Nicholas Outram / Mbed OS Task522Solution

Task 5.2.2 Solution

main.cpp@1:69d2dd81cd48, 2017-07-13 (annotated)

Committer:
noutram
Date:
Thu Jul 13 14:55:53 2017 +0000
Revision:
1:69d2dd81cd48
Parent:
0:4e6cbb427cd7 
updated for mbed-os 5.5

Who changed what in which revision?

UserRevisionLine numberNew contents of line
noutram 0:4e6cbb427cd7 1 #include "mbed.h"
noutram 0:4e6cbb427cd7 2
noutram 0:4e6cbb427cd7 3 //Global objects
noutram 0:4e6cbb427cd7 4 DigitalOut onboardLed(LED1);
noutram 0:4e6cbb427cd7 5 DigitalOut redLED(D7);
noutram 0:4e6cbb427cd7 6 DigitalOut yellowLED(D6);
noutram 0:4e6cbb427cd7 7 DigitalOut greenLED(D5);
noutram 0:4e6cbb427cd7 8
noutram 0:4e6cbb427cd7 9 //Function prototypes (ISR)
noutram 0:4e6cbb427cd7 10 void doRedPWM();
noutram 0:4e6cbb427cd7 11 void doYellowPWM();
noutram 0:4e6cbb427cd7 12 void doGreenPWM();
noutram 0:4e6cbb427cd7 13
noutram 0:4e6cbb427cd7 14 //One-shot timers
noutram 0:4e6cbb427cd7 15 Timeout tRed;
noutram 0:4e6cbb427cd7 16 Timeout tYellow;
noutram 0:4e6cbb427cd7 17 Timeout tGreen;
noutram 0:4e6cbb427cd7 18
noutram 0:4e6cbb427cd7 19 //Interrupt Service Routine Flags
noutram 0:4e6cbb427cd7 20 volatile int redISRFlag = 0;
noutram 0:4e6cbb427cd7 21 volatile int yellowISRFlag = 0;
noutram 0:4e6cbb427cd7 22 volatile int greenISRFlag = 0;
noutram 0:4e6cbb427cd7 23
noutram 0:4e6cbb427cd7 24 //ON and OFF times
noutram 0:4e6cbb427cd7 25 // RED 9:1
noutram 0:4e6cbb427cd7 26 float TRedON = 0.009;
noutram 0:4e6cbb427cd7 27 float TRedOFF = 0.001;
noutram 0:4e6cbb427cd7 28 // YELLOW 1:1
noutram 0:4e6cbb427cd7 29 float TYellowON = 0.001;
noutram 0:4e6cbb427cd7 30 float TYellowOFF = 0.001;
noutram 0:4e6cbb427cd7 31 // GREEN 1:9 - nearly off
noutram 0:4e6cbb427cd7 32 float TGreenON = 0.001;
noutram 0:4e6cbb427cd7 33 float TGreenOFF = 0.009;
noutram 0:4e6cbb427cd7 34
noutram 0:4e6cbb427cd7 35 int main() {
noutram 0:4e6cbb427cd7 36 //Initialise the LEDs
noutram 0:4e6cbb427cd7 37 redLED = 0;
noutram 0:4e6cbb427cd7 38 yellowLED = 0;
noutram 0:4e6cbb427cd7 39 greenLED = 0;
noutram 0:4e6cbb427cd7 40
noutram 0:4e6cbb427cd7 41
noutram 0:4e6cbb427cd7 42 //Initialise timers (oneshot)
noutram 0:4e6cbb427cd7 43 tRed.attach(doRedPWM, TRedOFF);
noutram 0:4e6cbb427cd7 44 tYellow.attach(doYellowPWM, TYellowOFF);
noutram 0:4e6cbb427cd7 45 tGreen.attach(doGreenPWM, TGreenOFF);
noutram 0:4e6cbb427cd7 46
noutram 0:4e6cbb427cd7 47 while (1) {
noutram 0:4e6cbb427cd7 48 //Sleep and wait for an interrupt
noutram 0:4e6cbb427cd7 49 sleep();
noutram 0:4e6cbb427cd7 50
noutram 0:4e6cbb427cd7 51 //Chech which timer(s) went off
noutram 0:4e6cbb427cd7 52 if (redISRFlag == 1) {
noutram 0:4e6cbb427cd7 53 redISRFlag = 0; //Reset ISR flag
noutram 0:4e6cbb427cd7 54 float t = (redLED==0) ? TRedOFF : TRedON;
noutram 0:4e6cbb427cd7 55 tRed.attach(doRedPWM, t); //Reset timer
noutram 0:4e6cbb427cd7 56 }
noutram 0:4e6cbb427cd7 57 if (yellowISRFlag == 1) {
noutram 0:4e6cbb427cd7 58 yellowISRFlag = 0;
noutram 0:4e6cbb427cd7 59 float t = (yellowLED==0) ? TYellowOFF : TYellowON;
noutram 0:4e6cbb427cd7 60 tYellow.attach(doYellowPWM, t);
noutram 0:4e6cbb427cd7 61 }
noutram 0:4e6cbb427cd7 62 if (greenISRFlag == 1) {
noutram 0:4e6cbb427cd7 63 greenISRFlag = 0;
noutram 0:4e6cbb427cd7 64 float t = (greenLED==0) ? TGreenOFF : TGreenON;
noutram 0:4e6cbb427cd7 65 tGreen.attach(doGreenPWM, t);
noutram 0:4e6cbb427cd7 66 }
noutram 0:4e6cbb427cd7 67
noutram 0:4e6cbb427cd7 68 }
noutram 0:4e6cbb427cd7 69 }
noutram 0:4e6cbb427cd7 70
noutram 0:4e6cbb427cd7 71 void doRedPWM()
noutram 0:4e6cbb427cd7 72 {
noutram 0:4e6cbb427cd7 73 //Toggle LED
noutram 0:4e6cbb427cd7 74 redLED = !redLED;
noutram 0:4e6cbb427cd7 75 //Flag that interrupt has fired
noutram 0:4e6cbb427cd7 76 redISRFlag = 1;
noutram 0:4e6cbb427cd7 77
noutram 0:4e6cbb427cd7 78 }
noutram 0:4e6cbb427cd7 79 void doYellowPWM()
noutram 0:4e6cbb427cd7 80 {
noutram 0:4e6cbb427cd7 81 yellowLED = !yellowLED;
noutram 0:4e6cbb427cd7 82 yellowISRFlag = 1;
noutram 0:4e6cbb427cd7 83 }
noutram 0:4e6cbb427cd7 84 void doGreenPWM()
noutram 0:4e6cbb427cd7 85 {
noutram 0:4e6cbb427cd7 86 greenLED = !greenLED;
noutram 0:4e6cbb427cd7 87 greenISRFlag = 1;
noutram 0:4e6cbb427cd7 88 }