nes-proj/cpu/msp430/watchdog.c

81 lines
2.9 KiB
C

/*
* Copyright (c) 2005, Swedish Institute of Computer Science
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* @(#)$Id: watchdog.c,v 1.5 2008/02/11 10:45:19 adamdunkels Exp $
*/
#include <io.h>
#include "dev/watchdog.h"
static int stopped = 0;
/*---------------------------------------------------------------------------*/
void
watchdog_init(void)
{
/* The MSP430 watchdog is enabled at boot-up, so we stop it during
initialization. */
stopped = 0;
watchdog_stop();
}
/*---------------------------------------------------------------------------*/
void
watchdog_start(void)
{
/* We setup the watchdog to reset the device after one second,
unless watchdog_periodic() is called. */
stopped--;
if(!stopped) {
WDTCTL = WDTPW | WDTCNTCL | WDT_ARST_1000;
}
}
/*---------------------------------------------------------------------------*/
void
watchdog_periodic(void)
{
/* This function is called periodically to restart the watchdog
timer. */
if(!stopped) {
WDTCTL = (WDTCTL & 0xff) | WDTPW | WDTCNTCL;
}
}
/*---------------------------------------------------------------------------*/
void
watchdog_stop(void)
{
WDTCTL = WDTPW | WDTHOLD;
stopped++;
}
/*---------------------------------------------------------------------------*/
void
watchdog_reboot(void)
{
WDTCTL = 0;
}
/*---------------------------------------------------------------------------*/