st79_wwdg.c

st公司新出的一款8位单片机st79的lib库

/**
  ********************************************************************************
  * @file st79_wwdg.c
  * @brief This file contains all the functions for the WWDG peripheral.
  * @author STMicroelectronics - MCD & APG Car Body Application Labs
  * @version V0.01
  * @date 04-JUL-2007
  ******************************************************************************
  *
  * THE PRESENT SOFTWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  *
  * <h2><center>&copy; COPYRIGHT 2007 STMicroelectronics</center></h2>
  * @image html logo.bmp
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "st79_wwdg.h"

/* LINKER SECTIONS DEFINITION FOR THIS FILE ONLY */
#pragma section (WWDG_CODE)
#pragma section const {WWDG_CONST}
#pragma section @near [WWDG_URAM]
#pragma section @near {WWDG_IRAM}
#pragma section @tiny [WWDG_UZRAM]
#pragma section @tiny {WWDG_IZRAM}

/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
/* Public functions ----------------------------------------------------------*/

/** @addtogroup WWDG_Public_Functions
  * @{
  */

/**
  * @brief Initialization of the WWDG peripheral.
  *  This function set Window Register = WindowLimitValue,
  *  Control Register according to ControlValue and \b ENABLE \b WDG*
  * @par Full description:
  * @param[in] ControlValue - WWDG Control Register
  * @param[in] WindowLimitValue - WWDG Window Register, range is 0x00 to 0x7F.
  * @retval
  * void None
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Example:
  * This example shows how to call the function:
  * @code
  * Enable write access to Prescaler and Reload registers
  * WWDG_Init(0xFF, 0x70);
  * @endcode
  */
void WWDG_Init(u8 ControlValue, u8 WindowLimitValue)
{
  /* Check the parameters */
  assert(IS_WWDG_WINDOWLIMITVALUE_OK(WindowLimitValue));
  WWDG->WR = WWDG_WR_RESET_VALUE;
  WWDG->CR = WWDG_CR_WDGA | WWDG_CR_T6 | ControlValue;
  WWDG->WR = (u8)(~WWDG_CR_WDGA) & (WWDG_CR_T6 | WindowLimitValue);
}

/**
  * @brief Refresh of the WWDG peripheral.
  * This function has no effect out of Refresh Window
  * @par Full description:
  * @param[in] CounterValue - WWDG Counter Value
  * @retval
  * void None
  * @par Required preconditions:
  * Required preconditions: \b Counter < \b Window \b Limit \n
  * @par Called functions:
  * None
  * @par Example:
  * This example shows how to call the function:
  * @code
  * WWDG_Refresh(0xFF);
  * @endcode
  */
void WWDG_Refresh(u8 CounterValue)
{
  /* Check the parameters */
  assert(IS_WWDG_COUNTERVALUE_OK(CounterValue));
  if ((WWDG->CR & (u8)(~WWDG_CR_WDGA)) < (WWDG->WR))
  {
    WWDG->CR = WWDG_CR_WDGA | WWDG_CR_T6 | CounterValue;
  }
}

/**
  * @brief Read of the WWDG Control Register.
  * This value could be used to check if WWDG is in the window, where refresh is allowed.
  * @par Full description:
  * None
  * @retval
  * u8 Control Register
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Examples:
  * This example shows how to call the function:
  * @code
  * Watchdog_Value = WWDG_GetControlValue();
  * @endcode
  */
u8 WWDG_GetControlValue(void)
{
  return(WWDG->CR);
}

/**
  * @brief Generates immediate SW RESET, using the WWDG peripheral.
  * @par Full description:
  * None
  * @retval
  * void None
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Examples:
  * This example shows how to call the function:
  * @code
  * WWDG_SWReset();
  * @endcode
  */
void WWDG_SWReset(void)
{
  WWDG->CR = WWDG_CR_WDGA; /*activate WWDG, with clearing T6*/
}

/**
  * @}
  */

/******************* (C) COPYRIGHT 2007 STMicroelectronics *****END OF FILE****/