QT programming serial port assistant

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QT Write serial port assistant

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1.pro File adding serialport

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2.widget.h Documentation

#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
#include <QSerialPort>        // Provides the function of accessing the serial port 
#include <QSerialPortInfo>    // Provide the information of the serial port in the system 

namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
    void set_baudList();  // Set baud rate option 
    void set_parityList();// Set check bit options 
    void set_dataBitsList();// Set data bit options 
    void set_stopBitsList();// Set the stop bit option 
    void serial_Init();// Serial port setting initialization 

private slots:
    void on_pushButton_2_clicked();
    void on_pushButton_clicked();
    void serialPort_readyRead();
    void on_pushButton_3_clicked();
    void on_pushButton_5_clicked();

private:
    Ui::Widget *ui;
    QSerialPort serial;
};
#endif // WIDGET_H

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3.main.cpp Documentation

#include "widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();

    return a.exec();
}

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4.widget.cpp Documentation

#include "widget.h"
#include "ui_widget.h"
#include <QMessageBox>
#include <QString>
#include <iostream>

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
       ui->setupUi(this);
       ui->comboBox->clear();
       this->setWindowTitle(" Serial assistant ");

    // Set window fixed size 
       this->setMaximumSize(800,550);
       this->setMinimumSize(800,550);

    // adopt QSerialPortInfo Find available serial ports 
       foreach(const QSerialPortInfo &info, QSerialPortInfo::availablePorts())
       {
           ui->comboBox->addItem(info.portName());
       }
    // Connecting signals and slots 
       QObject::connect(&serial, &QSerialPort::readyRead, this, &Widget::serialPort_readyRead);

    // Serial port setting initialization 
       serial_Init();



}

Widget::~Widget()
{
    delete ui;
}

// Set baud rate option function **********************************************
void Widget::set_baudList()
{
    QStringList baudList; // Baud rate object 
    baudList<<"1200"<<"2400"<<"4800"<<"9600"
               <<"14400"<<"19200"<<"38400"<<"56000"
               <<"57600"<<"115200";
    ui->comboBox_2->addItems(baudList);
    ui->comboBox_2->setCurrentIndex(3);
}

// Set check bit function **********************************************
void Widget::set_parityList()
{
     QStringList parityList; // Check bit object 
     parityList<<" nothing "<<" Odd check "<<" Even check ";
     ui->comboBox_5->addItems(parityList);
     ui->comboBox_5->setCurrentIndex(0);
}

// Set the data bit function **********************************************
void Widget::set_dataBitsList()
{
    QStringList dataBitsList;   // Data bit object 
    dataBitsList<<"5"<<"6"<<"7"<<"8";
    ui->comboBox_4->addItems(dataBitsList);
    ui->comboBox_4->setCurrentIndex(3);
}

// Set stop bit function **********************************************
void Widget::set_stopBitsList()
{
     QStringList stopBitsList;   // Stop bit object 
     stopBitsList<<"1"<<"2";
     ui->comboBox_3->addItems(stopBitsList);
     ui->comboBox_3->setCurrentIndex(0);
}

// Serial port setting initialization function *********************************************
void Widget::serial_Init()
{
    // Set baud rate options 
    set_baudList();
    // Set check bit options 
    set_parityList();
    // Set data bit options 
    set_dataBitsList();
    // Set the stop bit option 
    set_stopBitsList();

}

// Detect serial port slot function *****************************************************
void Widget::on_pushButton_2_clicked()
{
        ui->comboBox->clear();
        // adopt QSerialPortInfo Find available serial ports 
        foreach(const QSerialPortInfo &info, QSerialPortInfo::availablePorts())
        {
            ui->comboBox->addItem(info.portName());
        }
}

// Open the serial slot function ****************************************************
void Widget::on_pushButton_clicked()
{
    if(ui->pushButton->text()==QString(" Open the serial port "))
    {
       // Set serial port name 
      serial.setPortName(ui->comboBox->currentText());
      // set baud rate 
      serial.setBaudRate(ui->comboBox_2->currentText().toInt());
      // set data bit 
      switch(ui->comboBox_4->currentIndex())
            {
             case 5: serial.setDataBits(QSerialPort::Data5); break;
             case 6: serial.setDataBits(QSerialPort::Data6); break;
             case 7: serial.setDataBits(QSerialPort::Data7); break;
             case 8: serial.setDataBits(QSerialPort::Data8); break;
             default: break;
                  }
      // Set parity 
      switch(ui->comboBox_5->currentIndex())
            {
             case 0: serial.setParity(QSerialPort::NoParity); break;
             case 1: serial.setParity(QSerialPort::OddParity); break;
             case 2: serial.setParity(QSerialPort::EvenParity); break;
             default: break;
                  }
      //  set flow control 
      serial.setFlowControl(QSerialPort::NoFlowControl);
      // Set stop bit 
      switch(ui->comboBox_3->currentIndex())
            {
             case 1: serial.setStopBits(QSerialPort::OneStop); break;
             case 2: serial.setStopBits(QSerialPort::TwoStop); break;
             default: break;
                  }
      // Open the serial port 
      if(!serial.open(QIODevice::ReadWrite))
              {
                  QMessageBox::about(NULL, " Tips ", " Unable to open serial port ！");
                  return;
              }
      // The drop-down menu control fails 
      ui->comboBox->setEnabled(false);
      ui->comboBox_2->setEnabled(false);
      ui->comboBox_3->setEnabled(false);
      ui->comboBox_4->setEnabled(false);
      ui->comboBox_5->setEnabled(false);

      // Send key enable 
      ui->pushButton->setEnabled(true);


    }
    else
    {
        serial.close();
        // Pull down the key to enable 
        ui->comboBox->setEnabled(true);
        ui->comboBox_2->setEnabled(true);
        ui->comboBox_3->setEnabled(true);
        ui->comboBox_4->setEnabled(true);
        ui->comboBox_5->setEnabled(true);
        // Search serial port key enable 
        ui->pushButton_2->setEnabled(true);
        // Send key enable 
        ui->pushButton->setEnabled(false);

      }

}

// The receiving window displays the slot function *************************************************
void Widget::serialPort_readyRead()
{
    // Read data from receive buffer 
       QByteArray buffer = serial.readAll();
       // Read the previously received data from the interface 
       QString recv = ui->textBrowser->toPlainText();
       recv += QString(buffer);
       // Clear the previous display 
       ui->textBrowser->clear();
       // To display 
       ui->textBrowser->append(recv);
}

// Clear the slot function of the display window *********************************************
void Widget::on_pushButton_3_clicked()
{

    ui->textBrowser->clear();
}

// Close the serial slot function *********************************************
void Widget::on_pushButton_5_clicked()
{
    serial.close();
    // Pull down the key to enable 
    ui->comboBox->setEnabled(true);
    ui->comboBox_2->setEnabled(true);
    ui->comboBox_3->setEnabled(true);
    ui->comboBox_4->setEnabled(true);
    ui->comboBox_5->setEnabled(true);
    // Search serial port key enable 
    ui->pushButton_2->setEnabled(true);
    // Send key enable 
    ui->pushButton->setEnabled(true);
}

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5. Effect display

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