STM32F103xB HAL User Manual
stm32f1xx_hal_pwr.c
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00001 /**
00002   ******************************************************************************
00003   * @file    stm32f1xx_hal_pwr.c
00004   * @author  MCD Application Team
00005   * @brief   PWR HAL module driver.
00006   *
00007   *          This file provides firmware functions to manage the following
00008   *          functionalities of the Power Controller (PWR) peripheral:
00009   *           + Initialization/de-initialization functions
00010   *           + Peripheral Control functions 
00011   *
00012   ******************************************************************************
00013   * @attention
00014   *
00015   * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
00016   * All rights reserved.</center></h2>
00017   *
00018   * This software component is licensed by ST under BSD 3-Clause license,
00019   * the "License"; You may not use this file except in compliance with the
00020   * License. You may obtain a copy of the License at:
00021   *                        opensource.org/licenses/BSD-3-Clause
00022   *
00023   ******************************************************************************
00024   */
00025 
00026 /* Includes ------------------------------------------------------------------*/
00027 #include "stm32f1xx_hal.h"
00028 
00029 /** @addtogroup STM32F1xx_HAL_Driver
00030   * @{
00031   */
00032 
00033 /** @defgroup PWR PWR
00034   * @brief    PWR HAL module driver
00035   * @{
00036   */
00037 
00038 #ifdef HAL_PWR_MODULE_ENABLED
00039 
00040 /* Private typedef -----------------------------------------------------------*/
00041 /* Private define ------------------------------------------------------------*/
00042 
00043 /** @defgroup PWR_Private_Constants PWR Private Constants
00044   * @{
00045   */
00046   
00047 /** @defgroup PWR_PVD_Mode_Mask PWR PVD Mode Mask
00048   * @{
00049   */ 
00050 #define PVD_MODE_IT               0x00010000U
00051 #define PVD_MODE_EVT              0x00020000U
00052 #define PVD_RISING_EDGE           0x00000001U
00053 #define PVD_FALLING_EDGE          0x00000002U
00054 /**
00055   * @}
00056   */
00057 
00058 
00059 /** @defgroup PWR_register_alias_address PWR Register alias address
00060   * @{
00061   */ 
00062 /* ------------- PWR registers bit address in the alias region ---------------*/
00063 #define PWR_OFFSET               (PWR_BASE - PERIPH_BASE)
00064 #define PWR_CR_OFFSET            0x00U
00065 #define PWR_CSR_OFFSET           0x04U
00066 #define PWR_CR_OFFSET_BB         (PWR_OFFSET + PWR_CR_OFFSET)
00067 #define PWR_CSR_OFFSET_BB        (PWR_OFFSET + PWR_CSR_OFFSET)
00068 /**
00069   * @}
00070   */
00071    
00072 /** @defgroup PWR_CR_register_alias PWR CR Register alias address
00073   * @{
00074   */  
00075 /* --- CR Register ---*/
00076 /* Alias word address of LPSDSR bit */
00077 #define LPSDSR_BIT_NUMBER        PWR_CR_LPDS_Pos
00078 #define CR_LPSDSR_BB             ((uint32_t)(PERIPH_BB_BASE + (PWR_CR_OFFSET_BB * 32U) + (LPSDSR_BIT_NUMBER * 4U)))
00079 
00080 /* Alias word address of DBP bit */
00081 #define DBP_BIT_NUMBER            PWR_CR_DBP_Pos
00082 #define CR_DBP_BB                ((uint32_t)(PERIPH_BB_BASE + (PWR_CR_OFFSET_BB * 32U) + (DBP_BIT_NUMBER * 4U)))
00083 
00084 /* Alias word address of PVDE bit */
00085 #define PVDE_BIT_NUMBER           PWR_CR_PVDE_Pos
00086 #define CR_PVDE_BB               ((uint32_t)(PERIPH_BB_BASE + (PWR_CR_OFFSET_BB * 32U) + (PVDE_BIT_NUMBER * 4U)))
00087 
00088 /**
00089   * @}
00090   */
00091 
00092 /** @defgroup PWR_CSR_register_alias PWR CSR Register alias address
00093   * @{
00094   */
00095 
00096 /* --- CSR Register ---*/
00097 /* Alias word address of EWUP1 bit */
