STM32F439xx HAL User Manual
|
00001 /** 00002 ****************************************************************************** 00003 * @file stm32f4xx_hal_iwdg.c 00004 * @author MCD Application Team 00005 * @brief IWDG HAL module driver. 00006 * This file provides firmware functions to manage the following 00007 * functionalities of the Independent Watchdog (IWDG) peripheral: 00008 * + Initialization and Start functions 00009 * + IO operation functions 00010 * 00011 @verbatim 00012 ============================================================================== 00013 ##### IWDG Generic features ##### 00014 ============================================================================== 00015 [..] 00016 (+) The IWDG can be started by either software or hardware (configurable 00017 through option byte). 00018 00019 (+) The IWDG is clocked by Low-Speed clock (LSI) and thus stays active even 00020 if the main clock fails. 00021 00022 (+) Once the IWDG is started, the LSI is forced ON and both can not be 00023 disabled. The counter starts counting down from the reset value (0xFFF). 00024 When it reaches the end of count value (0x000) a reset signal is 00025 generated (IWDG reset). 00026 00027 (+) Whenever the key value 0x0000 AAAA is written in the IWDG_KR register, 00028 the IWDG_RLR value is reloaded in the counter and the watchdog reset is 00029 prevented. 00030 00031 (+) The IWDG is implemented in the VDD voltage domain that is still functional 00032 in STOP and STANDBY mode (IWDG reset can wake-up from STANDBY). 00033 IWDGRST flag in RCC_CSR register can be used to inform when an IWDG 00034 reset occurs. 00035 00036 (+) Debug mode : When the microcontroller enters debug mode (core halted), 00037 the IWDG counter either continues to work normally or stops, depending 00038 on DBG_IWDG_STOP configuration bit in DBG module, accessible through 00039 __HAL_DBGMCU_FREEZE_IWDG() and __HAL_DBGMCU_UNFREEZE_IWDG() macros 00040 00041 [..] Min-max timeout value @32KHz (LSI): ~125us / ~32.7s 00042 The IWDG timeout may vary due to LSI frequency dispersion. STM32F4xx 00043 devices provide the capability to measure the LSI frequency (LSI clock 00044 connected internally to TIM5 CH4 input capture). The measured value 00045 can be used to have an IWDG timeout with an acceptable accuracy. 00046 00047 ##### How to use this driver ##### 00048 ============================================================================== 00049 [..] 00050 (#) Use IWDG using HAL_IWDG_Init() function to : 00051 (++) Enable instance by writing Start keyword in IWDG_KEY register. LSI 00052 clock is forced ON and IWDG counter starts downcounting. 00053 (++) Enable write access to configuration register: IWDG_PR & IWDG_RLR. 00054 (++) Configure the IWDG prescaler and counter reload value. This reload 00055 value will be loaded in the IWDG counter each time the watchdog is 00056 reloaded, then the IWDG will start counting down from this value. 00057 (++) wait for status flags to be reset" 00058 00059 (#) Then the application program must refresh the IWDG counter at regular 00060 intervals during normal operation to prevent an MCU reset, using 00061 HAL_IWDG_Refresh() function. 00062 00063 *** IWDG HAL driver macros list *** 00064 ==================================== 00065 [..] 00066 Below the list of most used macros in IWDG HAL driver: 00067 (+) __HAL_IWDG_START: Enable the IWDG peripheral 00068 (+) __HAL_IWDG_RELOAD_COUNTER: Reloads IWDG counter with value defined in 00069 the reload register 00070 00071 @endverbatim 00072 ****************************************************************************** 00073 * @attention 00074 * 00075 * <h2><center>© COPYRIGHT(c) 2017 STMicroelectronics</center></h2> 00076 * 00077 * Redistribution and use in source and binary forms, with or without modification, 00078 * are permitted provided that the following conditions are met: 00079 * 1. Redistributions of source code must retain the above copyright notice, 00080 * this list of conditions and the following disclaimer. 00081 * 2. Redistributions in binary form must reproduce the above copyright notice, 00082 * this list of conditions and the following disclaimer in the documentation 00083 * and/or other materials provided with the distribution 00084 * 3. Neither the name of STMicroelectronics nor the names of its contributors 00085 * may be used to endorse or promote products derived from this software 00086 * without specific prior written permission. 00087 * 00088 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 00089 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00090 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 00091 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE 00092 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00093 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 00094 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 00095 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 00096 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 00097 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00098 * 00099 ****************************************************************************** 00100 */ 00101 00102 /* Includes ------------------------------------------------------------------*/ 00103 #include "stm32f4xx_hal.h" 00104 00105 /** @addtogroup STM32F4xx_HAL_Driver 00106 * @{ 00107 */ 00108 00109 #ifdef HAL_IWDG_MODULE_ENABLED 00110 /** @defgroup IWDG IWDG 00111 * @brief IWDG HAL module driver. 