stm32u5xx_hal_timebase_rtc_alarm_template.c

/**
  ******************************************************************************
  * @file    stm32u5xx_hal_timebase_rtc_alarm_template.c
  * @author  MCD Application Team
  * @brief   HAL time base based on the hardware RTC_ALARM Template.
  *
  *          This file overrides the native HAL time base functions (defined as weak)
  *          to use the RTC ALARM for time base generation:
  *           + Initializes the RTC peripheral to increment the seconds registers each 1ms
  *           + The alarm is configured to assert an interrupt when the RTC reaches 1ms
  *           + HAL_IncTick is called at each Alarm event
  *           + HSE (default), LSE or LSI can be selected as RTC clock source
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2021 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
 @verbatim
  ==============================================================================
                        ##### How to use this driver #####
  ==============================================================================
    [..]
    This file must be copied to the application folder and modified as follows:
    (#) Rename it to 'stm32u5xx_hal_timebase_rtc_alarm.c'
    (#) Add this file and the RTC HAL drivers to your project and uncomment
       HAL_RTC_MODULE_ENABLED define in stm32u5xx_hal_conf.h

    [..]
    (@) HAL RTC alarm and HAL RTC wakeup drivers can not be used with low power modes:
        The wake up capability of the RTC may be intrusive in case of prior low power mode
        configuration requiring different wake up sources.
        Application/Example behavior is no more guaranteed
    (@) The stm32u5xx_hal_timebase_tim use is recommended for the Applications/Examples
          requiring low power modes

  @endverbatim
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "stm32u5xx_hal.h"
/** @addtogroup STM32U5xx_HAL_Driver
  * @{
  */

/** @defgroup HAL_TimeBase_RTC_Alarm_Template  HAL TimeBase RTC Alarm Template
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/

/* Uncomment the line below to select the appropriate RTC Clock source for your application:
  + RTC_CLOCK_SOURCE_HSE: can be selected for applications requiring timing precision.
  + RTC_CLOCK_SOURCE_LSE: can be selected for applications with low constraint on timing
                          precision.
  + RTC_CLOCK_SOURCE_LSI: can be selected for applications with low constraint on timing
                          precision.
  */
/* #define RTC_CLOCK_SOURCE_HSE */
/* #define RTC_CLOCK_SOURCE_LSE */
#define RTC_CLOCK_SOURCE_LSI

/* The time base should be 1ms
   Time base = ((RTC_ASYNCH_PREDIV + 1) * (RTC_SYNCH_PREDIV + 1)) / RTC_CLOCK
*/
#if defined (RTC_CLOCK_SOURCE_HSE)
#define RTC_ASYNCH_PREDIV      99U
#define RTC_SYNCH_PREDIV        4U
#elif defined (RTC_CLOCK_SOURCE_LSE)
#define RTC_ASYNCH_PREDIV       0U
#define RTC_SYNCH_PREDIV       32U
#elif defined (RTC_CLOCK_SOURCE_LSI)
#define RTC_ASYNCH_PREDIV       0U
#define RTC_SYNCH_PREDIV       31U
#else
#error Please select the RTC Clock source
#endif /* RTC_CLOCK_SOURCE_LSE */

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
static RTC_HandleTypeDef        hRTC_Handle;

/* Private function prototypes -----------------------------------------------*/
void RTC_IRQHandler(void);
#if (USE_HAL_RTC_REGISTER_CALLBACKS == 1U)
void TimeBase_RTC_AlarmAEventCallback(RTC_HandleTypeDef *hrtc);
#endif /* USE_HAL_RTC_REGISTER_CALLBACKS */
/* Private functions ---------------------------------------------------------*/

/**
  * @brief  This function configures the RTC_ALARMA as a time base source.
  *         The time source is configured to have 1ms time base with a dedicated
  *         Tick interrupt priority.
  * @note   This function is called  automatically at the beginning of program after
  *         reset by HAL_Init() or at any time when clock is configured, by HAL_RCC_ClockConfig().
  * @param  TickPriority Tick interrupt priority.
  * @retval HAL status
  */
HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
{
  HAL_StatusTypeDef  Status;

  RCC_OscInitTypeDef        RCC_OscInitStruct;
  RCC_PeriphCLKInitTypeDef  PeriphClkInitStruct;

  /* Disable bkup domain protection */
  __HAL_RCC_PWR_CLK_ENABLE();
  HAL_PWR_EnableBkUpAccess();

  /* Force and Release the Backup domain reset */
  __HAL_RCC_BACKUPRESET_FORCE();
  __HAL_RCC_BACKUPRESET_RELEASE();

  /* Enable RTC Clock */
  __HAL_RCC_RTC_ENABLE();
  __HAL_RCC_RTCAPB_CLK_ENABLE();

#if defined (RTC_CLOCK_SOURCE_LSE)
  /* Configure LSE as RTC clock source */
  RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_LSE;
  RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_NONE;
  RCC_OscInitStruct.LSEState            = RCC_LSE_ON_RTC_ONLY;
  PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
#elif defined (RTC_CLOCK_SOURCE_LSI)
  /* Configure LSI as RTC clock source */
  RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_LSI;
  RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_NONE;
  RCC_OscInitStruct.LSIDiv              = RCC_LSI_DIV1;
  RCC_OscInitStruct.LSIState            = RCC_LSI_ON;
  PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSI;
#elif defined (RTC_CLOCK_SOURCE_HSE)
  /* Configure HSE as RTC clock source */
  RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_NONE;
  RCC_OscInitStruct.HSEState            = RCC_HSE_ON;
  PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV32;
#else
#error Please select the RTC Clock source
#endif /* RTC_CLOCK_SOURCE_LSE */

