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comparison Common/Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_iwdg.c @ 160:e3ca52b8e7fa

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Merge with FlipDisplay
author heinrichsweikamp
date Thu, 07 Mar 2019 15:06:43 +0100
parents c78bcbd5deda
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80:cc2bb7bb8456 160:e3ca52b8e7fa
1 /**
2 ******************************************************************************
3 * @file stm32f4xx_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 (0xFFF).
24 When it reaches the end of count value (0x000) 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 @32KHz (LSI): ~125us / ~32.7s
42 The IWDG timeout may vary due to LSI frequency dispersion. STM32F4xx
43 devices provide the capability to measure the LSI frequency (LSI clock
44 connected internally to TIM5 CH4 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 (++) Configure the IWDG prescaler and counter reload value. This reload
55 value will be loaded in the IWDG counter each time the watchdog is
56 reloaded, then the IWDG will start counting down from this value.
57 (++) wait for status flags to be reset"
58
59 (#) Then the application program must refresh the IWDG counter at regular
60 intervals during normal operation to prevent an MCU reset, using
61 HAL_IWDG_Refresh() function.
62
63 *** IWDG HAL driver macros list ***
64 ====================================
65 [..]
66 Below the list of most used macros in IWDG HAL driver:
67 (+) __HAL_IWDG_START: Enable the IWDG peripheral
68 (+) __HAL_IWDG_RELOAD_COUNTER: Reloads IWDG counter with value defined in
69 the reload register
70
71 @endverbatim
72 ******************************************************************************
73 * @attention
74 *
75 * <h2><center>&copy; COPYRIGHT(c) 2017 STMicroelectronics</center></h2>
76 *
77 * Redistribution and use in source and binary forms, with or without modification,
78 * are permitted provided that the following conditions are met:
79 * 1. Redistributions of source code must retain the above copyright notice,
80 * this list of conditions and the following disclaimer.
81 * 2. Redistributions in binary form must reproduce the above copyright notice,
82 * this list of conditions and the following disclaimer in the documentation
83 * and/or other materials provided with the distribution
84 * 3. Neither the name of STMicroelectronics nor the names of its contributors
85 * may be used to endorse or promote products derived from this software
86 * without specific prior written permission.
87 *
88 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
89 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
90 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
91 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
92 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
93 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
94 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
95 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
96 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
97 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
98 *
99 ******************************************************************************
100 */
101
102 /* Includes ------------------------------------------------------------------*/
103 #include "stm32f4xx_hal.h"
104
105 /** @addtogroup STM32F4xx_HAL_Driver
106 * @{
107 */
108
109 #ifdef HAL_IWDG_MODULE_ENABLED
110 /** @defgroup IWDG IWDG
111 * @brief IWDG HAL module driver.
112 * @{
113 */
114
115 /* Private typedef -----------------------------------------------------------*/
116 /* Private define ------------------------------------------------------------*/
117 /** @defgroup IWDG_Private_Defines IWDG Private Defines
118 * @{
119 */
120 /* Status register need 5 RC LSI divided by prescaler clock to be updated. With
121 higher prescaler (256), and according to HSI variation, we need to wait at
122 least 6 cycles so 48 ms. */
123 #define HAL_IWDG_DEFAULT_TIMEOUT 48U
124 /**
125 * @}
126 */
127
128 /* Private macro -------------------------------------------------------------*/
129 /* Private variables ---------------------------------------------------------*/
130 /* Private function prototypes -----------------------------------------------*/
131 /* Exported functions --------------------------------------------------------*/
132
133 /** @addtogroup IWDG_Exported_Functions
134 * @{
135 */
136
137 /** @addtogroup IWDG_Exported_Functions_Group1
138 * @brief Initialization and Start functions.
139 *
140 @verbatim
141 ===============================================================================
142 ##### Initialization and Start functions #####
143 ===============================================================================
144 [..] This section provides functions allowing to:
145 (+) Initialize the IWDG according to the specified parameters in the
146 IWDG_InitTypeDef of associated handle.
147 (+) Once initialization is performed in HAL_IWDG_Init function, Watchdog
148 is reloaded in order to exit function with correct time base.
149
150 @endverbatim
151 * @{
152 */
153
154 /**
155 * @brief Initialize the IWDG according to the specified parameters in the
156 * IWDG_InitTypeDef and start watchdog. Before exiting function,
157 * watchdog is refreshed in order to have correct time base.
158 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
159 * the configuration information for the specified IWDG module.
160 * @retval HAL status
161 */
162 HAL_StatusTypeDef HAL_IWDG_Init(IWDG_HandleTypeDef *hiwdg)
163 {
164 uint32_t tickstart;
165
166 /* Check the IWDG handle allocation */
167 if(hiwdg == NULL)
168 {
169 return HAL_ERROR;
170 }
171
172 /* Check the parameters */
173 assert_param(IS_IWDG_ALL_INSTANCE(hiwdg->Instance));
174 assert_param(IS_IWDG_PRESCALER(hiwdg->Init.Prescaler));
175 assert_param(IS_IWDG_RELOAD(hiwdg->Init.Reload));
176
177 /* Enable IWDG. LSI is turned on automaticaly */
178 __HAL_IWDG_START(hiwdg);
179
180 /* Enable write access to IWDG_PR and IWDG_RLR registers by writing 0x5555 in KR */
181 IWDG_ENABLE_WRITE_ACCESS(hiwdg);
182
183 /* Write to IWDG registers the Prescaler & Reload values to work with */
184 hiwdg->Instance->PR = hiwdg->Init.Prescaler;
185 hiwdg->Instance->RLR = hiwdg->Init.Reload;
186
187 /* Check pending flag, if previous update not done, return timeout */
188 tickstart = HAL_GetTick();
189
190 /* Wait for register to be updated */
191 while(hiwdg->Instance->SR != RESET)
192 {
193 if((HAL_GetTick() - tickstart ) > HAL_IWDG_DEFAULT_TIMEOUT)
194 {
195 return HAL_TIMEOUT;
196 }
197 }
198
199 /* Reload IWDG counter with value defined in the reload register */
200 __HAL_IWDG_RELOAD_COUNTER(hiwdg);
201
202 /* Return function status */
203 return HAL_OK;
204 }
205
206 /**
207 * @}
208 */
209
210 /** @addtogroup IWDG_Exported_Functions_Group2
211 * @brief IO operation functions
212 *
213 @verbatim
214 ===============================================================================
215 ##### IO operation functions #####
216 ===============================================================================
217 [..] This section provides functions allowing to:
218 (+) Refresh the IWDG.
219
220 @endverbatim
221 * @{
222 */
223
224 /**
225 * @brief Refresh the IWDG.
226 * @param hiwdg pointer to a IWDG_HandleTypeDef structure that contains
227 * the configuration information for the specified IWDG module.
228 * @retval HAL status
229 */
230 HAL_StatusTypeDef HAL_IWDG_Refresh(IWDG_HandleTypeDef *hiwdg)
231 {
232 /* Reload IWDG counter with value defined in the reload register */
233 __HAL_IWDG_RELOAD_COUNTER(hiwdg);
234
235 /* Return function status */
236 return HAL_OK;
237 }
238
239 /**
240 * @}
241 */
242
243 /**
244 * @}
245 */
246
247 #endif /* HAL_IWDG_MODULE_ENABLED */
248 /**
249 * @}
250 */
251
252 /**
253 * @}
254 */
255
256 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/