00112 * @{ 00113 */ 00114 00115 /* Private typedef -----------------------------------------------------------*/ 00116 /* Private define ------------------------------------------------------------*/ 00117 /** @defgroup IWDG_Private_Defines IWDG Private Defines 00118 * @{ 00119 */ 00120 /* Status register need 5 RC LSI divided by prescaler clock to be updated. With 00121 higher prescaler (256), and according to HSI variation, we need to wait at 00122 least 6 cycles so 48 ms. */ 00123 #define HAL_IWDG_DEFAULT_TIMEOUT 48U 00124 /** 00125 * @} 00126 */ 00127 00128 /* Private macro -------------------------------------------------------------*/ 00129 /* Private variables ---------------------------------------------------------*/ 00130 /* Private function prototypes -----------------------------------------------*/ 00131 /* Exported functions --------------------------------------------------------*/ 00132 00133 /** @addtogroup IWDG_Exported_Functions 00134 * @{ 00135 */ 00136 00137 /** @addtogroup IWDG_Exported_Functions_Group1 00138 * @brief Initialization and Start functions. 00139 * 00140 @verbatim 00141 =============================================================================== 00142 ##### Initialization and Start functions ##### 00143 =============================================================================== 00144 [..] This section provides functions allowing to: 00145 (+) Initialize the IWDG according to the specified parameters in the 00146 IWDG_InitTypeDef of associated handle. 00147 (+) Once initialization is performed in HAL_IWDG_Init function, Watchdog 00148 is reloaded in order to exit function with correct time base. 00149 00150 @endverbatim 00151 * @{ 00152 */ 00153 00154 /** 00155 * @brief Initialize the IWDG according to the specified parameters in the 00156 * IWDG_InitTypeDef and start watchdog. Before exiting function, 00157 * watchdog is refreshed in order to have correct time base. 00158 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains 00159 * the configuration information for the specified IWDG module. 00160 * @retval HAL status 00161 */ 00162 HAL_StatusTypeDef HAL_IWDG_Init(IWDG_HandleTypeDef *hiwdg) 00163 { 00164 uint32_t tickstart; 00165 00166 /* Check the IWDG handle allocation */ 00167 if(hiwdg == NULL) 00168 { 00169 return HAL_ERROR; 00170 } 00171 00172 /* Check the parameters */ 00173 assert_param(IS_IWDG_ALL_INSTANCE(hiwdg->Instance)); 00174 assert_param(IS_IWDG_PRESCALER(hiwdg->Init.Prescaler)); 00175 assert_param(IS_IWDG_RELOAD(hiwdg->Init.Reload)); 00176 00177 /* Enable IWDG. LSI is turned on automaticaly */ 00178 __HAL_IWDG_START(hiwdg); 00179 00180 /* Enable write access to IWDG_PR and IWDG_RLR registers by writing 0x5555 in KR */ 00181 IWDG_ENABLE_WRITE_ACCESS(hiwdg); 00182 00183 /* Write to IWDG registers the Prescaler & Reload values to work with */ 00184 hiwdg->Instance->PR = hiwdg->Init.Prescaler; 00185 hiwdg->Instance->RLR = hiwdg->Init.Reload; 00186 00187 /* Check pending flag, if previous update not done, return timeout */ 00188 tickstart = HAL_GetTick(); 00189 00190 /* Wait for register to be updated */ 00191 while(hiwdg->Instance->SR != RESET) 00192 { 00193 if((HAL_GetTick() - tickstart ) > HAL_IWDG_DEFAULT_TIMEOUT) 00194 { 00195 return HAL_TIMEOUT; 00196 } 00197 } 00198 00199 /* Reload IWDG counter with value defined in the reload register */ 00200 __HAL_IWDG_RELOAD_COUNTER(hiwdg); 00201 00202 /* Return function status */ 00203 return HAL_OK; 00204 } 00205 00206 /** 00207 * @} 00208 */ 00209 00210 /** @addtogroup IWDG_Exported_Functions_Group2 00211 * @brief IO operation functions 00212 * 00213 @verbatim 00214 =============================================================================== 00215 ##### IO operation functions ##### 00216 =============================================================================== 00217 [..] This section provides functions allowing to: 00218 (+) Refresh the IWDG. 00219 00220 @endverbatim 00221 * @{ 00222 */ 00223 00224 /** 00225 * @brief Refresh the IWDG. 00226 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains 00227 * the configuration information for the specified IWDG module. 00228 * @retval HAL status 00229 */ 00230 HAL_StatusTypeDef HAL_IWDG_Refresh(IWDG_HandleTypeDef *hiwdg) 00231 { 00232 /* Reload IWDG counter with value defined in the reload register */ 00233 __HAL_IWDG_RELOAD_COUNTER(hiwdg); 00234 00235 /* Return function status */ 00236 return HAL_OK; 00237 } 00238 00239 /** 00240 * @} 00241 */ 00242 00243 /** 00244 * @} 00245 */ 00246 00247 #endif /* HAL_IWDG_MODULE_ENABLED */ 00248 /** 00249 * @} 00250 */ 00251 00252 /** 00253 * @} 00254 */ 00255 00256 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/