QtGui Serial Port & Arduino Serial Flow [SOLVED]

kuzulis

Use QtSerialPort, read documentation, see examples.

cherault

Thanks Kuzulis for your reply.

I read the docs and examples, but it doesn't work for my case...
Anyway, I will try one more time to do the job.

Thanks again.

Regards,

SGaist

Hi and welcome to devnet,

Why doesn't it work for you case ?

Can you describe your setup ?

cherault

Hi SGait,

Thanks for your reply.

I don't really have problems, because today I am just learning Qt5.
It's a fantastic tool, but I am just a little bit disapointed when I saw all we need to do to just to print on a widget a serial flow...
It's amazing !

Well, I follow my search to see how to set my *.pro and the QSerial lib.

The main goal for me is pretty simple:

Sending some flow on the serial port /dev/tty (Linux) and show them through the widget LCD of Qt, and that's it :-)

Cheers,

SGaist

/dev/tty is generally not a serial port but the default console.

Then you didn't try to write it 100% natively ;)

I must say that it doesn't require that much:
QSerialPort + QLCDNumber and a slot for processing the data coming from your Arduino

cherault

Hi,

Thank you a lot, I will try it.

Have a nice day.

Cheers,

cherault

Hi,

Ok, I did some test, and this my files:

.pro

@
QT += core gui serialport

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = Pitot
TEMPLATE = app

SOURCES += main.cpp
mainwindow.cpp

HEADERS += mainwindow.h

FORMS += mainwindow.ui
@

This is the header file:
@#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
Q_OBJECT

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();

private slots:

void on_lcdNumber_overflow();

private:
Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H
@

And the mainwindows.cpp:
@
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QSerialPort>
#include <QDebug>

QSerialPort serial;

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
serial= new QSerialPort(this);
serial->setPortName("/dev/ttyACM0");
serial->setBaudRate(QSerialPort::Baud9600);
serial->setDataBits(QSerialPort::Data8);
serial->setParity(QSerialPort::NoParity);
serial->setStopBits(QSerialPort::OneStop);
serial->setFlowControl(QSerialPort::NoFlowControl);
serial->open(QIODevice::ReadOnly);
connect(serial, SIGNAL(readyRead()),this,SLOT(serialReceived()));

}

MainWindow::~MainWindow()
{
delete ui;
serial->close();
}

void MainWindow::on_lcdNumber_overflow()
{
QByteArray qb;
qb=serial->readAll();
ui->lcdNumber->setDecMode(qb);
qDebug() << qb;
}
@

and the compilator says:

!file:///home/tux/Capture du 2014-12-26 10:18:28.png()!

cherault

Could you help me to solve this problem ?

Thanks in advance for your time and support.

Regards,

cherault

Ok, don't take in account my last post.
I solve a problem due to a pointer.

So, the only problem I have is the next, and this is the mainwindows.cpp:

@#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QSerialPort>
#include <QDebug>

QSerialPort *serial;

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
serial=new QSerialPort(this);
serial->setPortName("/dev/ttyACM0");
serial->setBaudRate(QSerialPort::Baud9600);
serial->setDataBits(QSerialPort::Data8);
serial->setParity(QSerialPort::NoParity);
serial->setStopBits(QSerialPort::OneStop);
serial->setFlowControl(QSerialPort::NoFlowControl);
serial->open(QIODevice::ReadOnly);
connect(serial, SIGNAL(readyRead()),this,SLOT(serialReceived()));

}

MainWindow::~MainWindow()
{
delete ui;
serial->close();
}

void MainWindow::on_lcdNumber_overflow()
{
QByteArray qb;
qb=serial->readAll();
ui->lcdNumber->setDecMode(qb);
qDebug() << qb;
}
@

So everything is fine but a line 35, I have a compilator problem.
It says:

/mainwindow.cpp:35: erreur : no matching function for call to 'QLCDNumber::setDecMode(QByteArray&)'
ui->lcdNumber->setDecMode(qb);
^
Could you tell me why it doesn't compile ?
I really don't understand.

Thanks for your help.

Regards,

cherault

Hi all,

Finally, I finished the job ! ;-)
The reason why I had some problems was the ByteArray, but now it works fine.
The modifications I did was:

void MainWindow::serialReceived()
{
QByteArray valeur;
valeur = serial->readAll();
float nb = valeur.toFloat();
ui->lcdNumber->display(nb);
}

And everythings lokk fine :-)

So thanks for your support.

Regards,

SGaist

Nice !

Since you have it working now, please update the thread title prepending [solved] so other forum users may know a solution has been found :)

Happy coding !