Revision 18:e6e9bc6402b7, committed 2014-02-19

Comitter:

kandangath

Date:

Wed Feb 19 01:47:45 2014 +0000

Parent:

17:96a51b236ba0

Child:

19:d12a5b89ac3a

Commit message:

Support checking rise and fall of signals

Changed in this revision

--- a/DebouncedInterrupt.cpp	Tue Feb 18 20:38:50 2014 +0000
+++ b/DebouncedInterrupt.cpp	Wed Feb 19 01:47:45 2014 +0000
@@ -17,15 +17,28 @@
     delete _din;
 }
 
-void DebouncedInterrupt::attach(void (*fptr)(void), const unsigned int& debounce_ms)
+void DebouncedInterrupt::attach(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;
         
-        _in->rise(this, &DebouncedInterrupt::_onInterrupt);
-        _in->fall(this, &DebouncedInterrupt::_onInterrupt);
+        switch(trigger)
+        {
+            case IRQ_RISE:
+                _in->rise(this, &DebouncedInterrupt::_onInterrupt);
+                break;
+            case IRQ_FALL:
+                _in->fall(this, &DebouncedInterrupt::_onInterrupt);
+                break;
+            case IRQ_NONE:
+                reset(); // Unexpected. Clear callbacks.
+                break;
+        }
+    } else {
+        reset();
     }
 }
 
@@ -43,7 +56,8 @@
 {
     _last_bounce_count = _bounce_count;
     _bounce_count = 0;
-    if(_din->read()) {
+    unsigned int expected_state = (_trigger==IRQ_RISE)?1:0;
+    if(_din->read() == expected_state) {
         fCallback();
     }
 }

--- a/DebouncedInterrupt.h	Tue Feb 18 20:38:50 2014 +0000
+++ b/DebouncedInterrupt.h	Wed Feb 19 01:47:45 2014 +0000
@@ -15,7 +15,7 @@
  * 
  * int main()
  * {
- *     up_button.attach(&onUp, 100);
+ *     up_button.attach(&onUp,IRQ_FALL, 100);
  *     while(1) {
  *         ...
  *     }
@@ -29,11 +29,20 @@
 #include <stdint.h>
 #include "mbed.h"
 
+/**
+typedef enum {
+    IRQ_NONE,
+    IRQ_RISE,
+    IRQ_FALL
+} gpio_irq_event;
+**/
+
 class DebouncedInterrupt {
 private:
     unsigned int _debounce_us;
     InterruptIn *_in;
     DigitalIn *_din;
+    gpio_irq_event _trigger;
     
     // Diagnostics
     volatile unsigned int _bounce_count;
@@ -47,7 +56,7 @@
     ~DebouncedInterrupt();
     
     // Start monitoring the interupt and attach a callback
-    void attach(void (*fptr)(void), const uint32_t& debounce_ms=10);
+    void attach(void (*fptr)(void), const gpio_irq_event trigger, const uint32_t& debounce_ms=10);
    
     // Stop monitoring the interrupt
     void reset();