How can I see and storage the data from device in QT?

[dheerendra]

This requires good programming practise.

1. Whenever you click on the button, you need to open the device selected. Right now u have hard coded with mSerialport->setPortName("/dev/ttyUSB0");
2. use readyRead() signal to check the arrival of data.
3. use readAll() method to read all the data from device.
4. Display the data in QTextEdit UI control

[segtteee]

@dheerendra
Thank you for your reply. Does that mean you have to make a full correction my code? otherwise just change
" mSerialport->setPortName("/dev/ttyUSB0");" ??

[dheerendra]

only mSerialport->setPortName("/dev/ttyUSB0") this may be sufficient.

[segtteee]

@dheerendra
Can not I solve the problem without changing the "mSerialport->setPortName("/dev/ttyUSB0")" ? I do not think I can change it.

[jsulm]

@segtteee Why can't you change it?

[segtteee]

@jsulm
I can write code by specifying one port, but I can not write one after choosing multiple ports...i am a beginner sorry..

[jsulm]

@segtteee Then you should learn how to do it.
Where does the user select the port? Is it a QComboBox? Something else?

[segtteee]

@jsulm
it is combobox

[jsulm]

@segtteee Then just go to the documentation: http://doc.qt.io/qt-5/qcombobox.html#currentText-prop
Change

mSerialport->setPortName("/dev/ttyUSB0");

to

mSerialport->setPortName(ui->comboBox->currentText()); // Change the name of the combobox if it's called differently in your code

Really easy, isn't it? :-)

[segtteee]

@jsulm
I modified the port name as you told me. I also changed baudrate and databite equally, but here I get an error.
"" no matching function for call to ‘QSerialPort::setBaudRate(QString)’
mSerialport->setBaudRate(ui->comboBox_baudrate->currentText()); ""
Can I change only the port name?

[Kicer86]

@segtteee said in How can I see and storage the data from device in QT?:

Can I change only the port name?

If you want to hardcode all values in code, why do you put comboboxes in ui?

[jsulm]

@segtteee See the documentation: http://doc.qt.io/qt-5/qserialport.html#baudRate-prop
setBaudRate() takes an integer not a string.
See again documentation to find out how to convert a string to an integer: http://doc.qt.io/qt-5/qstring.html#toInt

mSerialport->setBaudRate(ui->comboBox_baudrate->currentText().toInt());

[segtteee]

@jsulm
I understand that the port name is a string, and baudrate is a number, so toint is an integer, but databits is a number, why not toint? And paritybits is a character, but it should not be used.

[jsulm]

@segtteee said in How can I see and storage the data from device in QT?:

databits is a number, why not toint?

I don't understand. If it is a number then convert it to a number like baud rate.

"And paritybits is a character, but it should not be used" - don't know what you mean. If it should not be used then don't use it.

[segtteee]

@jsulm
it mean
port name = string so currentText()
baud rate = integer so currentText().toint()

data bits = integer so ??
Is not the toint() correct for the data bits? but error occured

[jsulm]

@segtteee Could you please show real code and the error message?
DataBits is an enum, so you can do something like:

DataBits dataBits;
if (ui->dataBits.currentText() == "Data5")
    dataBits = DataBits::Data5;
else if ...

[segtteee]

@jsulm

[jsulm]

@segtteee See my previous post

[segtteee]

@jsulm

if (ui->comboBox_databits->currentText() == "Data8")
mSerialport->setDataBits("Data8") ;
error occured ..

[jsulm]

@segtteee First, please read what I write more carefully, second if you get an error please post it.
This is wrong:

if (ui->comboBox_databits->currentText() == "Data8")
    mSerialport->setDataBits("Data8") ;

As I wrote above setDataBits takes an enum not a string - why do you try to pass a string?
You should really read documentation.
Here again the code I already posted before:

DataBits dataBits;
if (ui->dataBits.currentText() == "Data5")
    dataBits = DataBits::Data5;
else if ..
...
// new
mSerialport->setDataBits(dataBits) ;