ref: 01af5a89b3e1ac5c45472ef8ade9c15ffbd19925
dir: /demos/stm32f429_disco/stm/stm32f4_spl/src/stm32f4xx_hal_wwdg.c/
/**
******************************************************************************
* @file stm32f4xx_hal_wwdg.c
* @author MCD Application Team
* @version V1.0.0
* @date 18-February-2014
* @brief WWDG HAL module driver.
* This file provides firmware functions to manage the following
* functionalities of the Window Watchdog (WWDG) peripheral:
* + Initialization and de-initialization functions
* + IO operation functions
* + Peripheral State functions
@verbatim
==============================================================================
##### WWDG specific features #####
==============================================================================
[..]
Once enabled the WWDG generates a system reset on expiry of a programmed
time period, unless the program refreshes the counter (downcounter)
before reaching 0x3F value (i.e. a reset is generated when the counter
value rolls over from 0x40 to 0x3F).
(+) An MCU reset is also generated if the counter value is refreshed
before the counter has reached the refresh window value. This
implies that the counter must be refreshed in a limited window.
(+) Once enabled the WWDG cannot be disabled except by a system reset.
(+) WWDGRST flag in RCC_CSR register can be used to inform when a WWDG
reset occurs.
(+) The WWDG counter input clock is derived from the APB clock divided
by a programmable prescaler.
(+) WWDG clock (Hz) = PCLK1 / (4096 * Prescaler)
(+) WWDG timeout (mS) = 1000 * Counter / WWDG clock
(+) WWDG Counter refresh is allowed between the following limits :
(++) min time (mS) = 1000 * (Counter � Window) / WWDG clock
(++) max time (mS) = 1000 * (Counter � 0x40) / WWDG clock
(+) Min-max timeout value at 50 MHz(PCLK1): 81.9 us / 41.9 ms
##### How to use this driver #####
==============================================================================
[..]
(+) Enable WWDG APB1 clock using __WWDG_CLK_ENABLE().
(+) Set the WWDG prescaler, refresh window and counter value
using HAL_WWDG_Init() function.
(+) Start the WWDG using HAL_WWDG_Start() function.
When the WWDG is enabled the counter value should be configured to
a value greater than 0x40 to prevent generating an immediate reset.
(+) Optionally you can enable the Early Wakeup Interrupt (EWI) which is
generated when the counter reaches 0x40, and then start the WWDG using
HAL_WWDG_Start_IT(). At EWI HAL_WWDG_WakeupCallback is executed and user can
add his own code by customization of function pointer HAL_WWDG_WakeupCallback
Once enabled, EWI interrupt cannot be disabled except by a system reset.
(+) Then the application program must refresh the WWDG counter at regular
intervals during normal operation to prevent an MCU reset, using
HAL_WWDG_Refresh() function. This operation must occur only when
the counter is lower than the refresh window value already programmed.
*** WWDG HAL driver macros list ***
==================================
[..]
Below the list of most used macros in WWDG HAL driver.
(+) __HAL_WWDG_ENABLE: Enable the WWDG peripheral
(+) __HAL_IWDG_GET_FLAG: Get the selected WWDG's flag status
(+) __HAL_IWDG_CLEAR_FLAG: Clear the WWDG's pending flags
(+) __HAL_IWDG_RELOAD_COUNTER: Enables the WWDG early wakeup interrupt
@endverbatim
******************************************************************************
* @attention
*
* <h2><center>© COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
*
* 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 STMicroelectronics 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx_hal.h"
/** @addtogroup STM32F4xx_HAL_Driver
* @{
*/
/** @defgroup WWDG
* @brief WWDG HAL module driver.
* @{
*/
#ifdef HAL_WWDG_MODULE_ENABLED
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
/** @defgroup WWDG_Private_Functions
* @{
*/
/** @defgroup WWDG_Group1 Initialization and de-initialization functions
* @brief Initialization and Configuration functions.
*
@verbatim
==============================================================================
##### Initialization and de-initialization functions #####
==============================================================================
[..]
