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/* ---------------------------------------------------------------------------- */
/* Atmel Microcontroller Software Support */
/* SAM Software Package License */
/* ---------------------------------------------------------------------------- */
/* Copyright (c) 2015, Atmel Corporation */
/* */
/* All rights reserved. */
/* */
/* Redistribution and use in source and binary forms, with or without */
/* modification, are permitted provided that the following condition is met: */
/* */
/* - Redistributions of source code must retain the above copyright notice, */
/* this list of conditions and the disclaimer below. */
/* */
/* Atmel's name may not be used to endorse or promote products derived from */
/* this software without specific prior written permission. */
/* */
/* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR */
/* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE */
/* DISCLAIMED. IN NO EVENT SHALL ATMEL 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. */
/* ---------------------------------------------------------------------------- */
/**
* \file
*
* Implementation of Watchdog Timer (WDT) controller.
*
*/
/** \addtogroup wdt_module Working with WDT
* \ingroup peripherals_module
* The WDT driver provides the interface to configure and use the WDT
* peripheral.
*
* The WDT can be used to prevent system lock-up if the software becomes
* trapped in a deadlock. It can generate a general reset or a processor
* reset only. It is clocked by slow clock divided by 128.
*
* The WDT is running at reset with 16 seconds watchdog period (slow clock at
* 32.768 kHz)
* and external reset generation enabled. The user must either disable it or
* reprogram it to meet the application requires.
*
* To use the WDT, the user could follow these few steps:
* <ul>
* <li>Enable watchdog with given mode using \ref WDT_Enable().
* <li>Restart the watchdog using \ref WDT_Restart() within the watchdog period.
* </ul>
*
* For more accurate information, please look at the WDT section of the
* Datasheet.
*
* \note
* The Watchdog Mode Register (WDT_MR) can be written only once.\n
*
* Related files :\n
* \ref wdt.c\n
* \ref wdt.h.\n
*/
/*@{*/
/*@}*/
/*---------------------------------------------------------------------------
* Headers
*---------------------------------------------------------------------------*/
#include "chip.h"
#include <stdint.h>
/*----------------------------------------------------------------------------
* Exported functions
*----------------------------------------------------------------------------*/
/**
* \brief Enable watchdog with given mode.
*
* \note The Watchdog Mode Register (WDT_MR) can be written only once.
* Only a processor reset resets it.
*
* \param dwMode WDT mode to be set
*/
extern void WDT_Enable(Wdt *pWDT, uint32_t dwMode)
{
pWDT->WDT_MR = dwMode;
}
/**
* \brief Disable watchdog.
*
* \note The Watchdog Mode Register (WDT_MR) can be written only once.
* Only a processor reset resets it.
*/
extern void WDT_Disable(Wdt *pWDT)
{
pWDT->WDT_MR = WDT_MR_WDDIS;
}
/**
* \brief Watchdog restart.
*/
extern void WDT_Restart(Wdt *pWDT)
{
pWDT->WDT_CR = 0xA5000001;
}
/**
* \brief Watchdog get status.
*/
extern uint32_t WDT_GetStatus(Wdt *pWDT)
{
return (pWDT->WDT_SR & 0x3);
}
/**
* \brief Watchdog get period.
*
* \param dwMs desired watchdog period in millisecond.
*/
extern uint32_t WDT_GetPeriod(uint32_t dwMs)
{
if ((dwMs < 4) || (dwMs > 16000))
return 0;
return ((dwMs << 8) / 1000);
}
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