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How to open more than once SerialPort

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  • E Offline
    E Offline
    erytcg
    wrote on last edited by
    #6
    void MainWindow::openSerialPort()
    {         
        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);
    
                if (serialPort->open(QIODevice::ReadWrite)) {
                     v.append(serialPort);
                     ui->listWidget->addItem(p.name);
                  
                } else { 
                    QMessageBox::critical(this, tr("Error"), serialPort->errorString());
    
                    showStatusMessage(tr("Open error"));
                }
            }
    
    }
    
    void MainWindow::closeSerialPort()
    {
        if (serialPort->isOpen())
        {
            serialPort->close();
            QList<QListWidgetItem*> items = ui->listWidget->selectedItems();
            foreach(QListWidgetItem * item, items)
            {
                delete ui->listWidget->takeItem(ui->listWidget->row(item));
            }
        }
    
        showStatusMessage(tr("Disconnected"));
    }
    

    it's ok?

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    0
    • 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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          0
          • 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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                0
                • 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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                    0
                    • 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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                        1
                        • 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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                                    • 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.

                                        1 Reply Last reply
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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
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