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

segtteee

this is my ui
alt text
what i want

I am in serial communication qt with my device. I make a ui and I can connect my device using ui. I want get a data log from device and display in qt using QTimer.

how can I do it ? and also want save data to csv file.

please help me and let me know how can I solve the problem

below is my code.

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QtSerialPort/QSerialPort>
#include <QSerialPortInfo>
#include <QMessageBox>
#include <QObject>
#include <QIODevice>
#include <QDebug>
#include <QPlainTextEdit>
#include <QDateTime>

QSerialPort serial;
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow),
    mSerialport{new QSerialPort}
{
    ui->setupUi(this);

    connect(this->mSerialport,SIGNAL(readyRead()),
            this,SLOT(readSerialData()));
    connect(ui->pushButton_send,
            &QPushButton::clicked, [=](){
    sendMsg(ui->command->toPlainText());

    });

}
MainWindow::~MainWindow()
{
    delete mSerialport;
    delete ui;
}

void MainWindow::on_pushButton_connect_clicked()
{
    mSerialport->setPortName("/dev/ttyUSB0");
    mSerialport->setBaudRate(QSerialPort::Baud9600);
    mSerialport->setDataBits(QSerialPort::Data8);
    mSerialport->setParity(QSerialPort::NoParity);
    mSerialport->setStopBits(QSerialPort::OneStop);
    mSerialport->setFlowControl(QSerialPort::NoFlowControl);
    if (mSerialport->open(QIODevice::ReadWrite))
        { QMessageBox::information(this,tr("connect"),
                "serialcommunication start");
            }
        else {
            QMessageBox::information(this,tr("fail"),
               mSerialport->errorString());
            }

}

void MainWindow::on_pushButton_disconnect_clicked()
{
        QMessageBox::information(this, tr("disconnect"),
                    "serial communication end");
    mSerialport->close();
}

void MainWindow::sendMsg(const QString &msg)
{
      QString str = msg;
      str.append("\n");
      this->mSerialport->write(str.toLatin1());
      ui->comLog->insertPlainText(QDateTime::currentDateTime().
      toString("yyyy-MM-dd hh:mm:ss") + " [send] " + msg + "\n");
}

void MainWindow::recvMsg(){
      QByteArray msg = this->mSerialport->readAll();
      ui->comLog->insertPlainText(QDateTime::currentDateTime().
      toString("yyyy-MM-dd hh:mm:ss") + " [recieve] " + msg.toHex().
      data() + "\n");
}

dheerendra

This requires good programming practise.

Whenever you click on the button, you need to open the device selected. Right now u have hard coded with mSerialport->setPortName("/dev/ttyUSB0");
use readyRead() signal to check the arrival of data.
use readAll() method to read all the data from device.
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
alt text

jsulm

@segtteee See my previous post

segtteee

@jsulm

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