int/com/lib/STM32F7xx_HAL_Driver/Src/stm32f7xx_hal_wwdg.c

   1 /**
   2   ******************************************************************************
   3   * @file    stm32f7xx_hal_wwdg.c
   4   * @author  MCD Application Team
   5   * @version V1.1.0
   6   * @date    22-April-2016
   7   * @brief   WWDG HAL module driver.
   8   *          This file provides firmware functions to manage the following
   9   *          functionalities of the Window Watchdog (WWDG) peripheral:
  10   *           + Initialization and Configuration function
  11   *           + IO operation functions
  12   @verbatim
  13   ==============================================================================
  14                       ##### WWDG specific features #####
  15   ==============================================================================
  16   [..]
  17     Once enabled the WWDG generates a system reset on expiry of a programmed
  18     time period, unless the program refreshes the counter (T[6;0] downcounter)
  19     before reaching 0x3F value (i.e. a reset is generated when the counter
  20     value rolls over from 0x40 to 0x3F).
  21
  22     (+) An MCU reset is also generated if the counter value is refreshed
  23         before the counter has reached the refresh window value. This
  24         implies that the counter must be refreshed in a limited window.
  25
  26     (+) Once enabled the WWDG cannot be disabled except by a system reset.
  27
  28     (+) WWDGRST flag in RCC_CSR register informs when a WWDG reset has
  29         occurred (check available with __HAL_RCC_GET_FLAG(RCC_FLAG_WWDGRST)).
  30
  31     (+) The WWDG downcounter input clock is derived from the APB clock divided
  32         by a programmable prescaler.
  33
  34     (+) WWDG downcounter clock (Hz) = PCLK1 / (4096 * Prescaler)
  35
  36     (+) WWDG timeout (ms) = (1000 * (T[5;0] + 1)) / (WWDG downcounter clock)
  37         where T[5;0] are the lowest 6 bits of downcounter.
  38
  39     (+) WWDG Counter refresh is allowed between the following limits :
  40         (++) min time (ms) = (1000 * (T[5;0] - Window)) / (WWDG downcounter clock)
  41         (++) max time (ms) = (1000 * (T[5;0] - 0x40)) / (WWDG downcounter clock)
  42
  43     (+) Min-max timeout value @80 MHz(PCLK1): ~51.2 us / ~26.22 ms
  44
  45     (+) The Early Wakeup Interrupt (EWI) can be used if specific safety
  46         operations or data logging must be performed before the actual reset is
  47         generated. When the downcounter reaches the value 0x40, an EWI interrupt
  48         is generated and the corresponding interrupt service routine (ISR) can
  49         be used to trigger specific actions (such as communications or data
  50         logging), before resetting the device.
  51         In some applications, the EWI interrupt can be used to manage a software
  52         system check and/or system recovery/graceful degradation, without
  53         generating a WWDG reset. In this case, the corresponding interrupt
  54         service routine (ISR) should reload the WWDG counter to avoid the WWDG
  55         reset, then trigger the required actions.
  56         Note:When the EWI interrupt cannot be served, e.g. due to a system lock
  57         in a higher priority task, the WWDG reset will eventually be generated.
  58
  59     (+) Debug mode : When the microcontroller enters debug mode (core halted),
  60         the WWDG counter either continues to work normally or stops, depending
  61         on DBG_WWDG_STOP configuration bit in DBG module, accessible through
  62         __HAL_DBGMCU_FREEZE_WWDG() and __HAL_DBGMCU_UNFREEZE_WWDG() macros
  63
  64                      ##### How to use this driver #####
  65   ==============================================================================
  66   [..]
  67     (+) Enable WWDG APB1 clock using __HAL_RCC_WWDG_CLK_ENABLE().
  68
  69     (+) Set the WWDG prescaler, refresh window, counter value and Early Wakeup
  70         Interrupt mode using using HAL_WWDG_Init() function.
  71         This enables WWDG peripheral and the downcounter starts downcounting
  72         from given counter value.
  73         Init function can be called again to modify all watchdog parameters,
  74         however if EWI mode has been set once, it can't be clear until next
  75         reset.
  76
  77     (+) The application program must refresh the WWDG counter at regular
  78         intervals during normal operation to prevent an MCU reset using
  79         HAL_WWDG_Refresh() function. This operation must occur only when
  80         the counter is lower than the window value already programmed.
  81
  82     (+) if Early Wakeup Interrupt mode is enable an interrupt is generated when
  83         the counter reaches 0x40. User can add his own code in weak function
  84         HAL_WWDG_EarlyWakeupCallback().
  85
  86      *** WWDG HAL driver macros list ***
  87      ==================================
  88      [..]
