Qt串口基本设置与协议收发

前言

1.一直都想要做一个Qt上位机，趁着这个周末有时间，动手写一下

2.comboBox没有点击的信号，所以做了一个触发的功能

3.Qt的数据类型很奇怪，转来转去的我也搞得很迷糊

4.给自己挖个坑，下一期做一个查看波形的上位机

有纰漏请指出，转载请说明。

学习交流请发邮件 [e-mail]

串口功能

波特率设置

串口开关

串口异常检测

字符串/HEX收发

定时发送

接收数据分隔

协议组包

协议拆包

源代码

widget.h

#ifndef WIDGET_H
#define WIDGET_H#include <QWidget>
#include <QtSerialPort/QSerialPort>         // 提供访问串口的功能
#include <QtSerialPort/QSerialPortInfo>      // 提供系统中存在的串口信息
#include <QTime>
#include <QtCharts>
#include <QTimer>QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACEclass Widget : public QWidget
{Q_OBJECT//用于表格设置enum FieldColNum {colTime,colCmd1,colCmd2,colData,};enum CellType {ctTime,ctCmd1,ctCmd2,ctData,};
public:int tableRowCnt = 0;
public:Widget(QWidget *parent = nullptr);~Widget();void serialPortInit();  //串口初始化void windowInit();      //显示窗口初始化void refreshCom();      //刷新串口void tableInit();       //表格初始化void createItemsARow(int rowNum, QByteArray *protocalData); //表格新建一行QString ByteArrayToHexString(QByteArray &ba);
private:Ui::Widget *ui;QSerialPort* serialPort;
public slots:void comboBoxClicked(); //comboBox被点击
private slots:void sendData();            //发送串口数据void receiveData();         //接收串口数据void openSerialport();      //串口开启void closeSerialport();     //串口关闭void setBuad(int);          //设置波特率void clearRcv();            //清楚接收缓存void on_btnConvert_clicked();   //转换按钮被点击void on_btnClear_clicked();     //清楚转化的按钮被点击void sendProtocalHexData();     //以hex格式发送串口数据void handleSerialError(QSerialPort::SerialPortError serialPortErr); //串口异常捕获
};#endif // WIDGET_H