00098 #define CSR_EWUP_BB(VAL)         ((uint32_t)(PERIPH_BB_BASE + (PWR_CSR_OFFSET_BB * 32U) + (POSITION_VAL(VAL) * 4U)))
00099 /**
00100   * @}
00101   */
00102   
00103 /**
00104   * @}
00105   */
00106 
00107 /* Private variables ---------------------------------------------------------*/
00108 /* Private function prototypes -----------------------------------------------*/
00109 /** @defgroup PWR_Private_Functions PWR Private Functions
00110  * brief   WFE cortex command overloaded for HAL_PWR_EnterSTOPMode usage only (see Workaround section)
00111  * @{
00112  */
00113 static void PWR_OverloadWfe(void);
00114 
00115 /* Private functions ---------------------------------------------------------*/
00116 __NOINLINE
00117 static void PWR_OverloadWfe(void)
00118 {
00119   __asm volatile( "wfe" );
00120   __asm volatile( "nop" );
00121 }
00122 
00123 /**
00124   * @}
00125   */
00126 
00127 
00128 /** @defgroup PWR_Exported_Functions PWR Exported Functions
00129   * @{
00130   */
00131 
00132 /** @defgroup PWR_Exported_Functions_Group1 Initialization and de-initialization functions 
00133   *  @brief   Initialization and de-initialization functions
00134   *
00135 @verbatim
00136  ===============================================================================
00137               ##### Initialization and de-initialization functions #####
00138  ===============================================================================
00139     [..]
00140       After reset, the backup domain (RTC registers, RTC backup data
00141       registers) is protected against possible unwanted
00142       write accesses.
00143       To enable access to the RTC Domain and RTC registers, proceed as follows:
00144         (+) Enable the Power Controller (PWR) APB1 interface clock using the
00145             __HAL_RCC_PWR_CLK_ENABLE() macro.
00146         (+) Enable access to RTC domain using the HAL_PWR_EnableBkUpAccess() function.
00147 
00148 @endverbatim
00149   * @{
00150   */
00151 
00152 /**
00153   * @brief  Deinitializes the PWR peripheral registers to their default reset values.  
00154   * @retval None
00155   */
00156 void HAL_PWR_DeInit(void)
00157 {
00158   __HAL_RCC_PWR_FORCE_RESET();
00159   __HAL_RCC_PWR_RELEASE_RESET();
00160 }
00161 
00162 /**
00163   * @brief  Enables access to the backup domain (RTC registers, RTC
00164   *         backup data registers ).
00165   * @note   If the HSE divided by 128 is used as the RTC clock, the
00166   *         Backup Domain Access should be kept enabled.
00167   * @retval None
00168   */
00169 void HAL_PWR_EnableBkUpAccess(void)
00170 {
00171   /* Enable access to RTC and backup registers */
00172   *(__IO uint32_t *) CR_DBP_BB = (uint32_t)ENABLE;
00173 }
00174 
00175 /**
00176   * @brief  Disables access to the backup domain (RTC registers, RTC
00177   *         backup data registers).
00178   * @note   If the HSE divided by 128 is used as the RTC clock, the
00179   *         Backup Domain Access should be kept enabled.
00180   * @retval None
00181   */
00182 void HAL_PWR_DisableBkUpAccess(void)
00183 {
00184   /* Disable access to RTC and backup registers */
00185   *(__IO uint32_t *) CR_DBP_BB = (uint32_t)DISABLE;
00186 }
00187 
00188 /**
00189   * @}
00190   */
00191 
00192 /** @defgroup PWR_Exported_Functions_Group2 Peripheral Control functions 
00193   * @brief    Low Power modes configuration functions
00194   *
00195 @verbatim
00196  ===============================================================================
00197                  ##### Peripheral Control functions #####
00198  ===============================================================================
00199      
00200     *** PVD configuration ***
00201     =========================
00202     [..]
