TaskScheduler.cpp

/***************************************************************************//**
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Copyright (c) 2017 Jon Knoll

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@file task_scheduler.cpp
@description see task_scheduler.h
*******************************************************************************/
#include "Arduino.h"
#include "TaskScheduler.h"


TaskScheduler::TaskScheduler(void)
{
   ts_taskBlockPtr = 0;
   ts_taskBlockSize = 0;
   ts_prevMs = 0;
}

// put this in setup()
void TaskScheduler::initialize(TaskBlock *taskBlockPtr, uint8_t numTasks)
{
   ts_taskBlockPtr = taskBlockPtr;
   ts_taskBlockSize = numTasks;
   ts_prevMs = millis();
}

// put this in loop()
void TaskScheduler::run(void)
{
   uint8_t i;
   TaskBlock *currentTaskPtr;
   uint32_t currentMs;
   uint32_t msDiff;
   
   currentMs = millis();
   msDiff = currentMs - ts_prevMs;
   
   for (i = 0; i < ts_taskBlockSize; i++)
   {
      currentTaskPtr = &ts_taskBlockPtr[i];
      
      if(currentTaskPtr->state == TASK_PEND)
      {
         if(currentTaskPtr->timer > 0)
         {
            if(currentTaskPtr->timer > msDiff)
            {
               currentTaskPtr->timer -= msDiff;
            }
            else
            {
               currentTaskPtr->timer = 0;
            }
         }

         if(currentTaskPtr->timer == 0)
         {
            currentTaskPtr->state = TASK_RUN;
         }
      }
      
      if(currentTaskPtr->state == TASK_RUN)
      {
         // task gets run here...
         currentTaskPtr->funcPtr();
         if(currentTaskPtr->state == TASK_RUN)
         {
            // if the current task is still set to run (it did not put
            // itself to sleep) then it is done running for now.
            currentTaskPtr->state = TASK_STOP;
         }
      }
   }
   ts_prevMs = currentMs;
}

void TaskScheduler::sleep(uint8_t taskId, uint16_t ms)
{
   if(ts_taskBlockPtr[taskId].state != TASK_OFF)
   {
      ts_taskBlockPtr[taskId].state = TASK_PEND;
   }
   ts_taskBlockPtr[taskId].timer = ms;
}

void TaskScheduler::setEntryPoint(uint8_t taskId, TaskFuncPtr newFuncPtr)
{
   ts_taskBlockPtr[taskId].funcPtr = newFuncPtr;
}

TaskState TaskScheduler::getState(uint8_t taskId)
{
   return(ts_taskBlockPtr[taskId].state);
}

void TaskScheduler::setState(uint8_t taskId, TaskState newState)
{
   ts_taskBlockPtr[taskId].state = newState;
}