QT串口通訊編程

QT串口編程

文件夾目錄結構以下圖所示

設計的示例界面以下圖所示

首先在項目文件裏面添加一句

QT       += serialport

SerialPortDemo.pro文件以下:

#-------------------------------------------------
#
# Project created by QtCreator 2019-02-21T13:23:59
#
#-------------------------------------------------

QT   += core gui
QT   += serialport

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = SerialPortDemo
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000# disables all the APIs deprecated before Qt 6.0.0

CONFIG += c++11

SOURCES += \
main.cpp \
mainwindow.cpp

HEADERS += \
mainwindow.h

FORMS += \
mainwindow.ui

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

在頭文件mainwindow.h中引入qt串口通訊所須要的頭文件，mainwindow.h文件代碼以下：

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QDebug>

//引入qt中串口通訊須要的頭文件
#include <QtSerialPort/QSerialPort>
#include <QtSerialPort/QSerialPortInfo>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
Q_OBJECT

public:
explicit MainWindow(QWidget *parent = nullptr);
~MainWindow();

private slots:
void on_OpenSerialButton_clicked();

void ReadData();

void on_btnSend_clicked();

private:
Ui::MainWindow *ui;

QSerialPort *serial;//全局的串口對象

};

#endif // MAINWINDOW_H
##實現效果的mainwindow.cpp代碼以下：
#include "mainwindow.h"
#include "ui_mainwindow.h"

//添加串口通訊須要用到的兩個串口頭文件
#include "QtSerialPort/QSerialPort"
#include "QtSerialPort/QSerialPortInfo"

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);

//查找可用的串口
foreach(const QSerialPortInfo &info,QSerialPortInfo::availablePorts())
{
QSerialPort serial;
serial.setPort(info);
if(serial.open(QIODevice::ReadWrite))
{
ui->portBox->addItem(serial.portName());
serial.close();
}
}

//設置波特率下拉菜單的第0項默認值
ui->baudBox->setCurrentIndex(0);
}

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

void MainWindow::on_OpenSerialButton_clicked()
{
if(ui->OpenSerialButton->text()==tr("打開串口"))
{
 serial=new QSerialPort;
 //設置串口名
 serial->setPortName(ui->portBox->currentText());
 //打開串口
 serial->open(QIODevice::ReadWrite);
 //設置波特率
 serial->setBaudRate(QSerialPort::Baud115200);
 //設置數據爲
 switch(ui->dataBox->currentIndex())
 {
 case 0:
 serial->setDataBits(QSerialPort::Data8);
 break;
 default:
 break;
 }
 //設置校驗位
 switch (ui->checkBox->currentIndex())
 {
 case 0:
 serial->setParity(QSerialPort::NoParity);
 break;
 default:
 break;
 }
 //設置中止爲
 switch(ui->stopBox->currentIndex())
 {
 case 0:
 serial->setStopBits(QSerialPort::OneStop);
 break;
 case 1:
 serial->setStopBits(QSerialPort::TwoStop);
 break;
 default:
 break;
 }
 //設置流控制
 serial->setFlowControl(QSerialPort::NoFlowControl);//設置爲無流控制

 //關閉設置菜單使能
 ui->portBox->setEnabled(false);
 ui->dataBox->setEnabled(false);
 ui->checkBox->setEnabled(false);
 ui->stopBox->setEnabled(false);
 ui->baudBox->setEnabled(false);
 ui->OpenSerialButton->setText("關閉串口");


 QObject::connect(serial,&QSerialPort::readyRead,this,&MainWindow::ReadData);
}
else
{
//關閉串口
serial->clear();
serial->close();
serial->deleteLater();

//恢復使能
ui->portBox->setEnabled(true);
ui->baudBox->setEnabled(true);
ui->dataBox->setEnabled(true);
ui->checkBox->setEnabled(true);
ui->stopBox->setEnabled(true);
ui->OpenSerialButton->setText("打開串口");
}

}


void MainWindow::on_btnSend_clicked()
{
serial->write(ui->txtWrite->toPlainText().toLatin1());
}

//讀取接收到的消息
void MainWindow::ReadData()
{
QByteArray buf;

buf=serial->readAll();
if(!buf.isEmpty())
{
QString str = buf;
ui->txtRead->appendPlainText(str);
}
buf.clear();
}

最終運行效果以下圖所示：