00203       (+) The PVD is used to monitor the VDD power supply by comparing it to a
00204           threshold selected by the PVD Level (PLS[2:0] bits in the PWR_CR).
00205 
00206       (+) A PVDO flag is available to indicate if VDD/VDDA is higher or lower
00207           than the PVD threshold. This event is internally connected to the EXTI
00208           line16 and can generate an interrupt if enabled. This is done through
00209           __HAL_PVD_EXTI_ENABLE_IT() macro.
00210       (+) The PVD is stopped in Standby mode.
00211 
00212     *** WakeUp pin configuration ***
00213     ================================
00214     [..]
00215       (+) WakeUp pin is used to wake up the system from Standby mode. This pin is
00216           forced in input pull-down configuration and is active on rising edges.
00217       (+) There is one WakeUp pin:
00218           WakeUp Pin 1 on PA.00.
00219 
00220     [..]
00221 
00222     *** Low Power modes configuration ***
00223     =====================================
00224      [..]
00225       The device features 3 low-power modes:
00226       (+) Sleep mode: CPU clock off, all peripherals including Cortex-M3 core peripherals like 
00227                       NVIC, SysTick, etc. are kept running
00228       (+) Stop mode: All clocks are stopped
00229       (+) Standby mode: 1.8V domain powered off
00230   
00231   
00232    *** Sleep mode ***
00233    ==================
00234     [..]
00235       (+) Entry:
00236           The Sleep mode is entered by using the HAL_PWR_EnterSLEEPMode(PWR_MAINREGULATOR_ON, PWR_SLEEPENTRY_WFx)
00237               functions with
00238           (++) PWR_SLEEPENTRY_WFI: enter SLEEP mode with WFI instruction
00239           (++) PWR_SLEEPENTRY_WFE: enter SLEEP mode with WFE instruction
00240      
00241       (+) Exit:
00242         (++) WFI entry mode, Any peripheral interrupt acknowledged by the nested vectored interrupt
00243              controller (NVIC) can wake up the device from Sleep mode.
00244         (++) WFE entry mode, Any wakeup event can wake up the device from Sleep mode.
00245            (+++) Any peripheral interrupt w/o NVIC configuration & SEVONPEND bit set in the Cortex (HAL_PWR_EnableSEVOnPend)
00246            (+++) Any EXTI Line (Internal or External) configured in Event mode
00247 
00248    *** Stop mode ***
00249    =================
00250     [..]
00251       The Stop mode is based on the Cortex-M3 deepsleep mode combined with peripheral
00252       clock gating. The voltage regulator can be configured either in normal or low-power mode.
00253       In Stop mode, all clocks in the 1.8 V domain are stopped, the PLL, the HSI and the HSE RC 
00254       oscillators are disabled. SRAM and register contents are preserved.
00255       In Stop mode, all I/O pins keep the same state as in Run mode.
00256 
00257       (+) Entry:
00258            The Stop mode is entered using the HAL_PWR_EnterSTOPMode(PWR_REGULATOR_VALUE, PWR_SLEEPENTRY_WFx )
00259              function with:
00260           (++) PWR_REGULATOR_VALUE= PWR_MAINREGULATOR_ON: Main regulator ON.
00261           (++) PWR_REGULATOR_VALUE= PWR_LOWPOWERREGULATOR_ON: Low Power regulator ON.
00262           (++) PWR_SLEEPENTRY_WFx= PWR_SLEEPENTRY_WFI: enter STOP mode with WFI instruction
00263           (++) PWR_SLEEPENTRY_WFx= PWR_SLEEPENTRY_WFE: enter STOP mode with WFE instruction
00264       (+) Exit:
00265           (++) WFI entry mode, Any EXTI Line (Internal or External) configured in Interrupt mode with NVIC configured
00266           (++) WFE entry mode, Any EXTI Line (Internal or External) configured in Event mode.
