University of Plymouth - Stages 1, 2 and 3 / Mbed OS Task617Solution-mbedos-FZ429

Solution to the deadlock problem

Fork of Task617Solution-mbedos54 by Nicholas Outram

main.cpp@7:bd75e7717b58, 2017-10-31 (annotated)

Committer:
noutram
Date:
Tue Oct 31 15:40:25 2017 +0000
Revision:
7:bd75e7717b58
Parent:
6:d16ce38e9b8a 
updated for stage-3

Who changed what in which revision?

UserRevisionLine numberNew contents of line
noutram 0:f916cefba2f4 1 #include "mbed.h"
noutram 0:f916cefba2f4 2 #include "rtos.h"
noutram 2:70084af839d3 3 #include "string.h"
noutram 2:70084af839d3 4 #include <stdio.h>
noutram 2:70084af839d3 5 #include <ctype.h>
noutram 0:f916cefba2f4 6
noutram 4:dae8898e55fe 7 #define DELAY 200
noutram 0:f916cefba2f4 8
noutram 0:f916cefba2f4 9 DigitalOut onBoardLED(LED1);
noutram 7:bd75e7717b58 10 DigitalOut redLED(PE_15);
noutram 7:bd75e7717b58 11 DigitalOut yellowLED(PB_10);
noutram 7:bd75e7717b58 12 DigitalOut greenLED(PB_11);
noutram 0:f916cefba2f4 13
noutram 0:f916cefba2f4 14 DigitalIn onBoardSwitch(USER_BUTTON);
noutram 7:bd75e7717b58 15 DigitalIn SW1(PE_12);
noutram 7:bd75e7717b58 16 DigitalIn SW2(PE_14);
noutram 0:f916cefba2f4 17
noutram 0:f916cefba2f4 18 //Thread ID for the Main function (CMSIS API)
noutram 0:f916cefba2f4 19 osThreadId tidMain;
noutram 0:f916cefba2f4 20
noutram 2:70084af839d3 21 //Thread sychronisation primatives
noutram 4:dae8898e55fe 22 Mutex lock1;
noutram 4:dae8898e55fe 23 Mutex lock2;
noutram 4:dae8898e55fe 24 unsigned long sw1Count = 0;
noutram 4:dae8898e55fe 25 unsigned long sw2Count = 0;
noutram 2:70084af839d3 26
noutram 6:d16ce38e9b8a 27 void thread1()
noutram 4:dae8898e55fe 28 {
noutram 7:bd75e7717b58 29 printf("Entering thread 1\n");
noutram 4:dae8898e55fe 30 while (true) {
noutram 5:31707531f715 31 yellowLED = 1;
noutram 4:dae8898e55fe 32
noutram 4:dae8898e55fe 33 //Start critical section
noutram 4:dae8898e55fe 34 lock1.lock();
noutram 4:dae8898e55fe 35
noutram 4:dae8898e55fe 36 sw1Count++;
noutram 4:dae8898e55fe 37 printf("\nCount1 = %lu", sw1Count);
noutram 4:dae8898e55fe 38
noutram 5:31707531f715 39 Thread::wait(1); //1ms
noutram 4:dae8898e55fe 40
noutram 4:dae8898e55fe 41 //End critical section
noutram 4:dae8898e55fe 42 lock1.unlock();
noutram 5:31707531f715 43
noutram 5:31707531f715 44 if (SW1 == 1) {
noutram 5:31707531f715 45 lock2.lock();
noutram 5:31707531f715 46 sw2Count--;
noutram 5:31707531f715 47 lock2.unlock();
noutram 5:31707531f715 48 }
noutram 4:dae8898e55fe 49
noutram 5:31707531f715 50 yellowLED = 0;
noutram 4:dae8898e55fe 51 Thread::wait(DELAY);
noutram 4:dae8898e55fe 52 }
noutram 2:70084af839d3 53 }
noutram 2:70084af839d3 54
noutram 6:d16ce38e9b8a 55 void thread2()
noutram 0:f916cefba2f4 56 {
noutram 7:bd75e7717b58 57 printf("Entering thread 2\n");
noutram 2:70084af839d3 58 while (true) {
noutram 5:31707531f715 59 redLED = 1;
noutram 2:70084af839d3 60
noutram 4:dae8898e55fe 61 //Start critical section
noutram 4:dae8898e55fe 62 lock2.lock();
noutram 2:70084af839d3 63
noutram 4:dae8898e55fe 64 sw2Count++;
noutram 4:dae8898e55fe 65 printf("\nCount2 = %lu", sw2Count);
noutram 4:dae8898e55fe 66
noutram 5:31707531f715 67 Thread::wait(1); //1ms
noutram 1:4fb27aea76b2 68
noutram 5:31707531f715 69 //End critical section
noutram 5:31707531f715 70 lock2.unlock();
noutram 5:31707531f715 71
noutram 5:31707531f715 72 if (SW2 == 1) {
noutram 4:dae8898e55fe 73 lock1.lock();
noutram 4:dae8898e55fe 74 sw1Count--;
noutram 4:dae8898e55fe 75 lock1.unlock();
noutram 4:dae8898e55fe 76 }
noutram 5:31707531f715 77
noutram 5:31707531f715 78 redLED = 0;
noutram 5:31707531f715 79 Thread::wait(DELAY);
noutram 1:4fb27aea76b2 80
noutram 4:dae8898e55fe 81 }
noutram 0:f916cefba2f4 82 }
noutram 0:f916cefba2f4 83
noutram 4:dae8898e55fe 84
noutram 0:f916cefba2f4 85 //Main thread
noutram 0:f916cefba2f4 86 int main() {
noutram 0:f916cefba2f4 87 redLED = 0;
noutram 0:f916cefba2f4 88 yellowLED = 0;
noutram 2:70084af839d3 89 greenLED = 0;
noutram 4:dae8898e55fe 90
noutram 0:f916cefba2f4 91 //Main thread ID
noutram 0:f916cefba2f4 92 tidMain = Thread::gettid();
noutram 0:f916cefba2f4 93
noutram 4:dae8898e55fe 94 //Threads
noutram 6:d16ce38e9b8a 95 Thread t1, t2;
noutram 6:d16ce38e9b8a 96
noutram 6:d16ce38e9b8a 97 t1.start(thread1);
noutram 6:d16ce38e9b8a 98 t2.start(thread2);
noutram 1:4fb27aea76b2 99
noutram 7:bd75e7717b58 100 printf("Main Thread\n");
noutram 2:70084af839d3 101 while (true) {
noutram 4:dae8898e55fe 102 Thread::wait(osWaitForever);
noutram 0:f916cefba2f4 103 }
noutram 0:f916cefba2f4 104
noutram 0:f916cefba2f4 105 }
noutram 2:70084af839d3 106
noutram 2:70084af839d3 107