rtc.c

/**
  ******************************************************************************
  * @file    rtc.c
  * @author  Frederic Pillon
  * @brief   Provides a RTC driver
  *
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2020 STMicroelectronics</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */

#include "rtc.h"
#include "stm32yyxx_ll_rtc.h"
#include <string.h>

#if defined(STM32_CORE_VERSION) && (STM32_CORE_VERSION  > 0x01090000) &&\
    defined(HAL_RTC_MODULE_ENABLED) && !defined(HAL_RTC_MODULE_ONLY)
#if defined(STM32MP1xx)
  /**
  * Currently there is no RTC driver for STM32MP1xx. If RTC is used in the future
  * the function call HAL_RCCEx_PeriphCLKConfig() shall be done under
  * if(IS_ENGINEERING_BOOT_MODE()), since clock source selection is done by
  * First Stage Boot Loader on Cortex-A.
  */
  #error "RTC shall not be handled by Arduino in STM32MP1xx."
#endif /* STM32MP1xx */

#ifdef __cplusplus
extern "C" {
#endif

/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
static RTC_HandleTypeDef RtcHandle = {0};
static voidCallbackPtr RTCUserCallback = NULL;
static void *callbackUserData = NULL;
static voidCallbackPtr RTCSecondsIrqCallback = NULL;

static sourceClock_t clkSrc = LSI_CLOCK;
static uint8_t HSEDiv = 0;
#if !defined(STM32F1xx)
/* predividers values */
static uint8_t predivSync_bits = 0xFF;
static int8_t predivAsync = -1;
static int16_t predivSync = -1;
#else
static uint32_t prediv = RTC_AUTO_1_SECOND;
#endif /* !STM32F1xx */

static hourFormat_t initFormat = HOUR_FORMAT_12;

/* Private function prototypes -----------------------------------------------*/
static void RTC_initClock(sourceClock_t source);
#if !defined(STM32F1xx)
static void RTC_computePrediv(int8_t *asynch, int16_t *synch);
#endif /* !STM32F1xx */

static inline int _log2(int x)
{
  return (x > 0) ? (sizeof(int) * 8 - __builtin_clz(x) - 1) : 0;
}

/* Exported functions --------------------------------------------------------*/

/**
  * @brief Set RTC clock source
  * @param source: RTC clock source: LSE, LSI or HSE
  * @retval None
  */
void RTC_SetClockSource(sourceClock_t source)
{
  switch (source) {
    case LSI_CLOCK:
    case LSE_CLOCK:
    case HSE_CLOCK:
      clkSrc = source;
      break;
    default:
      clkSrc = LSI_CLOCK;
      break;
  }
}

/**
  * @brief RTC clock initialization
  *        This function configures the hardware resources used.
  * @param source: RTC clock source: LSE, LSI or HSE
  * @note  Care must be taken when HAL_RCCEx_PeriphCLKConfig() is used to select
  *        the RTC clock source; in this case the Backup domain will be reset in
  *        order to modify the RTC Clock source, as consequence RTC registers (including
  *        the backup registers) and RCC_CSR register are set to their reset values.
  * @retval None
  */
static void RTC_initClock(sourceClock_t source)
{
  RCC_PeriphCLKInitTypeDef PeriphClkInit;

  if (source == LSE_CLOCK) {
    /* Enable the clock if not already set by user */
    enableClock(LSE_CLOCK);

    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_RTC;
    PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK) {
      Error_Handler();
    }
    clkSrc = LSE_CLOCK;
  } else if (source == HSE_CLOCK) {
    /* Enable the clock if not already set by user */
    enableClock(HSE_CLOCK);

    /* HSE division factor for RTC clock must be set to ensure that
     * the clock supplied to the RTC is less than or equal to 1 MHz
     */
    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_RTC;
#if defined(STM32F1xx)
    /* HSE max is 16 MHZ divided by 128 --> 125 KHz */
    PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV128;
    HSEDiv = 128;
#elif defined(RCC_RTCCLKSOURCE_HSE_DIV32) && !defined(RCC_RTCCLKSOURCE_HSE_DIV31)
    PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV32;
    HSEDiv = 32;
#elif !defined(RCC_RTCCLKSOURCE_HSE_DIV31)
    if ((HSE_VALUE / 2) <= HSE_RTC_MAX) {
      PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV2;
      HSEDiv = 2;
    } else if ((HSE_VALUE / 4) <= HSE_RTC_MAX) {
      PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV4;
      HSEDiv = 4;
    } else if ((HSE_VALUE / 8) <= HSE_RTC_MAX) {
      PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV8;
      HSEDiv = 8;
    } else if ((HSE_VALUE / 16) <= HSE_RTC_MAX) {
      PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_HSE_DIV16;
      HSEDiv = 16;
    }
#elif defined(RCC_RTCCLKSOURCE_HSE_DIV31)
    /* Not defined for STM32F2xx */
#ifndef RCC_RTCCLKSOURCE_HSE_DIVX
#define RCC_RTCCLKSOURCE_HSE_DIVX 0x00000300U
#endif /* RCC_RTCCLKSOURCE_HSE_DIVX */
#if defined(RCC_RTCCLKSOURCE_HSE_DIV63)
#define HSEDIV_MAX 64
#define HSESHIFT 12
#else
#define HSEDIV_MAX 32
#define HSESHIFT 16
#endif
    for (HSEDiv = 2; HSEDiv < HSEDIV_MAX; HSEDiv++) {
      if ((HSE_VALUE / HSEDiv) <= HSE_RTC_MAX) {
        PeriphClkInit.RTCClockSelection = (HSEDiv << HSESHIFT) | RCC_RTCCLKSOURCE_HSE_DIVX;
        break;
      }
    }
#else
#error "Could not define RTCClockSelection"
#endif /* STM32F1xx */
    if ((HSE_VALUE / HSEDiv) > HSE_RTC_MAX) {
      Error_Handler();
    }

