int OS_AddThread(void(*task)(void), unsigned long stackSize, unsigned long priority)
{
uint32_t status;
status = OS_StartCritical();
//we will take the first thread from the dead pool
if(DeadPt == '\0')
{
OS_DisableInterrupts();
while(1){}
}
(DeadPt)->id = uniqueId; //unique id
(DeadPt)->active = 1;
(DeadPt)->sleepState = 0; //flag
(DeadPt)->priority = priority;
(DeadPt)->blockedState = 0; //flag
(DeadPt)->needToWakeUp = 0; //flag
SetInitialStack(DeadPt, stackSize);
(DeadPt)->stack[stackSize - 2] = (uint32_t)task; //push PC
uniqueId++;
addDeadToScheduler(&DeadPt);
if(higherPriorityAdded == 1)
{
OS_Suspend();
}
OS_EndCritical(status);
return 1;
}
// ******** OS_Wait ************
// decrement semaphore
// Lab2 spinlock
// Lab3 block if less than zero
// input: pointer to a counting semaphore
// output: none
void OS_Wait(Sema4Type *semaPt)
{
uint32_t status;
status = OS_StartCritical();
(*semaPt).Value--; //decrease count
if((*semaPt).Value < 0)
{
OS_Block(semaPt); //block and put into semaphore blocked list
OS_Suspend();
OS_EnableInterrupts();
OS_DisableInterrupts();
}
OS_EndCritical(status);
}
CANmsgType BCAN_get(void)
{
long sr;
CANmsgType data;
OS_Wait(&CANmessagesReceived);
sr = OS_StartCritical();
while(!CAN_RX_FIFOFifo_Get(&data)) //keep checking if the FIFO has data
{
#ifdef OS_COOP_SPINLOCK //if the interrupt fires and stuffs the FIFO
OS_Suspend(); //before the systick triggers a threadswitch
#endif //it will get its data faster (but other threads will have to wait)
}
OS_EndCritical(sr);
return data;
}
//this will be run by the time set in OS_Launch
//Right now initialized to 1ms
//ASSUMING .5 MS UNITS FOR PERIODIC THREADS
void Timer1A_Handler(){
TIMER1_ICR_R = TIMER_ICR_TATOCINT; // acknowledge timer1A timeout
int32_t status;
status = OS_StartCritical();
//need to traverse linked list of peridoc threads
struct PeriodicThread * tempTraversal = PeriodPt;
if(PeriodPt != '\0') //at least one periodic thread has been added
{
while(tempTraversal != '\0')
{
(*tempTraversal).timeLeft --; //decrease 1ms
if((*tempTraversal).timeLeft == 0) //need to run!
{
(*tempTraversal).timeLeft = (*tempTraversal).period; //reset time left
(*(*tempTraversal).task)(); //run the task
}
tempTraversal = (*tempTraversal).nextPeriodicThread; //finished running or checking, go to next node
}
}
OS_EndCritical(status);
}