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How to open more than once SerialPort

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  • mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by
    #7

    Hi
    In void MainWindow::closeSerialPort()
    you call if (serialPort->isOpen())

    But that is only serialPort pointer. you are not using the
    Vector<QSerialPort *> v; at all so i wonder if this is what u want ?

    I imagine you need to loop over v and close all and not just whatever
    serialPort points to ?

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    0
    • E Offline
      E Offline
      erytcg
      wrote on last edited by
      #8

      I don't understand good with this QVector. I don't know how acces to one of port and close one port not all.

      mrjjM 1 Reply Last reply
      0
      • E erytcg

        I don't understand good with this QVector. I don't know how acces to one of port and close one port not all.

        mrjjM Offline
        mrjjM Offline
        mrjj
        Lifetime Qt Champion
        wrote on last edited by mrjj
        #9

        @erytcg
        Hi
        its a list of comports.

        so v[index] gives a QSerialPort *

        But you will have to answer what app does.

        Currently you open all comports available on device.

        Should closeSerialPort() close them all again?

        to close one you would do
        QSerialPort * Cur=v[0];
        Cur->close();
        or even
        v[0]->close();

        Notice i use 0 for closing the first.

        So to help you , i need to understand what app does as its uncommon to open ALL comports :)

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        • E Offline
          E Offline
          erytcg
          wrote on last edited by
          #10

          So I need more functions, one for add aviable ports to vector and one to open specific port? For close functions I want close only one port.

          mrjjM 1 Reply Last reply
          0
          • E erytcg

            So I need more functions, one for add aviable ports to vector and one to open specific port? For close functions I want close only one port.

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #11

            @erytcg

            • close functions I want close only one port.

            But which one?

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            • E Offline
              E Offline
              erytcg
              wrote on last edited by
              #12

              Choosing from:
              QList<QListWidgetItem*> items = ui->listWidget->selectedItems();
              foreach(QListWidgetItem * item, items)
              {
              delete ui->listWidget->takeItem(ui->listWidget->row(item));
              }

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              • mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by mrjj
                #13

                Hi
                if you move
                QVector<QSerialPort *> v;
                to the MainWindow.h (in the class)
                and remove serialPort variable also!

                then you could do

                void MainWindow::closeSerialPort( int index)
                {
                QSerialPort * serialPort = v[index];
                if (serialPort->isOpen())
                {
                serialPort->close();
                ..

                and close the one u want with
                closeSerialPort( some number)

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                • mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by
                  #14

                  Oh u posted while i was writing

                  Can you use the row index directly to the V list ?

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                  • E Offline
                    E Offline
                    erytcg
                    wrote on last edited by
                    #15

                    yes I want to add opened COMports to ListWidget and close selected ports

                    mrjjM 1 Reply Last reply
                    0
                    • E erytcg

                      yes I want to add opened COMports to ListWidget and close selected ports

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #16

                      @erytcg

                      If there is a 1 to 1 to the V list ( please rename to comports or something :)

                      Then you can just use the
                      void MainWindow::closeSerialPort( int index)
                      {
                      QSerialPort * serialPort = v[index];
                      ...

                      and call it from
                      foreach(QListWidgetItem * item, items) {
                      int index= ui->listWidget->row(item); //
                      closeSerialPort( index);

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                      • E Offline
                        E Offline
                        erytcg
                        wrote on last edited by
                        #17

                        Hey can you look at code? Now it's ok? :)

                        void MainWindow::addAvailableSerialPorts()
                        {
                            QVector<QSerialPort *> v;
                            Q_FOREACH(QSerialPortInfo port, QSerialPortInfo::availablePorts())
                                {
                                   QSerialPort* serialPort = new QSerialPort();
                                   serialPort->setPort(port);
                                   serialPort->setBaudRate(QSerialPort::Baud9600);
                                   serialPort->setDataBits(QSerialPort::Data8);
                                   serialPort->setParity(QSerialPort::NoParity);
                                   serialPort->setStopBits(QSerialPort::OneStop);
                                   serialPort->setFlowControl(QSerialPort::NoFlowControl);
                                   v.append(serialPort);
                                }
                        }
                        void MainWindow::openSerialPort(int index)
                        {         
                            QSerialPort * serialPort = v[index];
                            if (serialPort->open(QIODevice::ReadWrite)) 
                             {
                                 showStatusMessage(tr("Connected to %1 : OK").arg(p.name));
                             } 
                            else 
                            {
                                 QMessageBox::critical(this, tr("Error"), serialPort->errorString());
                                 showStatusMessage(tr("Open error"));
                            }
                        }
                        
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                        • mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by mrjj
                          #18

                          @erytcg said in How to open more than once SerialPort:

                          Almost but one fatal error !

                          void MainWindow::addAvailableSerialPorts()
                          {
                          QVector<QSerialPort *> v; <<<< This is a local var. It should be in class. windows .h. should not be defined here. only used.