    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK) {
      Error_Handler();
    }
    clkSrc = HSE_CLOCK;
  } else if (source == LSI_CLOCK) {
    /* Enable the clock if not already set by user */
    enableClock(LSI_CLOCK);

    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_RTC;
    PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_LSI;
    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK) {
      Error_Handler();
    }
    clkSrc = LSI_CLOCK;
  } else {
    Error_Handler();
  }
#ifdef __HAL_RCC_RTCAPB_CLK_ENABLE
  __HAL_RCC_RTCAPB_CLK_ENABLE();
#endif
  __HAL_RCC_RTC_ENABLE();
}

#if defined(STM32F1xx)
/**
  * @brief set user asynchronous prescaler value.
  * @note  use RTC_AUTO_1_SECOND to reset value
  * @param asynch: asynchronous prescaler value in range 0 - PREDIVA_MAX
  * @retval None
  */
void RTC_setPrediv(uint32_t asynch)
{
  /* set the prescaler for a stm32F1 (value is hold by one param) */
  prediv = asynch;
  LL_RTC_SetAsynchPrescaler(RTC, asynch);
}
#else
/**
  * @brief set user (a)synchronous prescaler values.
  * @note  use -1 to reset value and use computed ones
  * @param asynch: asynchronous prescaler value in range 0 - PREDIVA_MAX
  * @param synch: synchronous prescaler value in range 0 - PREDIVS_MAX
  * @retval None
  */
void RTC_setPrediv(int8_t asynch, int16_t synch)
{
  if ((asynch >= -1) && ((uint32_t)asynch <= PREDIVA_MAX) && \
      (synch >= -1) && ((uint32_t)synch <= PREDIVS_MAX)) {
    predivAsync = asynch;
    predivSync = synch;
  } else {
    RTC_computePrediv(&predivAsync, &predivSync);
  }
  predivSync_bits = (uint8_t)_log2(predivSync) + 1;
}
#endif /* STM32F1xx */

#if defined(STM32F1xx)
/**
  * @brief get user asynchronous prescaler value for the current clock source.
  * @param asynch: pointer where return asynchronous prescaler value.
  * @retval None
  */
void RTC_getPrediv(uint32_t *asynch)
{
  /* get the prescaler for a stm32F1 (value is hold by one param) */
  prediv = LL_RTC_GetDivider(RTC);
  *asynch = prediv;
}
#else
/**
  * @brief get user (a)synchronous prescaler values if set else computed ones
  *        for the current clock source.
  * @param asynch: pointer where return asynchronous prescaler value.
  * @param synch: pointer where return synchronous prescaler value.
  * @retval None
  */
void RTC_getPrediv(int8_t *asynch, int16_t *synch)
{
  if ((predivAsync == -1) || (predivSync == -1)) {
    RTC_computePrediv(&predivAsync, &predivSync);
  }
  if ((asynch != NULL) && (synch != NULL)) {
    *asynch = predivAsync;
    *synch = predivSync;
  }
  predivSync_bits = (uint8_t)_log2(predivSync) + 1;
}
#endif /* STM32F1xx */

#if !defined(STM32F1xx)
/**
  * @brief Compute (a)synchronous prescaler
  *        RTC prescalers are compute to obtain the RTC clock to 1Hz. See AN4759.
  * @param asynch: pointer where return asynchronous prescaler value.
  * @param synch: pointer where return synchronous prescaler value.
  * @retval None
  */
static void RTC_computePrediv(int8_t *asynch, int16_t *synch)
{
  uint32_t predivS = PREDIVS_MAX + 1;
  uint32_t clk = 0;

  /* Get user predividers if manually configured */
  if ((asynch == NULL) || (synch == NULL)) {
    return;
  }

  /* Get clock frequency */
  if (clkSrc == LSE_CLOCK) {
    clk = LSE_VALUE;
  } else if (clkSrc == LSI_CLOCK) {
    clk = LSI_VALUE;
  } else if (clkSrc == HSE_CLOCK) {
    clk = HSE_VALUE / HSEDiv;
  } else {
    Error_Handler();
  }

