Andrew Reed / Mbed 2 deprecated Pushbutton_Debounce_Interrupt_V2

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Dependencies:   mbed PinDetect

main.cpp@2:535d154caa12, 2019-11-12 (annotated)

Committer:
reedas
Date:
Tue Nov 12 10:16:26 2019 +0000
Revision:
2:535d154caa12
Parent:
1:768b8bd42e33 
CITY1082 debounced button example

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);
reedas 2:535d154caa12 7 DigitalOut myled2(LED5);
reedas 2:535d154caa12 8 DigitalOut myled3(LED4);
reedas 2:535d154caa12 9 DigitalOut myled4(LED3);
4180_1 0:cc87c48aa43c 10
reedas 2:535d154caa12 11 PinDetect pb1(P0_4);
reedas 2:535d154caa12 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
reedas 2:535d154caa12 21 int volatile countit=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) {
reedas 2:535d154caa12 25 // printf("Count is %d\n", ++countit);
reedas 2:535d154caa12 26 countit--;
reedas 2:535d154caa12 27 myled4 = countit & 0x01;
reedas 2:535d154caa12 28 myled3 = (countit & 0x02)>>1;
reedas 2:535d154caa12 29 myled2 = (countit & 0x04)>>2;
4180_1 0:cc87c48aa43c 30 }
4180_1 1:768b8bd42e33 31 // Callback routine is interrupt activated by a debounced pb2 hit
reedas 2:535d154caa12 32 /*void pb2_hit_callback (void) {
4180_1 1:768b8bd42e33 33 count--;
4180_1 1:768b8bd42e33 34 myled4 = count & 0x01;
4180_1 1:768b8bd42e33 35 myled3 = (count & 0x02)>>1;
4180_1 1:768b8bd42e33 36 myled2 = (count & 0x04)>>2;
reedas 2:535d154caa12 37 }*/
4180_1 0:cc87c48aa43c 38 int main() {
4180_1 0:cc87c48aa43c 39
4180_1 1:768b8bd42e33 40 // Use internal pullups for pushbutton
4180_1 1:768b8bd42e33 41 pb1.mode(PullUp);
reedas 2:535d154caa12 42 // pb2.mode(PullUp);
4180_1 0:cc87c48aa43c 43 // Delay for initial pullup to take effect
4180_1 0:cc87c48aa43c 44 wait(.01);
4180_1 1:768b8bd42e33 45 // Setup Interrupt callback functions for a pb hit
4180_1 1:768b8bd42e33 46 pb1.attach_deasserted(&pb1_hit_callback);
reedas 2:535d154caa12 47 // pb2.attach_deasserted(&pb2_hit_callback);
4180_1 1:768b8bd42e33 48 // Start sampling pb inputs using interrupts
4180_1 1:768b8bd42e33 49 pb1.setSampleFrequency();
reedas 2:535d154caa12 50 // pb2.setSampleFrequency();
4180_1 0:cc87c48aa43c 51 //Blink myled in main routine forever while responding to pb changes
4180_1 0:cc87c48aa43c 52 // via interrupts that activate the callback counter function
4180_1 0:cc87c48aa43c 53 while (1) {
4180_1 0:cc87c48aa43c 54 myled = !myled;
4180_1 0:cc87c48aa43c 55 wait(.5);
4180_1 0:cc87c48aa43c 56 }
4180_1 0:cc87c48aa43c 57
4180_1 0:cc87c48aa43c 58 }