  89        Below the list of most used macros in WWDG HAL driver.
  90
  91       (+) __HAL_WWDG_GET_IT_SOURCE: Check the selected WWDG's interrupt source.
  92       (+) __HAL_WWDG_GET_FLAG: Get the selected WWDG's flag status.
  93       (+) __HAL_WWDG_CLEAR_FLAG: Clear the WWDG's pending flags.
  94
  95   @endverbatim
  96   ******************************************************************************
  97   * @attention
  98   *
  99   * <h2><center>&copy; COPYRIGHT(c) 2016 STMicroelectronics</center></h2>
 100   *
 101   * Redistribution and use in source and binary forms, with or without modification,
 102   * are permitted provided that the following conditions are met:
 103   *   1. Redistributions of source code must retain the above copyright notice,
 104   *      this list of conditions and the following disclaimer.
 105   *   2. Redistributions in binary form must reproduce the above copyright notice,
 106   *      this list of conditions and the following disclaimer in the documentation
 107   *      and/or other materials provided with the distribution.
 108   *   3. Neither the name of STMicroelectronics nor the names of its contributors
 109   *      may be used to endorse or promote products derived from this software
 110   *      without specific prior written permission.
 111   *
 112   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 113   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 114   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 115   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 116   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 117   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 118   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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 120   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 121   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 122   *
 123   ******************************************************************************
 124   */
 125
 126 /* Includes ------------------------------------------------------------------*/
 127 #include "stm32f7xx_hal.h"
 128
 129 /** @addtogroup STM32F7xx_HAL_Driver
 130   * @{
 131   */
 132
 133 #ifdef HAL_WWDG_MODULE_ENABLED
 134 /** @defgroup WWDG WWDG
 135   * @brief WWDG HAL module driver.
 136   * @{
 137   */
 138
 139 /* Private typedef -----------------------------------------------------------*/
 140 /* Private define ------------------------------------------------------------*/
 141 /* Private macro -------------------------------------------------------------*/
 142 /* Private variables ---------------------------------------------------------*/
 143 /* Private function prototypes -----------------------------------------------*/
 144 /* Exported functions --------------------------------------------------------*/
 145
 146 /** @defgroup WWDG_Exported_Functions WWDG Exported Functions
 147   * @{
 148   */
 149
 150 /** @defgroup WWDG_Exported_Functions_Group1 Initialization and Configuration functions
 151  *  @brief    Initialization and Configuration functions.
 152  *
 153 @verbatim
 154   ==============================================================================
 155           ##### Initialization and Configuration functions #####
 156   ==============================================================================
 157   [..]
 158     This section provides functions allowing to:
 159       (+) Initialize and start the WWDG according to the specified parameters
 160           in the WWDG_InitTypeDef of associated handle.
 161       (+) Initialize the WWDG MSP.
 162
 163 @endverbatim
 164   * @{
 165   */
 166
 167 /**
 168   * @brief  Initialize the WWDG according to the specified.
 169   *         parameters in the WWDG_InitTypeDef of  associated handle.
 170   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
 171   *                the configuration information for the specified WWDG module.
 172   * @retval HAL status
 173   */
 174 HAL_StatusTypeDef HAL_WWDG_Init(WWDG_HandleTypeDef *hwwdg)
 175 {
 176   /* Check the WWDG handle allocation */
 177   if(hwwdg == NULL)
 178   {
 179     return HAL_ERROR;
 180   }
 181
 182   /* Check the parameters */
 183   assert_param(IS_WWDG_ALL_INSTANCE(hwwdg->Instance));
 184   assert_param(IS_WWDG_PRESCALER(hwwdg->Init.Prescaler));
 185   assert_param(IS_WWDG_WINDOW(hwwdg->Init.Window));
 186   assert_param(IS_WWDG_COUNTER(hwwdg->Init.Counter));
 187   assert_param(IS_WWDG_EWI_MODE(hwwdg->Init.EWIMode));
 188
 189   /* Init the low level hardware */
 190   HAL_WWDG_MspInit(hwwdg);
 191
 192   /* Set WWDG Counter */
 193   WRITE_REG(hwwdg->Instance->CR, (WWDG_CR_WDGA | hwwdg->Init.Counter));
 194
 195   /* Set WWDG Prescaler and Window */
 196   WRITE_REG(hwwdg->Instance->CFR, (hwwdg->Init.EWIMode | hwwdg->Init.Prescaler | hwwdg->Init.Window));
 197
 198   /* Return function status */
 199   return HAL_OK;
 200 }
 201
 202
 203 /**
 204   * @brief  Initialize the WWDG MSP.
