Qt串行端口 - 一致地读取数据

Ale*_*ren 6 c++ qt serial-port qtserialport

我通过串口向设备发送(写入)字节.我正在使用QSerialPort(http://qt-project.org/wiki/QtSerialPort)模块来实例化设备IO支持.当我向INSTEON调制解调器(串行)发送消息时,在读取我的消息时,设备会发回我的消息副本+ 0x06(ACK Byte),然后是状态消息.

我使用DockLight(http://www.docklight.de/)测试了我的消息.我发送以下消息来查询设备的状态:

    02 62 1D E9 4B 05 19 00
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使用Docklight,我收到回复:

    02 62 1D E9 4B 05 19 00 06 02 50 20 CB CF 1E DA F7 21 00 FF
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返回的消息准确表明了我期望的设备是什么.如果关闭,如果设备关闭,调制解调器将在最后一个字节位置发回0x00.现在,我的问题 - 我必须正确设置我的功能才能发送然后接收响应字节.我尝试了很多不同的示例和配置,目前我正在使用以下内容:

设置信号槽连接:

QObject::connect(&thread, SIGNAL(sendResponse(QByteArray)), 
    this, SLOT(handleResponse(QByteArray)));
QObject::connect(&thread, SIGNAL(error(QString)), 
    this, SLOT(processError(QString)));
QObject::connect(&thread, SIGNAL(timeout(QString)), 
    this, SLOT(processTimeout(QString)));
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用于迭代设备QList的函数.如果设备是所需类型("Light"),那么我们将设备ID格式化为预期的QByteArray消息结构.将消息传递给线程以进行发送.(从QSerialPort BlockingMaster示例修改的线程.

void Device::currentStatus(QList<Device *> * deviceList){
    QString devID, updateQry;
    int devStatus, updateStatus;
    updateStatus=0;
    QSqlQuery query;
    for(int i=0; i<deviceList->size(); i++){
        if(deviceList->at(i)->type == "Light"){
            devStatus = deviceList->at(i)->status;
            devID = deviceList->at(i)->deviceID;
            QByteArray msg;
            bool msgStatus;
            msg.resize(8);

            msg[0] = 0x02;
            msg[1] = 0x62;
            msg[2] = 0x00;
            msg[3] = 0x00;
            msg[4] = 0x00;
            msg[5] = 0x05;
            msg[6] = 0x19;
            msg[7] = 0x00;
            msg.replace(2, 3, QByteArray::fromHex( devID.toLocal8Bit() ) );
            qDebug() << "Has device " << deviceList->at(i)->name << "Changed?";
            //send(msg,&msgStatus, &updateStatus);
            //msg.clear();
            thread.setupPort("COM3",500,msg);
            if(devStatus!=updateStatus){
                qDebug() << deviceList->at(i)->name << " is now: " << updateStatus;
                updateStatus = !updateStatus;
            }
        }
    }
}
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SetupThread 函数用于设置本地线程变量并执行(运行)线程.

void serialThread::setupPort(const QString &portName, int waitTimeout, const QByteArray &msg){
    qDebug() << "Send Message " << msg.toHex();
    QMutexLocker locker(&mutex);
    this->portName = portName;
    this->waitTimeout = waitTimeout;
    this->msg = msg;
    if(!isRunning())
        start();
    else
        cond.wakeOne();
}
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Run 功能 - 处理发送和接收

void serialThread::run(){
    bool currentPortNameChanged = false;
    qDebug() << "Thread executed";
    mutex.lock();
    QString currentPortName;
    if(currentPortName != portName){
        currentPortName = portName;
        currentPortNameChanged = true;
    }

    int currentWaitTimeout = waitTimeout;
    QByteArray sendMsg = msg;
    mutex.unlock();
    QSerialPort serial;

    while(!quit){
        if(currentPortNameChanged){
            serial.close();
            serial.setPortName("COM3");

            if (!serial.open(QIODevice::ReadWrite)) {
                emit error(tr("Can't open %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }

            if (!serial.setBaudRate(QSerialPort::Baud19200)) {
                emit error(tr("Can't set baud rate 9600 baud to port %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }

            if (!serial.setDataBits(QSerialPort::Data8)) {
                emit error(tr("Can't set 8 data bits to port %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }

            if (!serial.setParity(QSerialPort::NoParity)) {
                emit error(tr("Can't set no patity to port %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }

            if (!serial.setStopBits(QSerialPort::OneStop)) {
                emit error(tr("Can't set 1 stop bit to port %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }

            if (!serial.setFlowControl(QSerialPort::NoFlowControl)) {
                emit error(tr("Can't set no flow control to port %1, error code %2")
                           .arg(portName).arg(serial.error()));
                return;
            }
        }

