DebouncedInterrupt.cpp

00001 /**
00002 * DebouncedInterrupt.cpp
00003 **/
00004 #include "DebouncedInterrupt.h"
00005 
00006 Timeout timeout;
00007 
00008 DebouncedInterrupt::DebouncedInterrupt(PinName pin)
00009 {
00010     _in = new InterruptIn(pin);
00011     _din = new DigitalIn(pin);
00012 }
00013 
00014 DebouncedInterrupt::~DebouncedInterrupt()
00015 {
00016     delete _in;
00017     delete _din;
00018 }
00019 
00020 void DebouncedInterrupt::attach(void (*fptr)(void), const gpio_irq_event trigger, const unsigned int& debounce_ms)
00021 {
00022     if(fptr) {
00023         _fAttach.attach(fptr);
00024         _last_bounce_count = _bounce_count = 0;
00025         _debounce_us = 1000*debounce_ms;
00026         _trigger = trigger;
00027         
00028         switch(trigger)
00029         {
00030             case IRQ_RISE:
00031                 _in->rise(this, &DebouncedInterrupt::_onInterrupt);
00032                 break;
00033             case IRQ_FALL:
00034                 _in->fall(this, &DebouncedInterrupt::_onInterrupt);
00035                 break;
00036             case IRQ_NONE:
00037                 reset(); // Unexpected. Clear callbacks.
00038                 break;
00039         }
00040     } else {
00041         reset();
00042     }
00043 }
00044 
00045 void DebouncedInterrupt::reset()
00046 {
00047     timeout.detach();
00048 }
00049 
00050 unsigned int DebouncedInterrupt::get_bounce()
00051 {
00052     return _last_bounce_count;
00053 }
00054 
00055 void DebouncedInterrupt::_callback()
00056 {
00057     _last_bounce_count = _bounce_count;
00058     _bounce_count = 0;
00059     if(_din->read() == (_trigger==IRQ_RISE)) {
00060         _fAttach.call();
00061     }
00062 }
00063 
00064 void DebouncedInterrupt::_onInterrupt()
00065 {
00066     _bounce_count++;
00067     timeout.attach_us(this, &DebouncedInterrupt::_callback, _debounce_us);
00068 }