controll led, button, GPIO with QT

hi guys, can u explain step by step how to make a program using QT to
control LED, buttons, and GPIO in mini2440? i really need your advice.
thanks

http://www.youtube.com/watch?v=ghzRuwEAWdo

thanks electutorial for your reply.
i have tried your tutorial in youtube and it's very help me.thanks a lot!
now i'm trying to make a program to control another peripherals on mini2440
with QT. i searched in google and it's so hard to find. do you have another
example?

I will make more video in the future I stop making them cause they are not
very popular.

may be your video wasn't popular, but it helped me and the others i
think.:)

oh ya, can i request a video how to controll led with button in board? or
may be how to control the con pin in mini 2440?

sure that would be the next video. :)

@shaco, have you gone through all the material available on andahammer.com
site for the mini2440 ? also many people have had success translating few
chapters of the Chinese user manual (using google's free online translation
service).

It's a shame, FriendlyARM doesn't translate the doc properly. Google
auto-translator is not bad, but some human touch, by someone who knows
Chinese and English well enough, would give it the golden touch.

@electutorial, nice video tute. look forward to more.

@electutorial, ok, tell me when you video finished.

@Icarus, thanks for your reply. i have gone there, and i don't find
tutorial to develop mini2440 with QT in linux. i'm new in embedded system,
especially using mini2440. so i need many references that can help me.
Icarus, what tool si you use to develop mini2440?

@shaco: Hope this link can help you: 
http://ultimatewebfree.kinssha.org/index.php/tutorielmini2440
(it uses French?

@electutorial: thanks for you videos. its really helpful for beginner like
me!. waiting next video.
best regards.

Hi all,
This is my GPIO class I've written in my captions project last year, you
can use it to control whatever GPIO pins you want:

file gpio.h
/****************************************************************************
**
** Copyright (C) 2010 FPT University FUEMES group.
** All rights reserved.
** Contact: FPT University http://www.fpt.edu.vn
**
** This file is part of the demonstration applications of the FUEMES
mini2440 client
**
** $FUEMES_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** FUEMES group at fuemes@gmail.com.
** $FUEMES_END_LICENSE$
**
****************************************************************************/
#ifndef GPIO_H
#define GPIO_H

#include <qstring.h>
#include <qobject.h>

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

//Header pin number definitions
#define PIN9    160
#define PIN10   161
#define PIN11   162
#define PIN12   163
#define PIN13   164
#define PIN14   165
#define PIN15   166
#define PIN16   192
#define PIN17   193
#define PIN18   195
#define PIN19   197
#define PIN20   198
#define PIN21   199
#define PIN22   201
#define PIN23   202
#define PIN24   203
#define PIN25   139
#define PIN26   140
#define PIN27   141
#define PIN28   194
#define PIN29   142
#define PIN30   143
#define PIN31   32
#define PIN32   33
#define PIN33   233
#define PIN34   234

class GPIO : public QObject
{
    Q_OBJECT
public:
    GPIO(int pin); //pin is the pin nuber on con4 of the FriendlyARM board
    ~GPIO();
 
    enum Direction {In,Out,Err};
    int openPin();
    int closePin();
    int setDirection(Direction direction); //set direction in/out. returns
0 if ok and -1 on error
    int getDirection(); //returns direction
    int setState(bool state);
    void setValue(bool value);
    bool getState();
public:
       
       
private:
        Direction  _direction;
        int _state;
        int _pinNumber;
        QString _directionString;
        QString _valueString;
        QString _strPin;
};
#endif // GPIO_H