 205   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
 206   *                the configuration information for the specified WWDG module.
 207   * @note   When rewriting this function in user file, mechanism may be added
 208   *         to avoid multiple initialize when HAL_WWDG_Init function is called
 209   *         again to change parameters.
 210   * @retval None
 211   */
 212 __weak void HAL_WWDG_MspInit(WWDG_HandleTypeDef *hwwdg)
 213 {
 214   /* Prevent unused argument(s) compilation warning */
 215   UNUSED(hwwdg);
 216
 217   /* NOTE: This function should not be modified, when the callback is needed,
 218            the HAL_WWDG_MspInit could be implemented in the user file
 219    */
 220 }
 221
 222 /**
 223   * @}
 224   */
 225
 226 /** @defgroup WWDG_Exported_Functions_Group2 IO operation functions
 227  *  @brief    IO operation functions
 228  *
 229 @verbatim
 230   ==============================================================================
 231                       ##### IO operation functions #####
 232   ==============================================================================
 233   [..]
 234     This section provides functions allowing to:
 235     (+) Refresh the WWDG.
 236     (+) Handle WWDG interrupt request and associated function callback.
 237
 238 @endverbatim
 239   * @{
 240   */
 241
 242 /**
 243   * @brief  Refresh the WWDG.
 244   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
 245   *                the configuration information for the specified WWDG module.
 246   * @retval HAL status
 247   */
 248 HAL_StatusTypeDef HAL_WWDG_Refresh(WWDG_HandleTypeDef *hwwdg)
 249 {
 250   /* Write to WWDG CR the WWDG Counter value to refresh with */
 251   WRITE_REG(hwwdg->Instance->CR, (hwwdg->Init.Counter));
 252
 253   /* Return function status */
 254   return HAL_OK;
 255 }
 256
 257 /**
 258   * @brief  Handle WWDG interrupt request.
 259   * @note   The Early Wakeup Interrupt (EWI) can be used if specific safety operations
 260   *         or data logging must be performed before the actual reset is generated.
 261   *         The EWI interrupt is enabled by calling HAL_WWDG_Init function with
 262   *         EWIMode set to WWDG_EWI_ENABLE.
 263   *         When the downcounter reaches the value 0x40, and EWI interrupt is
 264   *         generated and the corresponding Interrupt Service Routine (ISR) can
 265   *         be used to trigger specific actions (such as communications or data
 266   *         logging), before resetting the device.
 267   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
 268   *                the configuration information for the specified WWDG module.
 269   * @retval None
 270   */
 271 void HAL_WWDG_IRQHandler(WWDG_HandleTypeDef *hwwdg)
 272 {
 273   /* Check if Early Wakeup Interrupt is enable */
 274   if(__HAL_WWDG_GET_IT_SOURCE(hwwdg, WWDG_IT_EWI) != RESET)
 275   {
 276     /* Check if WWDG Early Wakeup Interrupt occurred */
 277     if(__HAL_WWDG_GET_FLAG(hwwdg, WWDG_FLAG_EWIF) != RESET)
 278     {
 279       /* Clear the WWDG Early Wakeup flag */
 280       __HAL_WWDG_CLEAR_FLAG(hwwdg, WWDG_FLAG_EWIF);
 281
 282       /* Early Wakeup callback */
 283       HAL_WWDG_EarlyWakeupCallback(hwwdg);
 284     }
 285   }
 286 }
 287
 288
 289 /**
 290   * @brief  WWDG Early Wakeup callback.
 291   * @param  hwwdg  pointer to a WWDG_HandleTypeDef structure that contains
 292   *                the configuration information for the specified WWDG module.
 293   * @retval None
 294   */
 295 __weak void HAL_WWDG_EarlyWakeupCallback(WWDG_HandleTypeDef* hwwdg)
 296 {
 297   /* Prevent unused argument(s) compilation warning */
 298   UNUSED(hwwdg);
 299
 300   /* NOTE: This function should not be modified, when the callback is needed,
 301            the HAL_WWDG_EarlyWakeupCallback could be implemented in the user file
 302    */
 303 }
 304
 305 /**
 306   * @}
 307   */
 308
 309 /**
 310   * @}
 311   */
 312
 313 #endif /* HAL_WWDG_MODULE_ENABLED */
 314 /**
 315   * @}
 316   */
 317
 318 /**
 319   * @}
 320   */
 321
 322 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/