00267 
00268    *** Standby mode ***
00269    ====================
00270      [..]
00271       The Standby mode allows to achieve the lowest power consumption. It is based on the
00272       Cortex-M3 deepsleep mode, with the voltage regulator disabled. The 1.8 V domain is 
00273       consequently powered off. The PLL, the HSI oscillator and the HSE oscillator are also 
00274       switched off. SRAM and register contents are lost except for registers in the Backup domain 
00275       and Standby circuitry
00276       
00277       (+) Entry:
00278         (++) The Standby mode is entered using the HAL_PWR_EnterSTANDBYMode() function.
00279       (+) Exit:
00280         (++) WKUP pin rising edge, RTC alarm event rising edge, external Reset in 
00281              NRSTpin, IWDG Reset
00282 
00283    *** Auto-wakeup (AWU) from low-power mode ***
00284        =============================================
00285        [..]
00286         
00287        (+) The MCU can be woken up from low-power mode by an RTC Alarm event, 
00288            without depending on an external interrupt (Auto-wakeup mode).
00289    
00290        (+) RTC auto-wakeup (AWU) from the Stop and Standby modes
00291 
00292            (++) To wake up from the Stop mode with an RTC alarm event, it is necessary to 
00293                 configure the RTC to generate the RTC alarm using the HAL_RTC_SetAlarm_IT() function.
00294 
00295    *** PWR Workarounds linked to Silicon Limitation ***
00296        ====================================================
00297        [..]
00298        Below the list of all silicon limitations known on STM32F1xx prouct.
00299 
00300        (#)Workarounds Implemented inside PWR HAL Driver
00301           (##)Debugging Stop mode with WFE entry - overloaded the WFE by an internal function    
00302         
00303 @endverbatim
00304   * @{
00305   */
00306 
00307 /**
00308   * @brief  Configures the voltage threshold detected by the Power Voltage Detector(PVD).
00309   * @param  sConfigPVD: pointer to an PWR_PVDTypeDef structure that contains the configuration
00310   *         information for the PVD.
00311   * @note   Refer to the electrical characteristics of your device datasheet for
00312   *         more details about the voltage threshold corresponding to each
00313   *         detection level.
00314   * @retval None
00315   */
00316 void HAL_PWR_ConfigPVD(PWR_PVDTypeDef *sConfigPVD)
00317 {
00318   /* Check the parameters */
00319   assert_param(IS_PWR_PVD_LEVEL(sConfigPVD->PVDLevel));
00320   assert_param(IS_PWR_PVD_MODE(sConfigPVD->Mode));
00321 
00322   /* Set PLS[7:5] bits according to PVDLevel value */
00323   MODIFY_REG(PWR->CR, PWR_CR_PLS, sConfigPVD->PVDLevel);
00324   
00325   /* Clear any previous config. Keep it clear if no event or IT mode is selected */
00326   __HAL_PWR_PVD_EXTI_DISABLE_EVENT();
00327   __HAL_PWR_PVD_EXTI_DISABLE_IT();
00328   __HAL_PWR_PVD_EXTI_DISABLE_FALLING_EDGE(); 
00329   __HAL_PWR_PVD_EXTI_DISABLE_RISING_EDGE();
00330 
00331   /* Configure interrupt mode */
00332   if((sConfigPVD->Mode & PVD_MODE_IT) == PVD_MODE_IT)
00333   {
00334     __HAL_PWR_PVD_EXTI_ENABLE_IT();
00335   }
00336   
00337   /* Configure event mode */
00338   if((sConfigPVD->Mode & PVD_MODE_EVT) == PVD_MODE_EVT)
00339   {
00340     __HAL_PWR_PVD_EXTI_ENABLE_EVENT();
00341   }
00342   
00343   /* Configure the edge */
00344   if((sConfigPVD->Mode & PVD_RISING_EDGE) == PVD_RISING_EDGE)
00345   {
00346     __HAL_PWR_PVD_EXTI_ENABLE_RISING_EDGE();
00347   }
00348   
00349   if((sConfigPVD->Mode & PVD_FALLING_EDGE) == PVD_FALLING_EDGE)
00350   {
00351     __HAL_PWR_PVD_EXTI_ENABLE_FALLING_EDGE();
00352   }
00353 }
00354 
00355 /**
00356   * @brief  Enables the Power Voltage Detector(PVD).