file gpio.c

#include "mini2440Gpio.h"
//------------------------------------------------------------------------------
--------------------------
GPIO::GPIO(int pin)
{       _pinNumber = pin;
        _valueString = QString("/sys/class/gpio/gpio%1/value").arg(pin);
        _directionString =
QString("/sys/class/gpio/gpio%1/direction").arg(pin);
        _strPin = QString("%1").arg(pin);
}
//------------------------------------------------------------------------------
--------------------------
GPIO::~GPIO()
{
FILE * fp;
//This will create the folder /sys/class/gpio/gpio37
                if ((fp = fopen("/sys/class/gpio/unexport", "ab")) == NULL)
return;
                rewind(fp);             //Set pointer to begining of the
file
                fwrite(_strPin.toLatin1(), sizeof(char),_strPin.length() ,
fp);
                fclose(fp);
}
//------------------------------------------------------------------------------
--------------------------
int GPIO::openPin()
{
FILE * fp;
//This will create the folder /sys/class/gpio/gpio37
        if ((fp = fopen("/sys/class/gpio/export", "ab")) == NULL) return
-1;    
        rewind(fp);//Set pointer to begining of the file
        fwrite(_strPin.toLatin1(), sizeof(char),_strPin.length() , fp);
        fclose(fp);
        return 0;
}
//------------------------------------------------------------------------------
--------------------------
int GPIO::closePin()
{
FILE * fp;
//This will create the folder /sys/class/gpio/gpio37
                if ((fp = fopen("/sys/class/gpio/unexport", "ab")) == NULL)
return -1;          
                rewind(fp);//Set pointer to begining of the file
                fwrite(_strPin.toLatin1(), sizeof(char),_strPin.length() ,
fp);
                fclose(fp);
                return 0;
}
//------------------------------------------------------------------------------
--------------------------
int GPIO::setDirection(Direction direction)
{ //set direction in/out. returns 0 if ok and -1 on error
        FILE * fp;
        if ((fp = fopen(_directionString.toLatin1(), "rb+")) == NULL)
return -1;
        rewind(fp);//Set pointer to begining of the file
        if(direction == In)  fwrite("in", sizeof(char),2, fp);
        if(direction == Out) fwrite("out", sizeof(char),3, fp);
        fclose(fp);
        return 0;
}
//------------------------------------------------------------------------------
--------------------------
/*
int GPIO::getDirection()
{//returns direction
        
}*/
//------------------------------------------------------------------------------
--------------------------
int GPIO::setState(bool state)
{//state is 0 or 1. No effect if other value. returns the new state or -1
on error
    FILE * fp;
    if ((fp = fopen(_valueString .toLatin1(), "rb+")) == NULL) return -1;
    rewind(fp);//Set pointer to begining of the file
    if(state) fwrite("high", sizeof(char),4, fp);
    else fwrite("low", sizeof(char),3, fp);
    fclose(fp);
    return 0;
}

//------------------------------------------------------------------------------
--------------------------
bool GPIO::getState()
{       //returns 1 or 0 - the pin state. Returns -1 on error
FILE * fp;
char value;
        if ((fp = fopen(_valueString.toLatin1(), "rb+")) == NULL) return
false;
        rewind(fp);//Set pointer to begining of the file
        fread(&value, sizeof(char),1, fp);
        fclose(fp);
        if(value=='1') return true;
        if(value=='0') return false;
        return false;
}
//------------------------------------------------------------------------------
--------------------------


to use gpio class you just declare like this:
    GPIO test = new GPIO(PIN32);
    test->openPin(); // open pin
    test->setDirection(GPIO::Out); // set direction to output
    test->setState(false); // set value to low.
    test->closePin();//close pin
    delete test; // delete pointer to avoid leak memory.

Have funs!

@Coungle, thanks for your reply, ya its in  frances. now i'am trying to
develop an application  with qt for mini2440. i need some  resources how to
develop it. do u have any information?

@TungPham,thanks  for your reply, it will help everyone  here. where can i
found information about the function of the pin (Header pin number
definitions)?

Hi, there are some links I think that can help you:
http://www.youtube.com/watch?v=VmXN6JNndms
http://www.youtube.com/watch?v=ghzRuwEAWdo

Good luck.

@shaco: the GPIO informations you can see there:
http://www.avrfreaks.net/wiki/index.php/Documentation:Linux/GPIO

@TungPham, thanks for your reply. i have read it, but i still don't
understand what is the function of every pin that you wrote in the program?
if i want to use another pin, shoul i change the gpio.h?

//Header pin number definitions
#define PIN9    160
#define PIN10   161

Are codes for Mini6410-pins the same?
Where can I find it?

hi
i have problem on my mini2440 board there is no gpio directory i.e.
/sys/class thats it so how i can put gpio directory on board

Tick the correct kernel options and re-compile.

Which kernel are you using?

can you please tell me on which pin led are connected in mini2440|s3c2440
ARM9(friendly arm). and kindly tell me which pins are free here which can
be further connected to a relay.???

vipul garg,

you simply should take a look into the Mini2440's schematic.

thank you I was searching for this I already managed to use gpio's from
linux command console. But did not have any qt sources. I 

will try the code

Hello,
In Qt how to open a node /dev/adc for reading a data??
thanks

@TungPham 

Can you show how to use getState in QT program to detect pushbutton?