        //write request
        serial.write(msg);
        if (serial.waitForBytesWritten(waitTimeout)) {
            //! [8] //! [10]
            // read response
            if (serial.waitForReadyRead(currentWaitTimeout)) {
                QByteArray responseData = serial.readAll();
                while (serial.waitForReadyRead(10)){
                    responseData += serial.readAll();
                }

                QByteArray response = responseData;
                //! [12]
                emit this->sendResponse(response);
                //! [10] //! [11] //! [12]
            } else {
                emit this->timeout(tr("Wait read response timeout %1")
                             .arg(QTime::currentTime().toString()));
            }
            //! [9] //! [11]
        } else {
            emit timeout(tr("Wait write request timeout %1")
                         .arg(QTime::currentTime().toString()));
        }
        mutex.lock();
        cond.wait(&mutex);
        if (currentPortName != portName) {
            currentPortName = portName;
            currentPortNameChanged = true;
        } else {
            currentPortNameChanged = false;
        }
        currentWaitTimeout = waitTimeout;
        sendMsg = msg;
        mutex.unlock();
    }
    serial.close();
}
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handleResponse 功能,接收响应信号的SLOT

void Device::handleResponse(const QByteArray &msg){
    qDebug() << "Read: " << msg.toHex();
}
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我收到以下输出:

Has device  "Living Room Light" Changed? 
Send Message  "02621de94b051900" 
Has device  "Bedroom Light" Changed? 
Send Message  "026220cbcf051900" 
Thread executed 
Read:  "026220cbcf05190006" 
Polling for changes... 
Has device  "Living Room Light" Changed? 
Send Message  "02621de94b051900" 
Has device  "Bedroom Light" Changed? 
Send Message  "026220cbcf051900" 
Read:  "025020cbcf1edaf721000002621de94b05190006" 
Polling for changes... 
Has device  "Living Room Light" Changed? 
Send Message  "02621de94b051900" 
Has device  "Bedroom Light" Changed? 
Send Message  "026220cbcf051900" 
Read:  "02501de94b1edaf72100ff02621de94b05190006" 
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这里有两个问题.

  1. 我从未收到有关第二个设备(卧室灯)的任何回复,这是第二个发送的消息.似乎发送被阻止,你会如何建议我格式化我的发送,以便在收到第一次发送的响应后发送?只有1个COM端口可用于发送/接收.我相信我应该发送消息到设备1,接收设备1响应,发送到设备2,接收设备2.我最终会看到很多设备和使用等待条件的巨大交通堵塞,即.在执行设备2的通信过程之前,等待设备1通信过程完成?

  2. 第一次读取包含适当的前半部分接收.Read: "026220cbcf05190006"第二个接收包含第一个响应的后半部分,然后是第二个响应的前半部分:读取2 - Read: "025020cbcf1edaf721000002621de94b05190006"相应的完整响应是02621DE94B05190006 025020CBCF1EDAF72100FF (注意20CBCF完整响应示例中的设备2的ID)

我应该对从串口接收数据的方式进行哪些更正?谢谢!

Ale*_*ren 3

我相信我的问题已经超出了这个问题的范围。在 Kuzulis 的帮助下,我实现了写入/读取功能,以成功地一致地发送和读取串行消息。Kuzulis 建议使用同步阻塞通信模式,但后来决定异步非阻塞方法最适合我的应用程序。

我的实现紧密遵循 QSerialPort 源文件提供的“Master”示例。

我用来CurrentStatus迭代Device对象的 QList。对于设备列表中的每个灯,我格式化一个 8 字节消息来查询设备的当前状态(开/关)。

void Device::currentStatus(QList<Device *> * deviceList){
    QString devID, updateQry;
    int devStatus, updateStatus;
    updateStatus=0;
    QSqlQuery query;
    for(int i=0; i<deviceList->size(); i++){
        if(deviceList->at(i)->type == "Light"){
            devStatus = deviceList->at(i)->status;
            devID = deviceList->at(i)->deviceID;
            QByteArray msg;
            msg.resize(8);

            msg[0] = 0x02;
            msg[1] = 0x62;
            msg[2] = 0x00;
            msg[3] = 0x00;
            msg[4] = 0x00;
            msg[5] = 0x05;
            msg[6] = 0x19;
            msg[7] = 0x00;
            msg.replace(2, 3, QByteArray::fromHex( devID.toLocal8Bit() ) );
            qDebug() << "Has device " << deviceList->at(i)->name << "Changed?";

            emit writeRequest(msg);

            if(devStatus!=updateStatus){
                qDebug() << deviceList->at(i)->name << " is now: " << updateStatus;
                updateStatus = !updateStatus;
            }
        }
    }
}
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在 Device 类构造函数中,我连接信号和槽:

