Serial data interrupt when minimizing a display window.

[nagabathula]

Hello every one,
i have a small problem. I am acquiring data from a serial port every 200 milli seconds and saving it into a database. I show this saved data in another display window. Every thing runs fine but when i minimize or double click on the top QDialogBox bar to minimize or maximize the dialogbox i get a interrupt in the data acquiring i miss acquiring some data from the serial port when i try to minimize or maximize the QDialogBox. I am retrieving the data in the main program and i display it in another QDialogBox i get some missing data when i minimize or maximize this QDialogBox in which i display the data in QTableView format. I checked the incoming data from the serial port with QDebug i see some data missing when i do the minimize or maximize operation on the window. What could be the problem..?? Pls help me out. !!

Thank you

[nagabathula]

hello friends is there any way serial data acquiring can get interrupted when i minimize or maximize a dialog window.. I am sure it is happening only when i try to min or max a dialog window. I see in qDebug some missing data when i do the min max operations.
this is what i have put to maximize and minimize the windows. ..

: QMainWindow(parent,Qt::WindowMinMaxButtonsHint)
: QDialog(parent,Qt::WindowMinMaxButtonsHint)

some one pls help me, what might the problem be.
thank you

[squidge]

What is your serial buffer size?

How are you collecting the data?

[nagabathula]

Hello thank you for the reply.
The serial buffer size is char buff[16384]; i am acquiring data when i click the acquire button i call this function every 200 mili sec's. I save the data in the QByteArray to a data base and then display it in another QDialogbox. The acquiring of the serial data happens in QMainWindow.cpp . The data acquiring is continuous only when i double click or try to minimize the QDialogbox in which i display the data from the db, there is some data missing. I checked that with qDebug().

if(port->bytesAvailable())
	{
		numBytes = port->bytesAvailable();
		if(numBytes > sizeof(buff))
			numBytes = sizeof(buff);
		ist = port->read(buff,numBytes);
		newdata.append(QByteArray::fromRawData(buff,numBytes));
                qDebug()<<newdata;
              // And some processing before i save the data in the db
       }

if(port->bytesAvailable())
	{
		numBytes = port->bytesAvailable();
		if(numBytes > sizeof(buff))
			numBytes = sizeof(buff);
		ist = port->read(buff,numBytes);
		newdata.append(QByteArray::fromRawData(buff,numBytes));
                qDebug()<<newdata;
              // And some processing before i save the data in the db
       }

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thank you

[squidge]

char buff[16384]; is your buffer, not the buffer of the serial port. What is the buffer of the serial port?

[schnitzel]

You are using QextSerialPort - right?
Have you considered using eventdriven mode because it looks like you are more or less polling. Using events could work a lot better for you.
Take a look at QextSeriaPort event example.

[nagabathula]

Hello thank you for the time.

i din understand what you meant by serial port buffer.? and eventdriven mode does not work on my system it tells

'EventDriven' : is not a member of 'QextSerialPort'

This is what i am doing right now to set the portsettings

port = new QextSerialPort(port_name);
	port->setBaudRate(BAUD115200);	     //(BAUD115200);
	port->setFlowControl(FLOW_OFF);		 //  (FLOW_OFF);
	port->setParity(PAR_NONE);			 //(PAR_NONE); 
	port->setDataBits(DATA_8);			 //(DATA_8);   
        port->setStopBits(STOP_1);

port = new QextSerialPort(port_name);
	port->setBaudRate(BAUD115200);	     //(BAUD115200);
	port->setFlowControl(FLOW_OFF);		 //  (FLOW_OFF);
	port->setParity(PAR_NONE);			 //(PAR_NONE); 
	port->setDataBits(DATA_8);			 //(DATA_8);   
        port->setStopBits(STOP_1);

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i changed it to this but it gives a error that eventDriven is not a member of QextSerialPort i have a 2 year old version of qextserialport i think i need to update the patch.

port = new QextSerialPort( port_name, QextSerialPort::EventDriven);
if (port->open(QIODevice::ReadWrite | QIODevice::Unbuffered) == true)
{
        port = new QextSerialPort(port_name);
	port->setBaudRate(BAUD115200);	     //(BAUD115200);
	port->setFlowControl(FLOW_OFF);		 //  (FLOW_OFF);
	port->setParity(PAR_NONE);			 //(PAR_NONE); 
	port->setDataBits(DATA_8);			 //(DATA_8);   
        port->setStopBits(STOP_1); 
}

port = new QextSerialPort( port_name, QextSerialPort::EventDriven);
if (port->open(QIODevice::ReadWrite | QIODevice::Unbuffered) == true)
{
        port = new QextSerialPort(port_name);
	port->setBaudRate(BAUD115200);	     //(BAUD115200);
	port->setFlowControl(FLOW_OFF);		 //  (FLOW_OFF);
	port->setParity(PAR_NONE);			 //(PAR_NONE); 
	port->setDataBits(DATA_8);			 //(DATA_8);   
        port->setStopBits(STOP_1); 
}

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thank you.

[squidge]

Why are you passing Unbuffered to QextSerialPort?

[schnitzel]

Hello thank you for the time.



i changed it to this but it gives a error that eventDriven is not a member of QextSerialPort i have a 2 year old version of qextserialport i think i need to update the patch.

not much point in fighting obsolete code... please update to the latest and take a look at the event driven example.

good luck