main.cpp

00001 #include "mbed.h"
00002 #include "PinDetect.h"
00003 // must import Cookbook PinDetct library into project
00004 // URL: http://mbed.org/users/AjK/libraries/PinDetect/lkyxpw
00005 
00006 DigitalOut myled(LED1);
00007 DigitalOut myled2(LED5);
00008 DigitalOut myled3(LED4);
00009 DigitalOut myled4(LED3);
00010 
00011 PinDetect pb1(P0_4);
00012 //PinDetect pb2(p7);
00013 // SPST Pushbutton debounced count demo using interrupts and callback
00014 // no external PullUp resistor needed
00015 // Pushbutton from P8 to GND.
00016 // Second Pushbutton from P7 to GND.
00017 // A pb hit generates an interrupt and activates the callback function
00018 // after the switch is debounced
00019 
00020 // Global count variable
00021 int volatile countit=0;
00022 
00023 // Callback routine is interrupt activated by a debounced pb1 hit
00024 void pb1_hit_callback (void) {
00025 //   printf("Count is %d\n", ++countit);
00026     countit--;
00027     myled4 = countit & 0x01;
00028     myled3 = (countit & 0x02)>>1;
00029     myled2 = (countit & 0x04)>>2;
00030 }
00031 // Callback routine is interrupt activated by a debounced pb2 hit
00032 /*void pb2_hit_callback (void) {
00033     count--;
00034     myled4 = count & 0x01;
00035     myled3 = (count & 0x02)>>1;
00036     myled2 = (count & 0x04)>>2;
00037 }*/
00038 int main() {
00039 
00040     // Use internal pullups for pushbutton
00041     pb1.mode(PullUp);    
00042 //    pb2.mode(PullUp);
00043     // Delay for initial pullup to take effect
00044     wait(.01);
00045     // Setup Interrupt callback functions for a pb hit
00046     pb1.attach_deasserted(&pb1_hit_callback);
00047 //    pb2.attach_deasserted(&pb2_hit_callback);
00048     // Start sampling pb inputs using interrupts
00049     pb1.setSampleFrequency();
00050 //    pb2.setSampleFrequency();
00051     //Blink myled in main routine forever while responding to pb changes
00052     // via interrupts that activate the callback counter function
00053     while (1) {
00054         myled = !myled;
00055         wait(.5);
00056     }
00057 
00058 }