00357   * @retval None
00358   */
00359 void HAL_PWR_EnablePVD(void)
00360 {
00361   /* Enable the power voltage detector */
00362   *(__IO uint32_t *) CR_PVDE_BB = (uint32_t)ENABLE;
00363 }
00364 
00365 /**
00366   * @brief  Disables the Power Voltage Detector(PVD).
00367   * @retval None
00368   */
00369 void HAL_PWR_DisablePVD(void)
00370 {
00371   /* Disable the power voltage detector */
00372   *(__IO uint32_t *) CR_PVDE_BB = (uint32_t)DISABLE;
00373 }
00374 
00375 /**
00376   * @brief Enables the WakeUp PINx functionality.
00377   * @param WakeUpPinx: Specifies the Power Wake-Up pin to enable.
00378   *        This parameter can be one of the following values:
00379   *           @arg PWR_WAKEUP_PIN1
00380   * @retval None
00381   */
00382 void HAL_PWR_EnableWakeUpPin(uint32_t WakeUpPinx)
00383 {
00384   /* Check the parameter */
00385   assert_param(IS_PWR_WAKEUP_PIN(WakeUpPinx));
00386   /* Enable the EWUPx pin */
00387   *(__IO uint32_t *) CSR_EWUP_BB(WakeUpPinx) = (uint32_t)ENABLE;
00388 }
00389 
00390 /**
00391   * @brief Disables the WakeUp PINx functionality.
00392   * @param WakeUpPinx: Specifies the Power Wake-Up pin to disable.
00393   *        This parameter can be one of the following values:
00394   *           @arg PWR_WAKEUP_PIN1
00395   * @retval None
00396   */
00397 void HAL_PWR_DisableWakeUpPin(uint32_t WakeUpPinx)
00398 {
00399   /* Check the parameter */
00400   assert_param(IS_PWR_WAKEUP_PIN(WakeUpPinx));
00401   /* Disable the EWUPx pin */
00402   *(__IO uint32_t *) CSR_EWUP_BB(WakeUpPinx) = (uint32_t)DISABLE;
00403 }
00404 
00405 /**
00406   * @brief Enters Sleep mode.
00407   * @note  In Sleep mode, all I/O pins keep the same state as in Run mode.
00408   * @param Regulator: Regulator state as no effect in SLEEP mode -  allows to support portability from legacy software
00409   * @param SLEEPEntry: Specifies if SLEEP mode is entered with WFI or WFE instruction.
00410   *           When WFI entry is used, tick interrupt have to be disabled if not desired as 
00411   *           the interrupt wake up source.
00412   *           This parameter can be one of the following values:
00413   *            @arg PWR_SLEEPENTRY_WFI: enter SLEEP mode with WFI instruction
00414   *            @arg PWR_SLEEPENTRY_WFE: enter SLEEP mode with WFE instruction
00415   * @retval None
00416   */
00417 void HAL_PWR_EnterSLEEPMode(uint32_t Regulator, uint8_t SLEEPEntry)
00418 {
00419   /* Check the parameters */
00420   /* No check on Regulator because parameter not used in SLEEP mode */
00421   /* Prevent unused argument(s) compilation warning */
00422   UNUSED(Regulator);
00423 
00424   assert_param(IS_PWR_SLEEP_ENTRY(SLEEPEntry));
00425 
00426   /* Clear SLEEPDEEP bit of Cortex System Control Register */
00427   CLEAR_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SLEEPDEEP_Msk));
00428 
00429   /* Select SLEEP mode entry -------------------------------------------------*/
00430   if(SLEEPEntry == PWR_SLEEPENTRY_WFI)
00431   {
00432     /* Request Wait For Interrupt */
00433     __WFI();
00434   }
00435   else
00436   {
00437     /* Request Wait For Event */
00438     __SEV();
00439     __WFE();
00440     __WFE();
00441   }
00442 }
00443 
00444 /**
00445   * @brief Enters Stop mode. 