                          So in
                          void MainWindow::openSerialPort(int index)
                          {
                          QSerialPort * serialPort = v[index]; <<< what v is this . it cannot be the one from addAvailableSerialPorts as that was local.

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                          1
                          • E Offline
                            E Offline
                            erytcg
                            wrote on last edited by
                            #19

                            ok I add *QVector<QSerialPort > v; to private: mainwindow.h
                            I have problem with close function port chooseing from list widget

                            mrjjM 1 Reply Last reply
                            0
                            • E erytcg

                              ok I add *QVector<QSerialPort > v; to private: mainwindow.h
                              I have problem with close function port chooseing from list widget

                              mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on last edited by
                              #20

                              @erytcg

                              you need to use the row int as index

                              foreach(QListWidgetItem * item, items) {
                              int index= ui->listWidget->row(item); //
                              closeSerialPort( index);
                              
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                              • E Offline
                                E Offline
                                erytcg
                                wrote on last edited by
                                #21

                                Hey it's good idea to recall to function

                                void MainWindow::on_connectAction_clicked()
                                {
                                    openSerialPort(ui->serialPortInfoListBox->currentIndex());
                                }
                                

                                I think it's not MVC

                                mrjjM 1 Reply Last reply
                                0
                                • E erytcg

                                  Hey it's good idea to recall to function

                                  void MainWindow::on_connectAction_clicked()
                                  {
                                      openSerialPort(ui->serialPortInfoListBox->currentIndex());
                                  }
                                  

                                  I think it's not MVC

                                  mrjjM Offline
                                  mrjjM Offline
                                  mrjj
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #22

                                  @erytcg
                                  Hi
                                  Im not sure what you talk about.
                                  MVC= model, view , controller?

                                  Is there a question ?

                                  What you mean recall ?
                                  Do you open it in addAvailableSerialPorts ?

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                                  0
                                  • E Offline
                                    E Offline
                                    erytcg
                                    wrote on last edited by
                                    #23

                                    Yes I talk about model, view , controller.
                                    I add all avaibleports to vector in addAvailableSerialPorts ()
                                    i open in openSerialPort(int index) / index=QComboBox->currentIndex();
                                    and close in closeSerialPort(int index) / index=QListWidget->currentRow()+1;

                                    and all works fine I think, but if I want show received data on QCustomPlot widget.
                                    I don't know how to convert QByteArray to QVector<double>.
                                    My received data from qDebug() - "\x0B"
                                    Thanks a lot for help :)

                                    mrjjM 1 Reply Last reply
                                    0
                                    • E erytcg

                                      Yes I talk about model, view , controller.
                                      I add all avaibleports to vector in addAvailableSerialPorts ()
                                      i open in openSerialPort(int index) / index=QComboBox->currentIndex();
                                      and close in closeSerialPort(int index) / index=QListWidget->currentRow()+1;

                                      and all works fine I think, but if I want show received data on QCustomPlot widget.
                                      I don't know how to convert QByteArray to QVector<double>.
                                      My received data from qDebug() - "\x0B"
                                      Thanks a lot for help :)

                                      mrjjM Offline
                                      mrjjM Offline
                                      mrjj
                                      Lifetime Qt Champion
                                      wrote on last edited by mrjj
                                      #24

                                      @erytcg
                                      Nope a list of Class * is not really MVC.

                                      Do you really need to convert QByteArray to QVector<double> ?
                                      Why not convert to doubles when you read and add directly to QVector instead?

                                      Also who sends the doubles? Its not trivial to send doubles over serial as they dont map
                                      nicely to chars and there can be a difference in byteorder and precision loss.

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                                      • E Offline
                                        E Offline
                                        erytcg
                                        wrote on last edited by erytcg
                                        #25

                                        I need convert because QCustomPlot func need doubles

                                        void 	addData (const QVector< double > &keys, const QVector< double > &values, bool alreadySorted=false)
                                        or
                                        void 	addData (double key, double value)
                                        
                                        mrjjM 1 Reply Last reply
                                        0
                                        • E erytcg

                                          I need convert because QCustomPlot func need doubles

                                          void 	addData (const QVector< double > &keys, const QVector< double > &values, bool alreadySorted=false)
                                          or
                                          void 	addData (double key, double value)
                                          
                                          mrjjM Offline
                                          mrjjM Offline
                                          mrjj
                                          Lifetime Qt Champion
                                          wrote on last edited by mrjj
                                          #26

                                          @erytcg
                                          Yes, i understand CustomPlot wants QVector<double> but i was wondering
                                          instead of storing all values in ByteArray and then convert, if it would be more easy
                                          to store directly in QVector when reading them off the serial port.

                                          Anyway, how do u know how many indexes one double will take in ByteArray ?
                                          double is normally 8 bytes (32 bit). Do you know the byte order from the sender?

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