THECODEPROGRAM

Now let's get started.

QT += serialport

Now we are ready to use QSerialPort Class in QT C++.

We shall add following class in head of header file of our class.

#include <QtSerialPort/QSerialPort>

private:
    QSerialPort *serial;

Now we can use the serial port in our program. Lets write some more codes. Open the .cpp file write below functions.

void MainWindow::fnc_openSerialPort()
{
    serial->setPortName("COM1");
    serial->setBaudRate(9600);
    serial->setDataBits(QSerialPort::DataBits);
    //We will chose the parity bits
    serial->setParity(QSerialPort::Parity);
    //We will chose the stop bits
    serial->setStopBits(QSerialPort::StopBits);
    //We will chose the Flow controls
    serial->setFlowControl(QSerialPort::FlowControl);
    if (serial->open(QIODevice::ReadWrite)) {

    } else {
        QMessageBox::critical(this, tr("Error"), serial->errorString());
    }
}

This is the code block to open COM1 serial Port with 9600 BaudRate and the other values.

void MainWindow::fnc_closeSerialPort()
{
     if (serial->isOpen())
             serial->close();
}

To write data on Serial Port via opened COM port first we need to check the port is opened and avail to write some data. we have to write the data with ASCII values.

void MainWindow::writeData()
{
    if(serial->isOpen())
            serial->write(ui->txtSerialSendData->text().toLatin1() );
    else
        QMessageBox::critical(this, tr("Write Error"), serial->errorString());
}

if(serial->isOpen())
   serial->write(ui->txtSerialSendData->text().toLatin1() + char(13)  );
else
   serial->write(ui->txtSerialSendData->text().toLatin1() );

And also we need to read datas on Serial Port. We can do it with below code block.

void MainWindow::readData()
{
    bool _ok;
    //This code is to read all data on serial port
    QByteArray data = serial->readAll();
    if (ui->chkGetHexadecimalValue->isChecked() == true)
        qDebug() << data.toHex();  //Here is the read data as Hex values
    else
        qDebug() << data;  // Here is the code block to read normal latin words.
}

Now we can use the serial port with our QT GUI C++ program.

That is all for this article.

Have a good communication.

Burak hamdi TUFAN