Diff: DebounceInt.h

Revision:

0:afa153f7249f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DebounceInt.h	Tue Feb 18 16:52:49 2014 +0000
@@ -0,0 +1,66 @@
+/* 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/
+
+//
+// Example Code: toggles LED1 on falling edge interrupt
+//#include "mbed.h"
+//#include "DebounceInt.h"
+//DigitalOut myled(LED1);
+//InterruptIn upPressed(p15);
+//DebounceInt *upPressedDebounce; //debounce object to be used within interrupt for joystick up
+//                                //note that pointer is defined here to have global variable
+//                                //but constructor call must be within the main function.
+//int main() {
+//  upPressedDebounce = new DebounceInt(p15,50000); //create DebounceInt object for p15 interrupt
+//                                                  //with a 50000 us delay (interrupt disabled to avoid bounce)                                    
+//  upPressed.fall(ISRup);            //attach joystick up click on falling edge, that is when
+//                                    //user releases the joystick the action will happen
+//  while(1){
+//  }
+//}
+//void ISRup(void){
+//    upPressedDebounce->debouncePinFall(); //call debounce method on pin fall, will disable interrupt for 
+//                                          //specified delay
+//    myled=!myled;
+//}
+
+
+#include "mbed.h"
+#include "InterruptMask.h"
+
+#ifndef DEBOUNCEINT
+#define DEBOUNCEINT
+#define _DEBOUNCEINTDELAYDEFAULT 50000 //useconds, this number would be about 50 ms
+#define _MINDBOUNCEDELAY 5
+class DebounceInt{
+public://members
+private://members
+    InterruptMask* pinIntMask; //Internal InterruptMask object
+    unsigned int delay; //this is the debounce delay, during which the interrupt in question is masked
+    Timeout debounceCallBack;
+
+public://methods
+    DebounceInt();     //Default constructor, required but not to be used, will yield error and exit.
+    DebounceInt(PinName pin);//Constructor with PinName, delay will remain default value
+    DebounceInt(PinName pin,unsigned int delay_us);//Constructor with PinName and specified delay in micro-seconds
+    void setDelay(unsigned int); //method to modify delay for debounce in us
+    void debouncePinRise(void);  //method to be called within Interrupt Service Routine to debounce GPIO pin on rising edge
+    void debouncePinFall(void);  //method to be called within Interrupt Service Routine to debounce GPIO pin on falling edge
+    
+private://methods
+    void debounceCallbackPinRise(void); //internal callback used to re-enable (unmask) interrupts on rising edge
+    void debounceCallbackPinFall(void); //internal callback used to re-enable (unmask) interrupts on falling edge
+    
+};
+
+#endif