jsulmJ 1 Reply Last reply
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                • D Damian7546

                  @jsulm When I have status: "ModbusTCPClient is disconnected" my app crash when I try write registers..

                  jsulmJ Offline
                  jsulmJ Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on last edited by
                  #20

                  @Damian7546 Then don't write registers if there is no connection...

                  https://forum.qt.io/topic/113070/qt-code-of-conduct

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                  • jsulmJ jsulm

                    @Damian7546 Then don't write registers if there is no connection...

                    D Offline
                    D Offline
                    Damian7546
                    wrote on last edited by
                    #21

                    @jsulm I was wrong, sometimes app was crash when I try write value. I get message like below :

                    QSocketNotifier: Socket notifiers cannot be enabled or disabled from another thread
                    QObject: Cannot create children for a parent that is in a different thread.
                    (Parent is QModbusTcpClient(0x504f8fc), parent's thread is ClientTicketMach(0x1215a30), current thread is QThread(0x11c0b28)
                    QObject::startTimer: Timers cannot be started from another thread
                    Error Modbus TCP CLient read:  QModbusDevice::TimeoutError
                    QObject::killTimer: Timers cannot be stopped from another thread
                    
                    jsulmJ 1 Reply Last reply
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                    • D Damian7546

                      @jsulm I was wrong, sometimes app was crash when I try write value. I get message like below :

                      QSocketNotifier: Socket notifiers cannot be enabled or disabled from another thread
                      QObject: Cannot create children for a parent that is in a different thread.
                      (Parent is QModbusTcpClient(0x504f8fc), parent's thread is ClientTicketMach(0x1215a30), current thread is QThread(0x11c0b28)
                      QObject::startTimer: Timers cannot be started from another thread
                      Error Modbus TCP CLient read:  QModbusDevice::TimeoutError
                      QObject::killTimer: Timers cannot be stopped from another thread
                      
                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #22

                      @Damian7546 As all these errors tell you: do the threading properly!

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

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                      • D Offline
                        D Offline
                        Damian7546
                        wrote on last edited by Damian7546
                        #23
                        This post is deleted!
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                        • D Offline
                          D Offline
                          Damian7546
                          wrote on last edited by
                          #24
                          This post is deleted!
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                          • jsulmJ jsulm

                            @Damian7546 As all these errors tell you: do the threading properly!

                            D Offline
                            D Offline
                            Damian7546
                            wrote on last edited by
                            #25

                            @jsulm said in Modbus TCP Client write holding registers:

                            @Damian7546 As all these errors tell you: do the threading properly!

                            Can you explain me ?

                            jsulmJ 1 Reply Last reply
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                            • D Damian7546

                              @jsulm said in Modbus TCP Client write holding registers:

                              @Damian7546 As all these errors tell you: do the threading properly!

                              Can you explain me ?

                              jsulmJ Offline
                              jsulmJ Offline
                              jsulm
                              Lifetime Qt Champion
                              wrote on last edited by
                              #26

                              @Damian7546 Look:

                              QObject: Cannot create children for a parent that is in a different thread.
                              (Parent is QModbusTcpClient(0x504f8fc), parent's thread is ClientTicketMach(0x1215a30), current thread is QThread(0x11c0b28)
                              

                              It seems like your QModbusTcpClient is used in different threads. Please analyse your code to see how you're using it.

                              I already mentioned in this thread that threads should only be used if really necessary.

                              https://forum.qt.io/topic/113070/qt-code-of-conduct

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                              • D Offline
                                D Offline
                                Damian7546
                                wrote on last edited by Damian7546
                                #27
                                This post is deleted!
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                                • D Offline
                                  D Offline
                                  Damian7546
                                  wrote on last edited by Damian7546
                                  #28

                                  @jsulm This connect declared in run() function:
                                  connect(this, &ClientTicketMach::holdRegArrayChanged,wr_redy);
                                  run wr_redy in other threadss..:/

                                  Do you have any idea how run wr_redy in my thread by change values in holdRegArray?

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                                  • D Offline
                                    D Offline
                                    Damian7546
                                    wrote on last edited by
                                    #29

                                    @jsulm Now I use Modbus TCP Client without threads and everything works.

                                    1 Reply Last reply
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