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include "newcombobox.h"
#include <algorithm>Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);//创建一个定时器用来定时发送QTimer *timer1 = new QTimer();timer1->start(1000);connect(timer1,&QTimer::timeout,[=](){int timed = ui->comboBox_timedSend->currentText().toInt();timer1->start(timed);if(ui->checkBox_timedSend->isChecked() == true){sendData();}});windowInit();tableInit();serialPort = new QSerialPort();serialPortInit();connect(serialPort,SIGNAL(readyRead()),this,SLOT(receiveData()));connect(serialPort,SIGNAL(errorOccurred(QSerialPort::SerialPortError)),this,SLOT(handleSerialError(QSerialPort::SerialPortError)));connect(ui->pushButton_sendData,SIGNAL(clicked()),this,SLOT(sendData()));connect(ui->pushButton_openSerialPort,SIGNAL(clicked()),this,SLOT(openSerialport()));connect(ui->pushButton_closeSerialPort,SIGNAL(clicked()),this,SLOT(closeSerialport()));connect(ui->comboBox_chooseCom,SIGNAL(clicked()),this,SLOT(comboBoxClicked()));connect(ui->pushButton_clearRcv,SIGNAL(clicked()),this,SLOT(clearRcv()));connect(ui->pushButton_convert,SIGNAL(clicked()),this,SLOT(on_btnConvert_clicked()));connect(ui->pushButton_clearConvertData,SIGNAL(clicked()),this,SLOT(on_btnClear_clicked()));connect(ui->pushButton_sendProtocalData,SIGNAL(clicked()),this,SLOT(sendProtocalHexData()));connect(serialPort,SIGNAL(errorOccurred(QSerialPort::SerialPortError)),this,SLOT(handleSerialError(QSerialPort::SerialPortError)));connect(ui->comboBox_setBuad,SIGNAL(activated(int)),this,SLOT(setBuad(int)));
}Widget::~Widget()
{delete ui;
}//串口异常捕获
void Widget::handleSerialError(QSerialPort::SerialPortError serialPortErr)
{if(serialPortErr == QSerialPort::ResourceError){QMessageBox::critical(NULL, "critical", "设备拔出", QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes);closeSerialport();}if(serialPortErr == QSerialPort::DeviceNotFoundError){QMessageBox::critical(NULL, "critical", "找不到串口", QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes);closeSerialport();}
}void Widget::comboBoxClicked()
{refreshCom();
}void Widget::windowInit()
{ui->pushButton_closeSerialPort->setEnabled(false);ui->pushButton_openSerialPort->setEnabled(false);ui->pushButton_sendData->setEnabled(false);setWindowTitle(tr("串口收发"));ui->comboBox_timedSend->addItem("10");ui->comboBox_timedSend->addItem("100");ui->comboBox_timedSend->addItem("1000");ui->comboBox_timedSend->setCurrentIndex(2);
}void Widget::refreshCom()
{//显示串口列表ui->comboBox_chooseCom->clear();foreach(QSerialPortInfo portInfo, QSerialPortInfo::availablePorts())ui->comboBox_chooseCom->addItem(portInfo.portName()+":"+portInfo.description());ui->pushButton_openSerialPort->setEnabled(ui->comboBox_chooseCom->count()>0);	//
}void Widget::serialPortInit(){refreshCom();ui->comboBox_setBuad->addItem("9600");ui->comboBox_setBuad->addItem("115200");ui->comboBox_setBuad->addItem("921600");ui->comboBox_setBuad->setCurrentIndex(1);}void Widget::tableInit()
{QStringList headerText;headerText<<"时间"<<"命令1"<<"命令2"<<"数据";ui->tableWidget->setColumnCount(headerText.size());      //设置表格列数ui->tableWidget->resizeColumnsToContents();for (int i=0;i<ui->tableWidget->columnCount();i++){QTableWidgetItem *headerItem=new QTableWidgetItem(headerText.at(i));QFont font=headerItem->font();   //获取原有字体设置font.setBold(true);              //设置为粗体font.setPointSize(10);           //字体大小headerItem->setForeground(QBrush(Qt::black));  //设置文字颜色headerItem->setFont(font);       //设置字体ui->tableWidget->setHorizontalHeaderItem(i,headerItem);    //设置表头单元格的item}ui->tableWidget->setColumnWidth(0, 60);ui->tableWidget->setColumnWidth(1, 50);ui->tableWidget->setColumnWidth(2, 50);ui->tableWidget->setColumnWidth(3, 250);
}//为一行的单元格创建 Items
void Widget::createItemsARow(int rowNum, QByteArray *protocalData)
{uchar preFix = 0xA5;uchar crc = 0;uchar temp = 0;temp = static_cast<uchar>(protocalData->at(0));if(static_cast<uchar>(protocalData->at(0)) == preFix){for(int i=1; i<protocalData->length()-2; i++){temp = static_cast<uchar>(protocalData->at(i));crc += static_cast<uchar>(protocalData->at(i));}temp = static_cast<uchar>(protocalData->at(protocalData->length()-2));if(crc != static_cast<uchar>(protocalData->at(protocalData->length()-2))){return;}uchar len = protocalData->at(1);uchar cmd1 = protocalData->at(2);uchar cmd2 = protocalData->at(3);QByteArray data = protocalData->mid(4,len-6);QDateTime curTime = QDateTime::currentDateTime();//获取系统现在的时间QString time = curTime.toString("hh:mm:ss"); //设置显示格式uint8_t str1 = static_cast<uint8_t>(cmd1);QString hexStr1 = QString("%1").arg(str1, 2, 16, QLatin1Char('0')).toUpper();uint8_t str2 = static_cast<uint8_t>(cmd2);QString hexStr2 = QString("%1").arg(str2, 2, 16, QLatin1Char('0')).toUpper();QString testdata = ByteArrayToHexString(data).toLatin1().toUpper();QTableWidgetItem *item = new QTableWidgetItem(time, ctTime);ui->tableWidget->setItem(rowNum, colTime, item);item = new QTableWidgetItem(hexStr1, ctCmd1);ui->tableWidget->setItem(rowNum, colCmd1, item);item = new QTableWidgetItem(hexStr2, ctCmd2);ui->tableWidget->setItem(rowNum, colCmd2, item);item = new QTableWidgetItem(testdata, ctData);ui->tableWidget->setItem(rowNum, colData, item);}auto lastRowIndex = ui->tableWidget->rowCount()-1; // 最后一行的索引auto lastModelIndex = ui->tableWidget->model()->index(lastRowIndex, 0);ui->tableWidget->scrollTo(lastModelIndex);         // 滚动到最后一行
}QString Widget::ByteArrayToHexString(QByteArray &ba)
{QDataStream out(&ba,QIODevice::ReadWrite);   //将str的数据 读到out里面去QString buf;while(!out.atEnd()){qint8 outChar = 0;out >> outChar;   //每次一个字节的填充到 outcharQString str = QString("%1").arg(outChar&0xFF,2,16,QLatin1Char('0')).toUpper() + QString(" ");   //2 字符宽度buf += str;}return buf;
}void Widget::sendData()
{QString message = ui->lineEdit_sendData->text();if(ui->checkBox_hexSend->isChecked() == true){serialPort->write(QByteArray::fromHex(message.toLatin1()));}else{serialPort->write(message.toLatin1());}
}void Widget::receiveData()
{QByteArray message;QString hexMsg;message.append(serialPort->readAll());QDateTime time = QDateTime::currentDateTime();  //获取系统现在的时间QString date = time.toString("hh:mm:ss");       //设置显示格式if(ui->checkBox_hexRcv->isChecked() == true){tableRowCnt++;ui->tableWidget->setRowCount(tableRowCnt);createItemsARow(tableRowCnt-1,&message);hexMsg = ByteArrayToHexString(message).toLatin1();ui->textEdit_RecData->append(date+QString("->  ")+hexMsg.toUpper());}else{ui->textEdit_RecData->append(date+QString("->  ")+message);}
}
void Widget::openSerialport()
{ui->pushButton_closeSerialPort->setEnabled(true);ui->pushButton_openSerialPort->setEnabled(false);QList<QSerialPortInfo>  comList = QSerialPortInfo::availablePorts();QSerialPortInfo portInfo = comList.at(ui->comboBox_chooseCom->currentIndex());serialPort->setPort(portInfo);      //设置使用哪个串口if(serialPort->open(QIODevice::ReadWrite) == false){QMessageBox::critical(NULL, "critical", "找不到串口/串口被占用", QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes);closeSerialport();}else{serialPort->setBaudRate(QSerialPort::Baud115200);serialPort->setDataBits(QSerialPort::Data8);serialPort->setParity(QSerialPort::NoParity);serialPort->setStopBits(QSerialPort::OneStop);serialPort->setFlowControl(QSerialPort::NoFlowControl);ui->pushButton_sendData->setEnabled(true);}
}void Widget::closeSerialport()
{if(serialPort->isOpen()){serialPort->clear();serialPort->close();}ui->pushButton_closeSerialPort->setEnabled(false);ui->pushButton_openSerialPort->setEnabled(true);
}void Widget::setBuad(int buad)
{QString str = ui->comboBox_setBuad->currentText();serialPort->setBaudRate(str.toInt());
}void Widget::clearRcv()
{ui->textEdit_RecData->clear();
}void Widget::on_btnClear_clicked()
{ui->lineEdit_protocalData->clear();
}void Widget::on_btnConvert_clicked()
{ui->lineEdit_protocalData->clear();bool ok;QString str = "A5";int val1= ui->lineEditCmd1->text().toInt(&ok,16);  //以十六进制数读入QString str1 = QString("%1").arg(val1, 2, 16, QLatin1Char('0'));int val2= ui->lineEditCmd2->text().toInt(&ok,16);  //以十六进制数读入QString str2 = QString("%1").arg(val2, 2, 16, QLatin1Char('0'));if ((str1.isEmpty())||(str2.isEmpty()))return;int val3= ui->lineEditData->text().toInt(&ok,16);  //以十六进制数读入QString str3 = QString("%1").arg(val3, 2, 16, QLatin1Char('0'));uint8_t len = 6 + static_cast<uint8_t>(str3.length()/2);QString hexStr = QString("%1").arg(len, 2, 16, QLatin1Char('0'));str.append(hexStr);str.append(str1);str.append(str2);str.append(str3);uint8_t crc;QString tmp;for(int i=0; i<str3.length(); i+=2){tmp = ui->lineEditData->text()[i];tmp += ui->lineEditData->text()[i+1];crc+= tmp.toInt(&ok,16);tmp = "";}crc += len;crc += val1;crc += val2;QString hexCrc= QString("%1").arg(crc, 2, 16, QLatin1Char('0'));str.append(hexCrc);str.append("5A");str = str.toUpper();ui->lineEdit_protocalData->insert(str);
}void Widget::sendProtocalHexData()
{QString message = ui->lineEdit_protocalData->text();serialPort->write(QByteArray::fromHex(message.toLatin1()));
}

ui

代码框架概览

演示视频

串口上位机(基本设置/协议收发)演示_哔哩哔哩_bilibili

串口上位机(基本设置/协议收发)演示