QT5 串口收发实例代码

时间:2023-03-08 23:02:33
QT5 串口收发实例代码

以下代码是自己测试门禁系统使用的

主要用到了串口的接收和发送

 开发环境:xp  QT5.1.1

串口:38400   N  8  1

自动检测可用串口

在xp上测试没问题

有些usb转串口会出现波特率不准的问题,CH340的usb转232使用完全正常

以下为收发的线程.h 和.cpp两个文件

最后附上转sacii显示的代码

如果要参考的话,源代码已上传:http://download.csdn.net/detail/liang890319/6463227

#ifndef MYTHREAD_H
#define MYTHREAD_H #include <QThread>
#include <stdio.h>
#include <QtGlobal> class MyThread : public QThread
{
Q_OBJECT
public:
QByteArray requestData;
QByteArray TxData;
MyThread(); void setMessage(const QString &message);
void setPortnum(const QString &num);
void stop();
void startCom();
void changeTxState(bool stat);
void changeRxState(bool stat);
void changeComState(bool stat); signals:
void request(const QString &s);
void comRecive(); protected:
void run(); private:
QString messageStr;
QString portnum;
volatile bool com_opened;
volatile bool stopped;
volatile bool tx_event;
volatile bool rx_event;
}; #endif // MYTHREAD_H
#include "mythread.h"
#include <QtDebug>
//FOR RS232
#include <QtSerialPort/QSerialPort>
#include <QtSerialPort/QSerialPortInfo> MyThread::MyThread()
{
stopped=false; } void MyThread::run()
{
QSerialPort *my_serialport= new QSerialPort; while(!stopped)
{
if(stopped&&com_opened)
{
my_serialport->close();
com_opened=false; }
if(!com_opened)
{
//open com
qDebug() << "Brush:" <<"---open com port------";
com_opened=true;
my_serialport->setPortName(portnum);
my_serialport->open(QIODevice::ReadWrite);
my_serialport->setBaudRate(QSerialPort::Baud38400,QSerialPort::AllDirections);
my_serialport->setDataBits(QSerialPort::Data8);
my_serialport->setParity(QSerialPort::NoParity);
my_serialport->setStopBits(QSerialPort::OneStop);
// my_serialport->setStopBits(QSerialPort::TwoStop);
my_serialport->setFlowControl(QSerialPort::NoFlowControl);
com_opened=true;
}
if(this->com_opened&&this->tx_event)
{
this->tx_event=false;
my_serialport->clear(QSerialPort::AllDirections);
qDebug() << "Brush:" <<"send data to com2"<<this->TxData.length();
qDebug() << "arr size:" <<this->TxData.length();
my_serialport->write(this->TxData);
if (my_serialport->waitForBytesWritten(5))
{
qDebug() << "Brush:" <<"send data success";
if (my_serialport->waitForReadyRead(1500)) //1s
{
requestData = my_serialport->readAll();
while (my_serialport->waitForReadyRead(15))
requestData += my_serialport->readAll();
emit(this->comRecive());
}else
{
qDebug() << "Brush:" <<"wait return time out";
}
}else
{
qDebug() << "Brush:" <<"send time out";
}
}
if (my_serialport->waitForReadyRead(5)) //50ms
{
while (my_serialport->waitForReadyRead(5))
this->msleep(20);
requestData = my_serialport->readAll();
emit(this->comRecive());
}
if(stopped&&com_opened)
{
my_serialport->close();
com_opened=false;
}
}
} void MyThread::stop()
{
stopped=true; }
void MyThread::startCom()
{
stopped=false; }
void MyThread::changeComState(bool stat)
{
com_opened=stat;
}
void MyThread::setMessage(const QString &message)
{
messageStr = message; }
void MyThread::setPortnum(const QString &num)
{
portnum=num; }
void MyThread:: changeTxState(bool stat)
{
tx_event=stat;
}
void MyThread:: changeRxState(bool stat)
{
rx_event=stat;
}

显示部分 比如收到0xff  在text框显示 FF

void MainWindow::displayRxData()
{
QString str;
char tmp[100];
char *buf;
char var;
QDateTime *datatime=new QDateTime(QDateTime::currentDateTime());
if(threadA.requestData.size()>0)
{
str="收到数据: ";
str+=datatime->time().toString();
ui->textEdit_rx->append(str);
str.clear(); buf=threadA.requestData.data();
if(buf[3]==0x01) ui->textEdit_tx->append("加卡成功!");
if(buf[3]==0x02) ui->textEdit_tx->append("删卡成功!");
if(buf[3]==0x03) ui->textEdit_tx->append("开门成功!");
if(buf[3]==0x04) ui->textEdit_tx->append("关门成功!");
qDebug() << "receive num:" <<threadA.requestData.size();
for(var=0;var<threadA.requestData.size();var++)
{
::snprintf(tmp,100, "%02X", (unsigned char)(*buf));
buf++;
str+=QString::fromUtf8(tmp);
str+=" ";
}
ui->textEdit_rx->append(str);
}
threadA.requestData.clear();
}