lib/main/STM32F3/Drivers/STM32F3xx_HAL_Driver/Src/stm32f3xx_hal_iwdg.c

   1 /**
   2   ******************************************************************************
   3   * @file    stm32f3xx_hal_iwdg.c
   4   * @author  MCD Application Team
   5   * @brief   IWDG HAL module driver.
   6   *          This file provides firmware functions to manage the following
   7   *          functionalities of the Independent Watchdog (IWDG) peripheral:
   8   *           + Initialization and Start functions
   9   *           + IO operation functions
  10   *
  11   @verbatim
  12   ==============================================================================
  13                     ##### IWDG Generic features #####
  14   ==============================================================================
  15   [..]
  16     (+) The IWDG can be started by either software or hardware (configurable
  17         through option byte).
  18
  19     (+) The IWDG is clocked by Low-Speed clock (LSI) and thus stays active even
  20         if the main clock fails.
  21
  22     (+) Once the IWDG is started, the LSI is forced ON and both can not be
  23         disabled. The counter starts counting down from the reset value (0xFFFU).
  24         When it reaches the end of count value (0x000U) a reset signal is
  25         generated (IWDG reset).
  26
  27     (+) Whenever the key value 0x0000 AAAA is written in the IWDG_KR register,
  28         the IWDG_RLR value is reloaded in the counter and the watchdog reset is
  29         prevented.
  30
  31     (+) The IWDG is implemented in the VDD voltage domain that is still functional
  32         in STOP and STANDBY mode (IWDG reset can wake-up from STANDBY).
  33         IWDGRST flag in RCC_CSR register can be used to inform when an IWDG
  34         reset occurs.
  35
  36     (+) Debug mode : When the microcontroller enters debug mode (core halted),
  37         the IWDG counter either continues to work normally or stops, depending
  38         on DBG_IWDG_STOP configuration bit in DBG module, accessible through
  39         __HAL_DBGMCU_FREEZE_IWDG() and __HAL_DBGMCU_UNFREEZE_IWDG() macros
  40
  41     [..] Min-max timeout value @41KHz (LSI): ~0.1ms / ~25.5s
  42          The IWDG timeout may vary due to LSI frequency dispersion. STM32F3xx
  43          devices provide the capability to measure the LSI frequency (LSI clock
  44          connected internally to TIM16 CH1 input capture). The measured value
  45          can be used to have an IWDG timeout with an acceptable accuracy.
  46
  47                      ##### How to use this driver #####
  48   ==============================================================================
  49   [..]
  50     (#) Use IWDG using HAL_IWDG_Init() function to :
  51       (++) Enable instance by writing Start keyword in IWDG_KEY register. LSI
  52            clock is forced ON and IWDG counter starts downcounting.
  53       (++) Enable write access to configuration register: IWDG_PR, IWDG_RLR &
  54            IWDG_WINR.
  55       (++) Configure the IWDG prescaler and counter reload value. This reload
  56            value will be loaded in the IWDG counter each time the watchdog is
  57            reloaded, then the IWDG will start counting down from this value.
  58       (++) wait for status flags to be reset"
  59       (++) Depending on window parameter:
  60         (+++) If Window Init parameter is same as Window register value,
  61              nothing more is done but reload counter value in order to exit
  62              function withy exact time base.
  63         (+++) Else modify Window register. This will automatically reload
  64              watchdog counter.
  65
  66     (#) Then the application program must refresh the IWDG counter at regular
  67         intervals during normal operation to prevent an MCU reset, using
  68         HAL_IWDG_Refresh() function.
  69
  70      *** IWDG HAL driver macros list ***
  71      ====================================
  72      [..]
  73        Below the list of most used macros in IWDG HAL driver:
  74       (+) __HAL_IWDG_START: Enable the IWDG peripheral
  75       (+) __HAL_IWDG_RELOAD_COUNTER: Reloads IWDG counter with value defined in
  76           the reload register
  77
  78   @endverbatim
  79   ******************************************************************************
  80   * @attention
  81   *
  82   * <h2><center>&copy; COPYRIGHT(c) 2016 STMicroelectronics</center></h2>
  83   *
  84   * Redistribution and use in source and binary forms, with or without modification,
  85   * are permitted provided that the following conditions are met:
  86   *   1. Redistributions of source code must retain the above copyright notice,
  87   *      this list of conditions and the following disclaimer.
  88   *   2. Redistributions in binary form must reproduce the above copyright notice,
  89   *      this list of conditions and the following disclaimer in the documentation
  90   *      and/or other materials provided with the distribution.
  91   *   3. Neither the name of STMicroelectronics nor the names of its contributors
  92   *      may be used to endorse or promote products derived from this software
  93   *      without specific prior written permission.
  94   *
  95   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  96   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  97   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  98   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  99   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 100   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 101   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 102   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 103   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 104   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 105   *
 106   ******************************************************************************
 107   */
 108
 109 /* Includes ------------------------------------------------------------------*/
 110 #include "stm32f3xx_hal.h"
 111
 112 /** @addtogroup STM32F3xx_HAL_Driver
 113   * @{
 114   */
 115
 116 #ifdef HAL_IWDG_MODULE_ENABLED
 117 /** @addtogroup IWDG
 118   * @brief IWDG HAL module driver.