Device::Device(){

    serialTimer.setSingleShot(true);
    QObject::connect(&serial, SIGNAL(readyRead()),
                     this, SLOT(handleResponse()));
    QObject::connect(&serialTimer, SIGNAL(timeout()),
                     this, SLOT(processTimeout()));
    QObject::connect(this, SIGNAL(writeRequest(QByteArray)),
                     this, SLOT(writeSerial(QByteArray)));
}
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currentStatus准备好要发送的消息后,emit writeRequest(msg);调用。这会调度一个连接到 slot 的信号writeRequest。writeRequest 用于设置消息并将其实际写入串行端口。

void Device::writeSerial(const QByteArray &msg){
    if (serial.portName() != "COM3") {
        serial.close();
        serial.setPortName("COM3");

        if (!serial.open(QIODevice::ReadWrite)) {
            processError(tr("Can't open %1, error code %2")
                         .arg(serial.portName()).arg(serial.error()));
            return;
        }

        if (!serial.setBaudRate(QSerialPort::Baud19200)) {
            processError(tr("Can't set rate 19200 baud to port %1, error code %2")
                         .arg(serial.portName()).arg(serial.error()));
            return;
        }

        if (!serial.setDataBits(QSerialPort::Data8)) {
            processError(tr("Can't set 8 data bits to port %1, error code %2")
                         .arg(serial.portName()).arg(serial.error()));
            return;
        }

        if (!serial.setParity(QSerialPort::NoParity)) {
            processError(tr("Can't set no patity to port %1, error code %2")
                         .arg(serial.portName()).arg(serial.error()));
            return;
        }

        if (!serial.setStopBits(QSerialPort::OneStop)) {
            processError(tr("Can't set 1 stop bit to port %1, error code %2")
                         .arg(serial.portName()).arg(serial.error()));
            return;
        }

        if (!serial.setFlowControl(QSerialPort::NoFlowControl)) {
            processError(tr("Can't set no flow control to port %1, error code %2")
                         .arg(serial.portName()).arg(serial.error()));
            return;
        }
    }
    qDebug() << "Message written";
    this->msgRequest = msg;
    serial.write(msgRequest);
    serialTimer.start(400);
}
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设置串行端口后,我将当前消息保存到msgRequest. 如果出现错误,可能必须使用它来重新发送消息。调用后serial.write(),我设置了一个 400ms 的计时器。一旦计时器到期,我就会检查从串行端口读取的内容。

handleResponse()是每次 QSerialPort 发出信号时调用的槽readyRead()readyRead()将任何可用数据附加到 QByteArray response

void Device::handleResponse(){
    response.append(serial.readAll());  
}
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400ms后,serialTimer(one shot Timer)会发出一个timeout()信号。serialTimer将我们请求的消息写入串行端口后立即启动。processTimeout()发送消息后,我们最终检查从 PowerLinc 调制解调器收到的响应。当消息发送到 INSTEON PowerLinc 调制解调器 (PLM) 时,PLM 会回显消息并附加 0x06(肯定 ACK)或 0x15(NACK)。在processTimeout()我检查以确保收到的最后一个字节是 ACK 字节,如果不是 - 重新发送我们最初请求的消息。

void Device::processTimeout(){
    qDebug() << "Read: " << response.toHex();
    int msgLength = this->msgRequest.length();
    if(response.at(msgLength)!=0x06){
        qDebug() << "Error, resend.";
        emit writeRequest(msgRequest);
    }
    response.clear();
}
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我使用串行端口监视器 4.0(Eltima Software)来验证串行端口上的写入和读取事务。下面,您可以看到 1 个示例事务的日志打印输出。

20:44:30:666 STATUS_SUCCESS 02 62 1d e9 4b 05 19 00   <--- Send
20:44:30:669 STATUS_SUCCESS 02 62 1d e9 4b 05 19 00 06   <--- Receive
20:44:30:875 STATUS_SUCCESS 02  <--- Receive
20:44:30:881 STATUS_SUCCESS 50 1d e9 4b 1e da f7 21 00 ff   <--- Receive
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对于 20 次发送,我收到了相同的回复。因此,我可以有把握地说,数据到达不一致的问题已经得到解决。现在我正在努力处理多个写入请求,但我相信这是一个需要调查的单独问题。我感谢大家的支持。