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/* ----------------------------------------------------------------------------
* ATMEL Microcontroller Software Support
* ----------------------------------------------------------------------------
* Copyright (c) 2011, Atmel Corporation
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are 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
* 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) ;
}