 119   * @{
 120   */
 121
 122 /* Private typedef -----------------------------------------------------------*/
 123 /* Private define ------------------------------------------------------------*/
 124 /** @defgroup IWDG_Private_Defines IWDG Private Defines
 125   * @{
 126   */
 127 /* Status register need 5 RC LSI divided by prescaler clock to be updated. With
 128    higher prescaler (256U), and according to HSI variation, we need to wait at
 129    least 6 cycles so 48 ms. */
 130 #define HAL_IWDG_DEFAULT_TIMEOUT            48u
 131 /**
 132   * @}
 133   */
 134
 135 /* Private macro -------------------------------------------------------------*/
 136 /* Private variables ---------------------------------------------------------*/
 137 /* Private function prototypes -----------------------------------------------*/
 138 /* Exported functions --------------------------------------------------------*/
 139
 140 /** @addtogroup IWDG_Exported_Functions
 141   * @{
 142   */
 143
 144 /** @addtogroup IWDG_Exported_Functions_Group1
 145  *  @brief    Initialization and Start functions.
 146  *
 147 @verbatim
 148  ===============================================================================
 149           ##### Initialization and Start functions #####
 150  ===============================================================================
 151  [..]  This section provides functions allowing to:
 152       (+) Initialize the IWDG according to the specified parameters in the
 153           IWDG_InitTypeDef of associated handle.
 154       (+) Manage Window option.
 155       (+) Once initialization is performed in HAL_IWDG_Init function, Watchdog
 156           is reloaded in order to exit function with correct time base.
 157
 158 @endverbatim
 159   * @{
 160   */
 161
 162 /**
 163   * @brief  Initialize the IWDG according to the specified parameters in the
 164   *         IWDG_InitTypeDef and start watchdog. Before exiting function,
 165   *         watchdog is refreshed in order to have correct time base.
 166   * @param  hiwdg  pointer to a IWDG_HandleTypeDef structure that contains
 167   *                the configuration information for the specified IWDG module.
 168   * @retval HAL status
 169   */
 170 HAL_StatusTypeDef HAL_IWDG_Init(IWDG_HandleTypeDef *hiwdg)
 171 {
 172   uint32_t tickstart;
 173
 174   /* Check the IWDG handle allocation */
 175   if(hiwdg == NULL)
 176   {
 177     return HAL_ERROR;
 178   }
 179
 180   /* Check the parameters */
 181   assert_param(IS_IWDG_ALL_INSTANCE(hiwdg->Instance));
 182   assert_param(IS_IWDG_PRESCALER(hiwdg->Init.Prescaler));
 183   assert_param(IS_IWDG_RELOAD(hiwdg->Init.Reload));
 184   assert_param(IS_IWDG_WINDOW(hiwdg->Init.Window));
 185
 186   /* Enable IWDG. LSI is turned on automaticaly */
 187   __HAL_IWDG_START(hiwdg);
 188
 189   /* Enable write access to IWDG_PR, IWDG_RLR and IWDG_WINR registers by writing
 190   0x5555 in KR */
 191   IWDG_ENABLE_WRITE_ACCESS(hiwdg);
 192
 193   /* Write to IWDG registers the Prescaler & Reload values to work with */
 194   hiwdg->Instance->PR = hiwdg->Init.Prescaler;
 195   hiwdg->Instance->RLR = hiwdg->Init.Reload;
 196
 197   /* Check pending flag, if previous update not done, return timeout */
 198   tickstart = HAL_GetTick();
 199
 200    /* Wait for register to be updated */
 201   while(hiwdg->Instance->SR != RESET)
 202   {
 203     if((HAL_GetTick() - tickstart ) > HAL_IWDG_DEFAULT_TIMEOUT)
 204     {
 205       return HAL_TIMEOUT;
 206     }
 207   }
 208
 209   /* If window parameter is different than current value, modify window
 210   register */
 211   if(hiwdg->Instance->WINR != hiwdg->Init.Window)
 212   {
 213     /* Write to IWDG WINR the IWDG_Window value to compare with. In any case,
 214     even if window feature is disabled, Watchdog will be reloaded by writing
 215     windows register */
 216     hiwdg->Instance->WINR = hiwdg->Init.Window;
 217   }
 218   else
 219   {
 220     /* Reload IWDG counter with value defined in the reload register */
 221     __HAL_IWDG_RELOAD_COUNTER(hiwdg);
 222   }
 223
 224   /* Return function status */
 225   return HAL_OK;
 226 }
 227
 228 /**
 229   * @}
 230   */
 231
 232
 233 /** @addtogroup IWDG_Exported_Functions_Group2
 234  *  @brief   IO operation functions
 235  *
 236 @verbatim
 237  ===============================================================================
 238                       ##### IO operation functions #####
 239  ===============================================================================
 240  [..]  This section provides functions allowing to:
 241       (+) Refresh the IWDG.
 242
 243 @endverbatim
 244   * @{
 245   */
 246
 247
 248 /**
 249   * @brief  Refresh the IWDG.
 250   * @param  hiwdg  pointer to a IWDG_HandleTypeDef structure that contains
 251   *                the configuration information for the specified IWDG module.
 252   * @retval HAL status
 253   */
 254 HAL_StatusTypeDef HAL_IWDG_Refresh(IWDG_HandleTypeDef *hiwdg)
 255 {
 256   /* Reload IWDG counter with value defined in the reload register */
 257   __HAL_IWDG_RELOAD_COUNTER(hiwdg);
 258
 259   /* Return function status */
 260   return HAL_OK;
 261 }
 262
 263 /**
 264   * @}
 265   */
 266
 267 /**
 268   * @}
 269   */
 270
 271 #endif /* HAL_IWDG_MODULE_ENABLED */
 272 /**
 273   * @}
 274   */
 275
 276 /**
 277   * @}
 278   */
 279
 280 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/