This section provides functions allowing to:
(+) Initialize the WWDG according to the specified parameters
in the WWDG_InitTypeDef and create the associated handle
(+) DeInitialize the WWDG peripheral
(+) Initialize the WWDG MSP
(+) DeInitialize the WWDG MSP
@endverbatim
* @{
*/
/**
* @brief Initializes the WWDG according to the specified
* parameters in the WWDG_InitTypeDef and creates the associated handle.
* @param hwwdg: WWDG handle
* @retval HAL status
*/
HAL_StatusTypeDef HAL_WWDG_Init(WWDG_HandleTypeDef *hwwdg)
{
uint32_t tmp = 0;
/* Check the WWDG handle allocation */
if(hwwdg == NULL)
{
return HAL_ERROR;
}
/* Check the parameters */
assert_param(IS_WWDG_PRESCALER(hwwdg->Init.Prescaler));
assert_param(IS_WWDG_WINDOW(hwwdg->Init.Window));
assert_param(IS_WWDG_COUNTER(hwwdg->Init.Counter));
if(hwwdg->State == HAL_WWDG_STATE_RESET)
{
/* Init the low level hardware */
HAL_WWDG_MspInit(hwwdg);
}
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_BUSY;
/* Set WWDG Prescaler and Window */
/* Get the CFR register value */
tmp = hwwdg->Instance->CFR;
/* Clear WDGTB[1:0] and W[6:0] bits */
tmp &= ((uint32_t)~(WWDG_CFR_WDGTB | WWDG_CFR_W));
/* Prepare the WWDG Prescaler and Window parameters */
tmp |= hwwdg->Init.Prescaler | hwwdg->Init.Window;
/* Write to WWDG CFR */
hwwdg->Instance->CFR = tmp;
/* Set WWDG Counter */
/* Get the CR register value */
tmp = hwwdg->Instance->CR;
/* Clear T[6:0] bits */
tmp &= ((uint32_t)~(WWDG_CR_T));
/* Prepare the WWDG Counter parameter */
tmp |= (hwwdg->Init.Counter);
/* Write to WWDG CR */
hwwdg->Instance->CR = tmp;
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_READY;
/* Return function status */
return HAL_OK;
}
/**
* @brief DeInitializes the WWDG peripheral.
* @param hwwdg: WWDG handle
* @retval HAL status
*/
HAL_StatusTypeDef HAL_WWDG_DeInit(WWDG_HandleTypeDef *hwwdg)
{
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_BUSY;
/* DeInit the low level hardware */
HAL_WWDG_MspDeInit(hwwdg);
/* Reset WWDG Control register */
hwwdg->Instance->CR = (uint32_t)0x0000007F;
/* Reset WWDG Configuration register */
hwwdg->Instance->CFR = (uint32_t)0x0000007F;
/* Reset WWDG Status register */
hwwdg->Instance->SR = 0;
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_RESET;
/* Release Lock */
__HAL_UNLOCK(hwwdg);
/* Return function status */
return HAL_OK;
}
/**
* @brief Initializes the WWDG MSP.
* @param hwwdg: WWDG handle
* @retval None
*/
__weak void HAL_WWDG_MspInit(WWDG_HandleTypeDef *hwwdg)
{
/* NOTE: This function Should not be modified, when the callback is needed,
the HAL_WWDG_MspInit could be implemented in the user file
*/
}
/**
* @brief DeInitializes the WWDG MSP.
* @param hwwdg: WWDG handle
* @retval None
*/
__weak void HAL_WWDG_MspDeInit(WWDG_HandleTypeDef *hwwdg)
{
/* NOTE: This function Should not be modified, when the callback is needed,
the HAL_WWDG_MspDeInit could be implemented in the user file
*/
}
/**
* @}
*/
/** @defgroup WWDG_Group2 IO operation functions
* @brief IO operation functions
*
@verbatim
==============================================================================
##### IO operation functions #####
==============================================================================
[..]
This section provides functions allowing to:
(+) Start the WWDG.
(+) Refresh the WWDG.
(+) Handle WWDG interrupt request.
@endverbatim
* @{
*/
/**
* @brief Starts the WWDG.
