1 /**
2 ******************************************************************************
3 * @file stm32f2xx_hal_pwr_ex.c
4 * @author MCD Application Team
5 * @brief Extended PWR HAL module driver.
6 * This file provides firmware functions to manage the following
7 * functionalities of PWR extension peripheral:
8 * + Peripheral Extended features functions
9 *
10 ******************************************************************************
11 * @attention
12 *
13 * Copyright (c) 2017 STMicroelectronics.
14 * All rights reserved.
15 *
16 * This software is licensed under terms that can be found in the LICENSE file
17 * in the root directory of this software component.
18 * If no LICENSE file comes with this software, it is provided AS-IS.
19 *
20 ******************************************************************************
21 */
22
23 /* Includes ------------------------------------------------------------------*/
24 #include "stm32f2xx_hal.h"
25
26 /** @addtogroup STM32F2xx_HAL_Driver
27 * @{
28 */
29
30 /** @defgroup PWREx PWREx
31 * @brief PWR HAL module driver
32 * @{
33 */
34
35 #ifdef HAL_PWR_MODULE_ENABLED
36
37 /* Private typedef -----------------------------------------------------------*/
38 /* Private define ------------------------------------------------------------*/
39 /** @addtogroup PWREx_Private_Constants
40 * @{
41 */
42 #define PWR_BKPREG_TIMEOUT_VALUE 1000U
43 /**
44 * @}
45 */
46
47
48 /* Private macro -------------------------------------------------------------*/
49 /* Private variables ---------------------------------------------------------*/
50 /* Private function prototypes -----------------------------------------------*/
51 /* Private functions ---------------------------------------------------------*/
52 /** @defgroup PWREx_Exported_Functions PWR Exported Functions
53 * @{
54 */
55
56 /** @defgroup PWREx_Exported_Functions_Group1 Peripheral Extended features functions
57 * @brief Peripheral Extended features functions
58 *
59 @verbatim
60
61 ===============================================================================
62 ##### Peripheral extended features functions #####
63 ===============================================================================
64
65 *** Main and Backup Regulators configuration ***
66 ================================================
67 [..]
68 (+) The backup domain includes 4 Kbytes of backup SRAM accessible only from
69 the CPU, and address in 32-bit, 16-bit or 8-bit mode. Its content is
70 retained even in Standby or VBAT mode when the low power backup regulator
71 is enabled. It can be considered as an internal EEPROM when VBAT is
72 always present. You can use the HAL_PWREx_EnableBkUpReg() function to
73 enable the low power backup regulator.
74
75 (+) When the backup domain is supplied by VDD (analog switch connected to VDD)
76 the backup SRAM is powered from VDD which replaces the VBAT power supply to
77 save battery life.
78
79 (+) The backup SRAM is not mass erased by a tamper event. It is read
80 protected to prevent confidential data, such as cryptographic private
81 key, from being accessed. The backup SRAM can be erased only through
82 the Flash interface when a protection level change from level 1 to
83 level 0 is requested.
84 -@- Refer to the description of Read protection (RDP) in the Flash
85 programming manual.
86
87 Refer to the product datasheets for more details.
88
89 *** FLASH Power Down configuration ****
90 =======================================
91 [..]
92 (+) By setting the FPDS bit in the PWR_CR register by using the
93 HAL_PWREx_EnableFlashPowerDown() function, the Flash memory also enters power
94 down mode when the device enters Stop mode. When the Flash memory
95 is in power down mode, an additional startup delay is incurred when
96 waking up from Stop mode.
97
98 @endverbatim
99 * @{
100 */
101
102 /**
103 * @brief Enables the Backup Regulator.
104 * @retval HAL status
105 */
HAL_PWREx_EnableBkUpReg(void)106 HAL_StatusTypeDef HAL_PWREx_EnableBkUpReg(void)
107 {
108 uint32_t tickstart = 0U;
109
110 *(__IO uint32_t *) CSR_BRE_BB = (uint32_t)ENABLE;
111
112 /* Get tick */
113 tickstart = HAL_GetTick();
114
115 /* Wait till Backup regulator ready flag is set */
116 while(__HAL_PWR_GET_FLAG(PWR_FLAG_BRR) == RESET)
117 {
118 if((HAL_GetTick() - tickstart ) > PWR_BKPREG_TIMEOUT_VALUE)
119 {
120 return HAL_TIMEOUT;
121 }
122 }
123 return HAL_OK;
124 }
125
126 /**
127 * @brief Disables the Backup Regulator.
128 * @retval HAL status
129 */
HAL_PWREx_DisableBkUpReg(void)130 HAL_StatusTypeDef HAL_PWREx_DisableBkUpReg(void)
131 {
132 uint32_t tickstart = 0U;
133
134 *(__IO uint32_t *) CSR_BRE_BB = (uint32_t)DISABLE;
135
136 /* Get tick */
137 tickstart = HAL_GetTick();
138
139 /* Wait till Backup regulator ready flag is set */
140 while(__HAL_PWR_GET_FLAG(PWR_FLAG_BRR) != RESET)
141 {
142 if((HAL_GetTick() - tickstart ) > PWR_BKPREG_TIMEOUT_VALUE)
143 {
144 return HAL_TIMEOUT;
145 }
146 }
147 return HAL_OK;
148 }
149
150 /**
151 * @brief Enables the Flash Power Down in Stop mode.
152 * @retval None
153 */
HAL_PWREx_EnableFlashPowerDown(void)154 void HAL_PWREx_EnableFlashPowerDown(void)
155 {
156 *(__IO uint32_t *) CR_FPDS_BB = (uint32_t)ENABLE;
157 }
158
159 /**
160 * @brief Disables the Flash Power Down in Stop mode.
161 * @retval None
162 */
HAL_PWREx_DisableFlashPowerDown(void)163 void HAL_PWREx_DisableFlashPowerDown(void)
164 {
165 *(__IO uint32_t *) CR_FPDS_BB = (uint32_t)DISABLE;
166 }
167
168 /**
169 * @}
170 */
171
172 /**
173 * @}
174 */
175 #endif /* HAL_PWR_MODULE_ENABLED */
176 /**
177 * @}
178 */
179
180 /**
181 * @}
182 */
183