00446   * @note  In Stop mode, all I/O pins keep the same state as in Run mode.
00447   * @note  When exiting Stop mode by using an interrupt or a wakeup event,
00448   *        HSI RC oscillator is selected as system clock.
00449   * @note  When the voltage regulator operates in low power mode, an additional
00450   *         startup delay is incurred when waking up from Stop mode. 
00451   *         By keeping the internal regulator ON during Stop mode, the consumption
00452   *         is higher although the startup time is reduced.    
00453   * @param Regulator: Specifies the regulator state in Stop mode.
00454   *          This parameter can be one of the following values:
00455   *            @arg PWR_MAINREGULATOR_ON: Stop mode with regulator ON
00456   *            @arg PWR_LOWPOWERREGULATOR_ON: Stop mode with low power regulator ON
00457   * @param STOPEntry: Specifies if Stop mode in entered with WFI or WFE instruction.
00458   *          This parameter can be one of the following values:
00459   *            @arg PWR_STOPENTRY_WFI: Enter Stop mode with WFI instruction
00460   *            @arg PWR_STOPENTRY_WFE: Enter Stop mode with WFE instruction   
00461   * @retval None
00462   */
00463 void HAL_PWR_EnterSTOPMode(uint32_t Regulator, uint8_t STOPEntry)
00464 {
00465   /* Check the parameters */
00466   assert_param(IS_PWR_REGULATOR(Regulator));
00467   assert_param(IS_PWR_STOP_ENTRY(STOPEntry));
00468 
00469   /* Clear PDDS bit in PWR register to specify entering in STOP mode when CPU enter in Deepsleep */ 
00470   CLEAR_BIT(PWR->CR,  PWR_CR_PDDS);
00471 
00472   /* Select the voltage regulator mode by setting LPDS bit in PWR register according to Regulator parameter value */
00473   MODIFY_REG(PWR->CR, PWR_CR_LPDS, Regulator);
00474 
00475   /* Set SLEEPDEEP bit of Cortex System Control Register */
00476   SET_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SLEEPDEEP_Msk));
00477 
00478   /* Select Stop mode entry --------------------------------------------------*/
00479   if(STOPEntry == PWR_STOPENTRY_WFI)
00480   {
00481     /* Request Wait For Interrupt */
00482     __WFI();
00483   }
00484   else
00485   {
00486     /* Request Wait For Event */
00487     __SEV();
00488     PWR_OverloadWfe(); /* WFE redefine locally */
00489     PWR_OverloadWfe(); /* WFE redefine locally */
00490   }
00491   /* Reset SLEEPDEEP bit of Cortex System Control Register */
00492   CLEAR_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SLEEPDEEP_Msk));
00493 }
00494 
00495 /**
00496   * @brief Enters Standby mode.
00497   * @note  In Standby mode, all I/O pins are high impedance except for:
00498   *          - Reset pad (still available) 
00499   *          - TAMPER pin if configured for tamper or calibration out.
00500   *          - WKUP pin (PA0) if enabled.
00501   * @retval None
00502   */
00503 void HAL_PWR_EnterSTANDBYMode(void)
00504 {
00505   /* Select Standby mode */
00506   SET_BIT(PWR->CR, PWR_CR_PDDS);
00507 
00508   /* Set SLEEPDEEP bit of Cortex System Control Register */
00509   SET_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SLEEPDEEP_Msk));
00510 
00511   /* This option is used to ensure that store operations are completed */
00512 #if defined ( __CC_ARM)
00513   __force_stores();
00514 #endif
00515   /* Request Wait For Interrupt */
00516   __WFI();
00517 }
00518 
00519 
00520 /**
00521   * @brief Indicates Sleep-On-Exit when returning from Handler mode to Thread mode. 
