wdt.c

NXP LPC系列AMR7的开发程序源码（LCD

/*****************************************************************************
 *   wdt.c:  Watchdog C file for NXP LPC23xx/24xx Family Microprocessors
 *
 *   Copyright(C) 2006, NXP Semiconductor
 *   All rights reserved.
 *
 *   History
 *   2006.07.20  ver 1.00    Prelimnary version, first Release
 *
*****************************************************************************/
#include <nxp/iolpc2468.h>
#include "type.h"
#include "irq.h"
#include "timer.h"
#include "wdt.h"

#include <intrinsics.h>

volatile DWORD wdt_counter;

/*****************************************************************************
** Function name:   WDTHandler
**
** Descriptions:    Watchdog timer interrupt handler
**
** parameters:      None
** Returned value:    None
**
*****************************************************************************/
__irq __nested __arm void WDTHandler (void)
{
  WDMOD &= ~WDTOF;    /* clear the time-out interrupt flag */

  __enable_interrupt(); /* handles nested interrupt */

  wdt_counter++;

  VICADDRESS = 0;   /* Acknowledge Interrupt */
}

/*****************************************************************************
** Function name:   WDTInit
**
** Descriptions:    Initialize watchdog timer, install the
**        watchdog timer interrupt handler
**
** parameters:      None
** Returned value:    true or false, return false if the VIC table
**        is full and WDT interrupt handler can be
**        installed.
**
*****************************************************************************/
DWORD WDTInit( void )
{
  wdt_counter = 0;
  if ( install_irq( WDT_INT, (void *)WDTHandler, HIGHEST_PRIORITY ) == FALSE )
  {
    return (FALSE);
  }

  WDTC = WDT_FEED_VALUE;  /* once WDEN is set, the WDT will start after feeding */
  WDMOD = WDEN | WDRESET;

  WDFEED = 0xAA;    /* Feeding sequence */
  WDFEED = 0x55;
  return( TRUE );
}

/*****************************************************************************
** Function name:   WDTFeed
**
** Descriptions:    Feed watchdog timer to prevent it from timeout
**
** parameters:      None
** Returned value:    None
**
*****************************************************************************/
void WDTFeed( void )
{
  WDFEED = 0xAA;    /* Feeding sequence */
  WDFEED = 0x55;
  return;
}

/******************************************************************************
**                            End Of File
******************************************************************************/