jim hamblen / Mbed 2 deprecated Two_Pushbutton_Debounce_Interrupt

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Dependencies:   PinDetect mbed

Fork of Pushbutton_Debounce_Interrupt by jim hamblen

main.cpp@1:768b8bd42e33, 2013-01-29 (annotated)

Committer:
4180_1
Date:
Tue Jan 29 02:34:03 2013 +0000
Revision:
1:768b8bd42e33
Parent:
0:cc87c48aa43c 
ver 1.0

Who changed what in which revision?

UserRevisionLine numberNew contents of line
4180_1 0:cc87c48aa43c 1 #include "mbed.h"
4180_1 0:cc87c48aa43c 2 #include "PinDetect.h"
4180_1 0:cc87c48aa43c 3 // must import Cookbook PinDetct library into project
4180_1 0:cc87c48aa43c 4 // URL: http://mbed.org/users/AjK/libraries/PinDetect/lkyxpw
4180_1 0:cc87c48aa43c 5
4180_1 0:cc87c48aa43c 6 DigitalOut myled(LED1);
4180_1 0:cc87c48aa43c 7 DigitalOut myled2(LED2);
4180_1 0:cc87c48aa43c 8 DigitalOut myled3(LED3);
4180_1 0:cc87c48aa43c 9 DigitalOut myled4(LED4);
4180_1 0:cc87c48aa43c 10
4180_1 1:768b8bd42e33 11 PinDetect pb1(p8);
4180_1 1:768b8bd42e33 12 PinDetect pb2(p7);
4180_1 0:cc87c48aa43c 13 // SPST Pushbutton debounced count demo using interrupts and callback
4180_1 0:cc87c48aa43c 14 // no external PullUp resistor needed
4180_1 0:cc87c48aa43c 15 // Pushbutton from P8 to GND.
4180_1 1:768b8bd42e33 16 // Second Pushbutton from P7 to GND.
4180_1 0:cc87c48aa43c 17 // A pb hit generates an interrupt and activates the callback function
4180_1 0:cc87c48aa43c 18 // after the switch is debounced
4180_1 0:cc87c48aa43c 19
4180_1 0:cc87c48aa43c 20 // Global count variable
4180_1 0:cc87c48aa43c 21 int volatile count=0;
4180_1 0:cc87c48aa43c 22
4180_1 1:768b8bd42e33 23 // Callback routine is interrupt activated by a debounced pb1 hit
4180_1 1:768b8bd42e33 24 void pb1_hit_callback (void) {
4180_1 0:cc87c48aa43c 25 count++;
4180_1 0:cc87c48aa43c 26 myled4 = count & 0x01;
4180_1 0:cc87c48aa43c 27 myled3 = (count & 0x02)>>1;
4180_1 0:cc87c48aa43c 28 myled2 = (count & 0x04)>>2;
4180_1 0:cc87c48aa43c 29 }
4180_1 1:768b8bd42e33 30 // Callback routine is interrupt activated by a debounced pb2 hit
4180_1 1:768b8bd42e33 31 void pb2_hit_callback (void) {
4180_1 1:768b8bd42e33 32 count--;
4180_1 1:768b8bd42e33 33 myled4 = count & 0x01;
4180_1 1:768b8bd42e33 34 myled3 = (count & 0x02)>>1;
4180_1 1:768b8bd42e33 35 myled2 = (count & 0x04)>>2;
4180_1 1:768b8bd42e33 36 }
4180_1 0:cc87c48aa43c 37 int main() {
4180_1 0:cc87c48aa43c 38
4180_1 1:768b8bd42e33 39 // Use internal pullups for pushbutton
4180_1 1:768b8bd42e33 40 pb1.mode(PullUp);
4180_1 1:768b8bd42e33 41 pb2.mode(PullUp);
4180_1 0:cc87c48aa43c 42 // Delay for initial pullup to take effect
4180_1 0:cc87c48aa43c 43 wait(.01);
4180_1 1:768b8bd42e33 44 // Setup Interrupt callback functions for a pb hit
4180_1 1:768b8bd42e33 45 pb1.attach_deasserted(&pb1_hit_callback);
4180_1 1:768b8bd42e33 46 pb2.attach_deasserted(&pb2_hit_callback);
4180_1 1:768b8bd42e33 47 // Start sampling pb inputs using interrupts
4180_1 1:768b8bd42e33 48 pb1.setSampleFrequency();
4180_1 1:768b8bd42e33 49 pb2.setSampleFrequency();
4180_1 0:cc87c48aa43c 50 //Blink myled in main routine forever while responding to pb changes
4180_1 0:cc87c48aa43c 51 // via interrupts that activate the callback counter function
4180_1 0:cc87c48aa43c 52 while (1) {
4180_1 0:cc87c48aa43c 53 myled = !myled;
4180_1 0:cc87c48aa43c 54 wait(.5);
4180_1 0:cc87c48aa43c 55 }
4180_1 0:cc87c48aa43c 56
4180_1 0:cc87c48aa43c 57 }