WizziLab / DebouncedInterrupt

A replacement for InterruptIn that debounces the interrupt.

Dependents:   D7A_Demo-Get-started CVtoOSCConverter EE3501keypad D7A_Localisation ... more

Fork of DebouncedInterrupt by Anil Kandangath

Example code:

#include "DebouncedInterrupt.h"

DebouncedInterrupt up_button(USER_BUTTON);

void onUp()
{
    // Do Something
}

int main()
{
    // Will immediatly call function and ignore other interrupts until timeout
    up_button.attach(&onUp, IRQ_FALL, 1000, true);

    // Will call function only if button has been held for the specified time
    //up_button.attach(&onUp, IRQ_FALL, 500, false);

    while(1) {}
}

DebouncedInterrupt.cpp

Committer:
kandangath
Date:
2014-02-25
Revision:
21:34b95e1b2bf3
Parent:
19:d12a5b89ac3a
Child:
22:9733f886810a

File content as of revision 21:34b95e1b2bf3:

/**
* DebouncedInterrupt.cpp
**/
#include "DebouncedInterrupt.h"

Timeout timeout;

DebouncedInterrupt::DebouncedInterrupt(PinName pin)
{
    _in = new InterruptIn(pin);
    _din = new DigitalIn(pin);
}

DebouncedInterrupt::~DebouncedInterrupt()
{
    delete _in;
    delete _din;
}

void DebouncedInterrupt::attach(void (*fptr)(void), const gpio_irq_event trigger, const unsigned int& debounce_ms)
{
    attach(this, fptr, trigger, debounce_ms);
}

template<typename T>
void DebouncedInterrupt::attach(T *cptr, void (*fptr)(void), const gpio_irq_event trigger, const unsigned int& debounce_ms)
{
    if(fptr) {
        fCallback = fptr;
        _last_bounce_count = _bounce_count = 0;
        _debounce_us = 1000*debounce_ms;
        _trigger = trigger;
        
        switch(trigger)
        {
            case IRQ_RISE:
                _in->rise(cptr, &DebouncedInterrupt::_onInterrupt);
                break;
            case IRQ_FALL:
                _in->fall(cptr, &DebouncedInterrupt::_onInterrupt);
                break;
            case IRQ_NONE:
                reset(); // Unexpected. Clear callbacks.
                break;
        }
    } else {
        reset();
    }
}

void DebouncedInterrupt::reset()
{
    timeout.detach();
}

unsigned int DebouncedInterrupt::get_bounce()
{
    return _last_bounce_count;
}

void DebouncedInterrupt::_callback()
{
    _last_bounce_count = _bounce_count;
    _bounce_count = 0;
    if(_din->read() == (_trigger==IRQ_RISE)) {
        fCallback();
    }
}

void DebouncedInterrupt::_onInterrupt()
{
    _bounce_count++;
    timeout.attach_us(this, &DebouncedInterrupt::_callback, _debounce_us);
}