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QextSerialPort port->write Problem

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mannion

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  • "mannion" started this thread

Posts: 18

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1

Tuesday, May 3rd 2011, 2:55pm

QextSerialPort port->write Problem

I seem to be having difficulty using the
PortListener class. If I write to a connected port directly everything is fine.
If I write via a public or private function using identical code I get an error:


“Application.exe has encountered a problem
and needs to close.”


It seems a bizarre problem so I must be
missing something really simple. My apologies in advance if this is the case. I
have cut the code down to a minimal case that still generates the problem.

Source code

 
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MainWindow::MainWindow(QWidget *parent):
QMainWindow(parent){

    QWidget *w = new QWidget(this);

    scPtr
= new Session ();

    QString portName
= scPtr->enumerate();

    if (portName
== "NULL"){

        qDebug()
<< "Serial Device NOT FOUND portName = " <<
portName;

        int i = QMessageBox::warning(this,tr("Connection"),tr("No
SerialDevices detected."),QMessageBox::Cancel);

    }else{
qDebug() << "SerialDevice Found. portName = " <<
portName; }

    PortListener
*listener = new PortListener(portName); 

     

//============ below
does not work?===============

    clickTEST0();

     

//============ below
works======================

    QByteArray ba;

    ba.resize(3);

    ba[0]
= 254
;              


    ba[1]
= 1;   	

    ba[2]
= 255;

    int i =
listener->port->write(ba,ba.length());

}

 

void MainWindow::clickTEST0()
{

    QByteArray ba;

    ba.resize(3);

    ba[0]
= 254
;              


    ba[1]
= 1; 

    ba[2]
= 255;

    int i =
listener->port->write(ba,ba.length());

}

 

Session::Session(){}


 

QString Session::enumerate(){

    QList<QextPortInfo>
ports = QextSerialEnumerator::getPorts();

    int tempport
= 9999;

    QString tempportname
= "NULL";

    QString tempfriendname
= "NULL";

    QString qstr;              


    int portsize
= 0;

    for (int i = 0;
i < ports.size(); i++) {

        portsize++;

        qstr
= ports.at(i).enumName;

        if (qstr
==  SerialDeviceString) {

            tempport
= i;

            tempportname
= ports.at(i).portName;

            tempfriendname
= ports.at(i).friendName;

        }
else {}

    }

    QString portName
= tempportname;        // update this
to use your port of choice

    if (portName
== "NULL"){ qDebug() << "SerialDevice NOT FOUND portName =
" << portName;

    }else{
qDebug() << " SerialDevice FOUND portName = " <<
portName; }

    return portName;

}

 

PortListener::PortListener(const QString &
portName) {  //, int iVal){ 	//portName =
this->enumerate();

    if (portName=="NULL"){
//NOT CONNECTED

    }else{
SetPort(portName);  }

}

 

void PortListener::SetPort(const QString &
portName){   

    this->port
= new QextSerialPort(portName, QextSerialPort::EventDriven);

    port->setBaudRate(BAUD115200);

    port->setFlowControl(FLOW_OFF);

    port->setParity(PAR_NONE);

    port->setDataBits(DATA_8);

    port->setStopBits(STOP_1);         


    if (port->open(QIODevice::ReadWrite)
== true) {

        connect(port,
SIGNAL(readyRead()), this, SLOT(onReadyRead()));

        connect(port,
SIGNAL(dsrChanged(bool)), this, SLOT(onDsrChanged(bool)));

        if (!(port->lineStatus()
& LS_DSR))

            qDebug()
<< "warning: device is not turned on";

        qDebug()
<< "listening for data on"
<< port->portName();

    }

    else {qDebug()
<< "device failed to open:"
<< port->errorString();
}

    emit
onReadyWrite("Listener Created!");

}

Similar threads

Used tags

PortListener, QextSerialPort, Serial, write