Diff: DebounceInt.cpp

Revision:

0:afa153f7249f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DebounceInt.cpp	Tue Feb 18 16:52:49 2014 +0000
@@ -0,0 +1,73 @@
+/* DebounceInt Library */
+/* This class enables debouncing a GPIO interrupt from a specific MBED pin            */
+/* It does so by using the InterruptMask library to temporarily mask the interrupt    */
+/* from the specified pin for a user specified delay specified in us. After the delay */
+/* time has passed the interrupt is unmasked (reenabled) and any pending interrupts   */
+/* also cleared. The library gives you the flexibiity to debounce on either the       */
+/* rising or falling edge interrupts.                                                 */
+// Usage:
+// Declare a DebounceInt object with a valid mbed pin (p5-p30 except p19 and p20) as 
+// an argument. Within your interrupt service routine call the appropriate debounce
+// method debouncePinRise or debouncePinFall. 
+// Requires the InterruptMask library available at: https://mbed.org/users/nleoni/code/InterruptMask/
+
+#include "DebounceInt.h"
+
+//Default constructor, required but not to be used, will yield error and exit.
+    DebounceInt::DebounceInt(){
+        exit(1);
+    }
+    
+//Constructor with PinName, delay will remain default value
+    DebounceInt::DebounceInt(PinName pin){
+    // Inputs:
+    // PinName pin: Expected Proper Mbed Pin (e.g. p12), program will exit otherwise
+        this->pinIntMask = new InterruptMask(pin);
+        this->setDelay(_DEBOUNCEINTDELAYDEFAULT);    
+    }
+
+//Constructor with PinName and specified delay in micro-seconds
+    DebounceInt::DebounceInt(PinName pin,unsigned int delay_us){
+    // Inputs:
+    // PinName pin: Expected Proper Mbed Pin (e.g. p12), program will exit otherwise
+    // unsigned int delay: Expected positive delay, will force delay to be larger
+    // than minimum delay _MINDBOUNCEDELAY
+        this->pinIntMask = new InterruptMask(pin);        
+        this->setDelay(delay_us);
+    }
+
+//method to modify delay for debounce in us
+    void DebounceInt::setDelay(unsigned int delay_us){
+    // Inputs:
+    // unsigned int delay: Expected positive delay, will force delay to be larger
+    // than minimum delay _MINDBOUNCEDELAY
+        if(delay_us>(_MINDBOUNCEDELAY) ){
+            this->delay=delay_us;
+        } else { 
+            this->delay=_MINDBOUNCEDELAY;
+        }
+    } 
+
+//method to be called within Interrupt Service Routine to debounce GPIO pin on rising edge
+    void DebounceInt::debouncePinRise(void){
+        this->pinIntMask->maskIntR();
+        this->debounceCallBack.attach_us(this,&DebounceInt::debounceCallbackPinRise,this->delay);
+    }
+    
+//internal callback used to re-enable (unmask) interrupts on rising edge
+    void DebounceInt::debounceCallbackPinRise(void){
+        this->pinIntMask->ClrInt();
+        this->pinIntMask->unMaskIntR();
+    }
+
+//method to be called within Interrupt Service Routine to debounce GPIO pin on falling edge
+    void DebounceInt::debouncePinFall(void){
+        this->pinIntMask->maskIntF();
+        this->debounceCallBack.attach_us(this,&DebounceInt::debounceCallbackPinFall,this->delay);
+    }
+    
+//internal callback used to re-enable (unmask) interrupts on falling edge
+    void DebounceInt::debounceCallbackPinFall(void){
+        this->pinIntMask->ClrInt();
+        this->pinIntMask->unMaskIntF();
+    }
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