PIT.c

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#include "Compile_Options.h"
#include "derivative.h"
//#include "utils.h" /* For Copy Array */
#include "PIT.h"
/*
 ******************************************************************************
 * constants
 ******************************************************************************
 */
 /*
 ******************************************************************************
 * Globals
 ******************************************************************************
 */
/*
 ******************************************************************************
 * u8fnPITConfig
 ******************************************************************************
 */
uint8_t u8fnPITConfig(const uint8_t u8Channel, 
                      const uint32_t u32InitialCount,
                      const uint8_t u8UseISR)
{
  /* Local variables */
  uint8_t u8Status;
  
  u8Status = CLEAR;
  
  /* Make sure that the module is enabled before any configuration is done   */
  PIT.PITMCR.B.MDIS = CLEAR;
  
  /* Also, make sure that the particular channel exists */
  if(N_PIT_CHANNELS > u8Channel)
  {
    /* Make sure that the particular channel we're configuring is off        */
    PIT.CH[u8Channel].TCTRL.B.TEN = CLEAR;
    
    /* Load the number of counts before the timer expires - we are always    */
    /* using the system clock.                                               */
    PIT.CH[u8Channel].LDVAL.R = u32InitialCount;
  
    /* Clear any pending flags */
    PIT.CH[u8Channel].TFLG.R = TRUE;
  
    /* Set interrupts */
    PIT.CH[u8Channel].TCTRL.B.TIE = (CLEAR < u8UseISR);
  }
  else
  {
    /* Not a valid channel */
    u8Status = PIT_INVALID_CH;
  }
  
  return(u8Status);
}
/*
 ******************************************************************************
 * vfnPITStart
 ******************************************************************************
 */
void vfnPITStart(const uint8_t u8Channel, const uint8_t u8Enable)
{
  PIT.CH[u8Channel].TCTRL.B.TEN = (CLEAR < u8Enable);
  return;
}
/*
 ******************************************************************************
 * u8fnPITWaitByPoll
 ******************************************************************************
 */
uint8_t u8fnPITWaitByPoll(const uint8_t u8Channel, const uint8_t u8Restart)
{
  /* Locals */
  uint8_t  u8Status;
  uint32_t u32TimeOut;
  
  /* Init */
  u8Status   = CLEAR;
  u32TimeOut = PIT.CH[u8Channel].LDVAL.R;
  
  /* Wait for it */
  do
  {
    u32TimeOut--;
  }while((u32TimeOut != CLEAR) && (PIT.CH[u8Channel].TFLG.R == CLEAR));
  
  if(CLEAR == u32TimeOut)
  {
    /* We timed-out. Not good */
    u8Status = PIT_ERROR_TIMED_OUT;
  }
  else
  {
    /* It's probably a good idea to clear the flag */
    PIT.CH[u8Channel].TFLG.B.TIF = TRUE;
    
    /* And depending on the passed argument, restart the PIT */
    if(CLEAR != u8Restart)
    {
      /* PIT already counting down again */
    }
    else
    {
      vfnPITStart(u8Channel, CLEAR);
    }
  }
  
  return(u8Status);
}
    
/*
 ******************************************************************************
 *
 *  End of file.
 *
 ******************************************************************************
 */