  Status = HAL_RCC_OscConfig(&RCC_OscInitStruct);

  if (Status == HAL_OK)
  {
    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC;
    Status = HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct);
  }

  if (Status == HAL_OK)
  {
    hRTC_Handle.Instance = RTC;
    hRTC_Handle.Init.HourFormat     = RTC_HOURFORMAT_24;
    hRTC_Handle.Init.AsynchPrediv   = RTC_ASYNCH_PREDIV;
    hRTC_Handle.Init.SynchPrediv    = RTC_SYNCH_PREDIV;
    hRTC_Handle.Init.OutPut         = RTC_OUTPUT_DISABLE;
    hRTC_Handle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
    hRTC_Handle.Init.OutPutType     = RTC_OUTPUT_TYPE_OPENDRAIN;
    hRTC_Handle.Init.BinMode        = RTC_BINARY_NONE;

    Status = HAL_RTC_Init(&hRTC_Handle);

#if (USE_HAL_RTC_REGISTER_CALLBACKS == 1U)
    HAL_RTC_RegisterCallback(&hRTC_Handle, HAL_RTC_ALARM_A_EVENT_CB_ID, TimeBase_RTC_AlarmAEventCallback);
#endif /* USE_HAL_RTC_REGISTER_CALLBACKS */
  }

  if (Status == HAL_OK)
  {
    /* RTC variables */
    RTC_AlarmTypeDef RTC_AlarmStructure;

    /* RTC Alarm Generation */
    RTC_AlarmStructure.Alarm                = RTC_ALARM_A;
    RTC_AlarmStructure.AlarmDateWeekDay     = RTC_WEEKDAY_MONDAY;
    RTC_AlarmStructure.AlarmDateWeekDaySel  = RTC_ALARMDATEWEEKDAYSEL_DATE;
    /* Mask all and keep only subsecond, to have one match in each time base 1ms(uwTickFreq) */
    RTC_AlarmStructure.AlarmMask            = RTC_ALARMMASK_ALL;
    RTC_AlarmStructure.AlarmSubSecondMask   = RTC_ALARMSUBSECONDMASK_NONE;
    RTC_AlarmStructure.AlarmTime.TimeFormat = RTC_HOURFORMAT_24;
    RTC_AlarmStructure.AlarmTime.Hours      = 0;
    RTC_AlarmStructure.AlarmTime.Minutes    = 0;
    RTC_AlarmStructure.AlarmTime.Seconds    = 0;
    RTC_AlarmStructure.AlarmTime.SubSeconds = 0;

    /* Set the specified RTC Alarm with Interrupt */
    Status = HAL_RTC_SetAlarm_IT(&hRTC_Handle, &RTC_AlarmStructure, RTC_FORMAT_BCD);
  }

  if (TickPriority < (1UL << __NVIC_PRIO_BITS))
  {
    /* Enable the RTC global Interrupt */
    HAL_NVIC_SetPriority(RTC_IRQn, TickPriority, 0);
    uwTickPrio = TickPriority;
  }
  else
  {
    Status = HAL_ERROR;
  }

  HAL_NVIC_EnableIRQ(RTC_IRQn);

  return Status;
}

/**
  * @brief  Suspend Tick increment.
  * @note   Disable the tick increment by disabling RTC ALARM interrupt.
  * @retval None
  */
void HAL_SuspendTick(void)
{
  /* Disable the write protection for RTC registers */
  __HAL_RTC_WRITEPROTECTION_DISABLE(&hRTC_Handle);
  /* Disable RTC ALARM update Interrupt */
  __HAL_RTC_ALARM_DISABLE_IT(&hRTC_Handle, RTC_IT_ALRA);
  /* Enable the write protection for RTC registers */
  __HAL_RTC_WRITEPROTECTION_ENABLE(&hRTC_Handle);
}

/**
  * @brief  Resume Tick increment.
  * @note   Enable the tick increment by Enabling RTC ALARM interrupt.
  * @retval None
  */
void HAL_ResumeTick(void)
{
  /* Disable the write protection for RTC registers */
  __HAL_RTC_WRITEPROTECTION_DISABLE(&hRTC_Handle);
  /* Enable RTC ALARM Update interrupt */
  __HAL_RTC_ALARM_ENABLE_IT(&hRTC_Handle, RTC_IT_ALRA);
  /* Enable the write protection for RTC registers */
  __HAL_RTC_WRITEPROTECTION_ENABLE(&hRTC_Handle);
}

/**
  * @brief  ALARM A Event Callback in non blocking mode
  * @note   This function is called  when RTC_ALARM interrupt took place, inside
  * RTC_ALARM_IRQHandler(). It makes a direct call to HAL_IncTick() to increment
  * a global variable "uwTick" used as application time base.
  * @param  hrtc RTC handle
  * @retval None
  */
#if (USE_HAL_RTC_REGISTER_CALLBACKS == 1U)
void TimeBase_RTC_AlarmAEventCallback(RTC_HandleTypeDef *hrtc)
#else
void HAL_RTC_AlarmAEventCallback(RTC_HandleTypeDef *hrtc)
#endif /* USE_HAL_RTC_REGISTER_CALLBACKS */
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(hrtc);

  HAL_IncTick();
}

/**
  * @brief  This function handles RTC ALARM interrupt request.
  * @retval None
  */
void RTC_IRQHandler(void)
{
  HAL_RTC_AlarmIRQHandler(&hRTC_Handle);
}

/**
  * @}
  */

/**
  * @}
  */