00522   * @note Set SLEEPONEXIT bit of SCR register. When this bit is set, the processor 
00523   *       re-enters SLEEP mode when an interruption handling is over.
00524   *       Setting this bit is useful when the processor is expected to run only on
00525   *       interruptions handling.         
00526   * @retval None
00527   */
00528 void HAL_PWR_EnableSleepOnExit(void)
00529 {
00530   /* Set SLEEPONEXIT bit of Cortex System Control Register */
00531   SET_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SLEEPONEXIT_Msk));
00532 }
00533 
00534 
00535 /**
00536   * @brief Disables Sleep-On-Exit feature when returning from Handler mode to Thread mode. 
00537   * @note Clears SLEEPONEXIT bit of SCR register. When this bit is set, the processor 
00538   *       re-enters SLEEP mode when an interruption handling is over.          
00539   * @retval None
00540   */
00541 void HAL_PWR_DisableSleepOnExit(void)
00542 {
00543   /* Clear SLEEPONEXIT bit of Cortex System Control Register */
00544   CLEAR_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SLEEPONEXIT_Msk));
00545 }
00546 
00547 
00548 /**
00549   * @brief Enables CORTEX M3 SEVONPEND bit. 
00550   * @note Sets SEVONPEND bit of SCR register. When this bit is set, this causes 
00551   *       WFE to wake up when an interrupt moves from inactive to pended.
00552   * @retval None
00553   */
00554 void HAL_PWR_EnableSEVOnPend(void)
00555 {
00556   /* Set SEVONPEND bit of Cortex System Control Register */
00557   SET_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SEVONPEND_Msk));
00558 }
00559 
00560 
00561 /**
00562   * @brief Disables CORTEX M3 SEVONPEND bit. 
00563   * @note Clears SEVONPEND bit of SCR register. When this bit is set, this causes 
00564   *       WFE to wake up when an interrupt moves from inactive to pended.         
00565   * @retval None
00566   */
00567 void HAL_PWR_DisableSEVOnPend(void)
00568 {
00569   /* Clear SEVONPEND bit of Cortex System Control Register */
00570   CLEAR_BIT(SCB->SCR, ((uint32_t)SCB_SCR_SEVONPEND_Msk));
00571 }
00572 
00573 
00574 
00575 /**
00576   * @brief  This function handles the PWR PVD interrupt request.
00577   * @note   This API should be called under the PVD_IRQHandler().
00578   * @retval None
00579   */
00580 void HAL_PWR_PVD_IRQHandler(void)
00581 {
00582   /* Check PWR exti flag */
00583   if(__HAL_PWR_PVD_EXTI_GET_FLAG() != RESET)
00584   {
00585     /* PWR PVD interrupt user callback */
00586     HAL_PWR_PVDCallback();
00587 
00588     /* Clear PWR Exti pending bit */
00589     __HAL_PWR_PVD_EXTI_CLEAR_FLAG();
00590   }
00591 }
00592 
00593 /**
00594   * @brief  PWR PVD interrupt callback
00595   * @retval None
00596   */
00597 __weak void HAL_PWR_PVDCallback(void)
00598 {
00599   /* NOTE : This function Should not be modified, when the callback is needed,
00600             the HAL_PWR_PVDCallback could be implemented in the user file
00601    */ 
00602 }
00603 
00604 /**
00605   * @}
00606   */
00607 
00608 /**
00609   * @}
00610   */
00611 
00612 #endif /* HAL_PWR_MODULE_ENABLED */
00613 /**
00614   * @}
00615   */
00616 
00617 /**
00618   * @}
00619   */
00620 
00621 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/