* @param hwwdg: WWDG handle
* @retval HAL status
*/
HAL_StatusTypeDef HAL_WWDG_Start(WWDG_HandleTypeDef *hwwdg)
{
/* Process Locked */
__HAL_LOCK(hwwdg);
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_BUSY;
/* Enable the peripheral */
__HAL_WWDG_ENABLE(hwwdg);
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_READY;
/* Process Unlocked */
__HAL_UNLOCK(hwwdg);
/* Return function status */
return HAL_OK;
}
/**
* @brief Starts the WWDG with interrupt enabled.
* @param hwwdg: WWDG handle
* @retval HAL status
*/
HAL_StatusTypeDef HAL_WWDG_Start_IT(WWDG_HandleTypeDef *hwwdg)
{
/* Process Locked */
__HAL_LOCK(hwwdg);
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_BUSY;
/* Enable the Early Wakeup Interrupt */
__HAL_WWDG_ENABLE_IT(WWDG_IT_EWI);
/* Enable the peripheral */
__HAL_WWDG_ENABLE(hwwdg);
/* Return function status */
return HAL_OK;
}
/**
* @brief Refreshes the WWDG.
* @param hwwdg: WWDG handle
* @retval HAL status
*/
HAL_StatusTypeDef HAL_WWDG_Refresh(WWDG_HandleTypeDef *hwwdg, uint32_t Counter)
{
/* Process Locked */
__HAL_LOCK(hwwdg);
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_BUSY;
/* Check the parameters */
assert_param(IS_WWDG_COUNTER(Counter));
/* Write to WWDG CR the WWDG Counter value to refresh with */
MODIFY_REG(hwwdg->Instance->CR, WWDG_CR_T, Counter);
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_READY;
/* Process Unlocked */
__HAL_UNLOCK(hwwdg);
/* Return function status */
return HAL_OK;
}
/**
* @brief Handles WWDG interrupt request.
* @note The Early Wakeup Interrupt (EWI) can be used if specific safety operations
* or data logging must be performed before the actual reset is generated.
* The EWI interrupt is enabled using __HAL_WWDG_ENABLE_IT() macro.
* When the downcounter reaches the value 0x40, and EWI interrupt is
* generated and the corresponding Interrupt Service Routine (ISR) can
* be used to trigger specific actions (such as communications or data
* logging), before resetting the device.
* @param hwwdg: WWDG handle
* @retval None
*/
void HAL_WWDG_IRQHandler(WWDG_HandleTypeDef *hwwdg)
{
/* WWDG Early Wakeup Interrupt occurred */
if(__HAL_WWDG_GET_FLAG(hwwdg, WWDG_FLAG_EWIF) != RESET)
{
/* Early Wakeup callback */
HAL_WWDG_WakeupCallback(hwwdg);
/* Change WWDG peripheral state */
hwwdg->State = HAL_WWDG_STATE_READY;
/* Clear the WWDG Data Ready flag */
__HAL_WWDG_CLEAR_FLAG(hwwdg, WWDG_FLAG_EWIF);
/* Process Unlocked */
__HAL_UNLOCK(hwwdg);
}
}
/**
* @brief Early Wakeup WWDG callback.
* @param hwwdg: WWDG handle
* @retval None
*/
__weak void HAL_WWDG_WakeupCallback(WWDG_HandleTypeDef* hwwdg)
{
/* NOTE: This function Should not be modified, when the callback is needed,
the HAL_WWDG_WakeupCallback could be implemented in the user file
*/
}
/**
* @}
*/
/** @defgroup WWDG_Group3 Peripheral State functions
* @brief Peripheral State functions.
*
@verbatim
==============================================================================
##### Peripheral State functions #####
==============================================================================
[..]
This subsection permits to get in run-time the status of the peripheral
and the data flow.
@endverbatim
* @{
*/
/**
* @brief Returns the WWDG state.
* @param hwwdg: WWDG handle
* @retval HAL state
*/
HAL_WWDG_StateTypeDef HAL_WWDG_GetState(WWDG_HandleTypeDef *hwwdg)
{
return hwwdg->State;
}
/**
* @}
*/
/**
* @}
*/
#endif /* HAL_WWDG_MODULE_ENABLED */
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/