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 * <h2><center>© Copyright (c) 2017 STMicroelectronics.
14 * All rights reserved.</center></h2>
15 *
16 * This software component is licensed by ST under BSD 3-Clause license,
17 * the "License"; You may not use this file except in compliance with the
18 * License. You may obtain a copy of the License at:
19 * opensource.org/licenses/BSD-3-Clause
20 *
21 ******************************************************************************
22 */
23
24 /* Includes ------------------------------------------------------------------*/
25 #include "stm32f2xx_hal.h"
26
27 /** @addtogroup STM32F2xx_HAL_Driver
28 * @{
29 */
30
31 /** @defgroup PWREx PWREx
32 * @brief PWR HAL module driver
33 * @{
34 */
35
36 #ifdef HAL_PWR_MODULE_ENABLED
37
38 /* Private typedef -----------------------------------------------------------*/
39 /* Private define ------------------------------------------------------------*/
40 /** @addtogroup PWREx_Private_Constants
41 * @{
42 */
43 #define PWR_BKPREG_TIMEOUT_VALUE 1000U
44 /**
45 * @}
46 */
47
48
49 /* Private macro -------------------------------------------------------------*/
50 /* Private variables ---------------------------------------------------------*/
51 /* Private function prototypes -----------------------------------------------*/
52 /* Private functions ---------------------------------------------------------*/
53 /** @defgroup PWREx_Exported_Functions PWR Exported Functions
54 * @{
55 */
56
57 /** @defgroup PWREx_Exported_Functions_Group1 Peripheral Extended features functions
58 * @brief Peripheral Extended features functions
59 *
60 @verbatim
61
62 ===============================================================================
63 ##### Peripheral extended features functions #####
64 ===============================================================================
65
66 *** Main and Backup Regulators configuration ***
67 ================================================
68 [..]
69 (+) The backup domain includes 4 Kbytes of backup SRAM accessible only from
70 the CPU, and address in 32-bit, 16-bit or 8-bit mode. Its content is
71 retained even in Standby or VBAT mode when the low power backup regulator
72 is enabled. It can be considered as an internal EEPROM when VBAT is
73 always present. You can use the HAL_PWREx_EnableBkUpReg() function to
74 enable the low power backup regulator.
75
76 (+) When the backup domain is supplied by VDD (analog switch connected to VDD)
77 the backup SRAM is powered from VDD which replaces the VBAT power supply to
78 save battery life.
79
80 (+) The backup SRAM is not mass erased by a tamper event. It is read
81 protected to prevent confidential data, such as cryptographic private
82 key, from being accessed. The backup SRAM can be erased only through
83 the Flash interface when a protection level change from level 1 to
84 level 0 is requested.
85 -@- Refer to the description of Read protection (RDP) in the Flash
86 programming manual.
87
88 Refer to the product datasheets for more details.
89
90 *** FLASH Power Down configuration ****
91 =======================================
92 [..]
93 (+) By setting the FPDS bit in the PWR_CR register by using the
94 HAL_PWREx_EnableFlashPowerDown() function, the Flash memory also enters power
95 down mode when the device enters Stop mode. When the Flash memory
96 is in power down mode, an additional startup delay is incurred when
97 waking up from Stop mode.
98
99 @endverbatim
100 * @{
101 */
102
103 /**
104 * @brief Enables the Backup Regulator.
105 * @retval HAL status
106 */
HAL_PWREx_EnableBkUpReg(void)107 HAL_StatusTypeDef HAL_PWREx_EnableBkUpReg(void)
108 {
109 uint32_t tickstart = 0U;
110
111 *(__IO uint32_t *) CSR_BRE_BB = (uint32_t)ENABLE;
112
113 /* Get tick */
114 tickstart = HAL_GetTick();
115
116 /* Wait till Backup regulator ready flag is set */
117 while(__HAL_PWR_GET_FLAG(PWR_FLAG_BRR) == RESET)
118 {
119 if((HAL_GetTick() - tickstart ) > PWR_BKPREG_TIMEOUT_VALUE)
120 {
121 return HAL_TIMEOUT;
122 }
123 }
124 return HAL_OK;
125 }
126
127 /**
128 * @brief Disables the Backup Regulator.
129 * @retval HAL status
130 */
HAL_PWREx_DisableBkUpReg(void)131 HAL_StatusTypeDef HAL_PWREx_DisableBkUpReg(void)
132 {
133 uint32_t tickstart = 0U;
134
135 *(__IO uint32_t *) CSR_BRE_BB = (uint32_t)DISABLE;
136
137 /* Get tick */
138 tickstart = HAL_GetTick();
139
140 /* Wait till Backup regulator ready flag is set */
141 while(__HAL_PWR_GET_FLAG(PWR_FLAG_BRR) != RESET)
142 {
143 if((HAL_GetTick() - tickstart ) > PWR_BKPREG_TIMEOUT_VALUE)
144 {
145 return HAL_TIMEOUT;
146 }
147 }
148 return HAL_OK;
149 }
150
151 /**
152 * @brief Enables the Flash Power Down in Stop mode.
153 * @retval None
154 */
HAL_PWREx_EnableFlashPowerDown(void)155 void HAL_PWREx_EnableFlashPowerDown(void)
156 {
157 *(__IO uint32_t *) CR_FPDS_BB = (uint32_t)ENABLE;
158 }
159
160 /**
161 * @brief Disables the Flash Power Down in Stop mode.
162 * @retval None
163 */
HAL_PWREx_DisableFlashPowerDown(void)164 void HAL_PWREx_DisableFlashPowerDown(void)
165 {
166 *(__IO uint32_t *) CR_FPDS_BB = (uint32_t)DISABLE;
167 }
168
169 /**
170 * @}
171 */
172
173 /**
174 * @}
175 */
176 #endif /* HAL_PWR_MODULE_ENABLED */
177 /**
178 * @}
179 */
180
181 /**
182 * @}
183 */
184
185 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
186