  /* Find (a)synchronous prescalers to obtain the 1Hz calendar clock */
  for (*asynch = PREDIVA_MAX; *asynch >= 0; (*asynch)--) {
    predivS = (clk / (*asynch + 1)) - 1;

    if (((predivS + 1) * (*asynch + 1)) == clk) {
      break;
    }
  }

  /*
   * Can't find a 1Hz, so give priority to RTC power consumption
   * by choosing the higher possible value for predivA
   */
  if ((predivS > PREDIVS_MAX) || (*asynch < 0)) {
    *asynch = PREDIVA_MAX;
    predivS = (clk / (*asynch + 1)) - 1;
  }

  if (predivS > PREDIVS_MAX) {
    Error_Handler();
  }
  *synch = (int16_t)predivS;
}
#endif /* !STM32F1xx */

/**
  * @brief RTC Initialization
  *        This function configures the RTC time and calendar. By default, the
  *        RTC is set to the 1st January 2001
  *        Note: year 2000 is invalid as it is the hardware reset value and doesn't raise INITS flag
  * @param format: enable the RTC in 12 or 24 hours mode
  * @param source: RTC clock source: LSE, LSI or HSE
  * @param reset: force RTC reset, even if previously configured
  * @retval True if RTC is reinitialized, else false
  */
bool RTC_init(hourFormat_t format, sourceClock_t source, bool reset)
{
  bool reinit = false;

  initFormat = format;

  /* Init RTC clock */
  RTC_initClock(source);

  RtcHandle.Instance = RTC;

  /* Ensure backup domain is enabled before we init the RTC so we can use the backup registers for date retention on stm32f1xx boards */
  enableBackupDomain();

  if (reset) {
    resetBackupDomain();
    RTC_initClock(source);
  }

#if defined(STM32F1xx)
  uint32_t BackupDate;
  BackupDate = getBackupRegister(RTC_BKP_DATE) << 16;
  BackupDate |= getBackupRegister(RTC_BKP_DATE + 1) & 0xFFFF;
  if ((BackupDate == 0) || reset) {
    /* Let HAL calculate the prescaler */
    RtcHandle.Init.AsynchPrediv = prediv;
    RtcHandle.Init.OutPut = RTC_OUTPUTSOURCE_NONE;
    HAL_RTC_Init(&RtcHandle);
    // Default: saturday 1st of January 2001
    // Note: year 2000 is invalid as it is the hardware reset value and doesn't raise INITS flag
    RTC_SetDate(1, 1, 1, 6);
    reinit = true;
  } else {
    memcpy(&RtcHandle.DateToUpdate, &BackupDate, 4);
    /* and fill the new RTC Date value */
    RTC_SetDate(RtcHandle.DateToUpdate.Year, RtcHandle.DateToUpdate.Month,
                RtcHandle.DateToUpdate.Date, RtcHandle.DateToUpdate.WeekDay);
  }
#else

  if (!LL_RTC_IsActiveFlag_INITS(RtcHandle.Instance) || reset) {
    RtcHandle.Init.HourFormat = format == HOUR_FORMAT_12 ? RTC_HOURFORMAT_12 : RTC_HOURFORMAT_24;
    RtcHandle.Init.OutPut = RTC_OUTPUT_DISABLE;
    RtcHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
    RtcHandle.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
#if defined(RTC_OUTPUT_REMAP_NONE)
    RtcHandle.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
#endif /* RTC_OUTPUT_REMAP_NONE */

    RTC_getPrediv((int8_t *) & (RtcHandle.Init.AsynchPrediv), (int16_t *) & (RtcHandle.Init.SynchPrediv));

    HAL_RTC_Init(&RtcHandle);
    // Default: saturday 1st of January 2001
    // Note: year 2000 is invalid as it is the hardware reset value and doesn't raise INITS flag
    RTC_SetDate(1, 1, 1, 6);
    reinit = true;
  } else {
    // This initialize variables: predivAsync, redivSync and predivSync_bits
    RTC_getPrediv(NULL, NULL);
  }
#endif /* STM32F1xx */

#if defined(RTC_CR_BYPSHAD)
  /* Enable Direct Read of the calendar registers (not through Shadow) */
  HAL_RTCEx_EnableBypassShadow(&RtcHandle);
#endif

  return reinit;
}

/**
  * @brief RTC deinitialization. Stop the RTC.
  * @retval None
  */
void RTC_DeInit(void)
{
  HAL_RTC_DeInit(&RtcHandle);
  RTCUserCallback = NULL;
  callbackUserData = NULL;
  RTCSecondsIrqCallback = NULL;
}

/**
  * @brief Check if time is already set
  * @retval True if set else false
  */
bool RTC_IsConfigured(void)
{
#if defined(STM32F1xx)
  uint32_t BackupDate;
  BackupDate = getBackupRegister(RTC_BKP_DATE) << 16;
  BackupDate |= getBackupRegister(RTC_BKP_DATE + 1) & 0xFFFF;
  return (BackupDate != 0);
#else
  return LL_RTC_IsActiveFlag_INITS(RtcHandle.Instance);
#endif
}

/**
  * @brief Set RTC time
  * @param hours: 0-12 or 0-23. Depends on the format used.
  * @param minutes: 0-59
  * @param seconds: 0-59
  * @param subSeconds: 0-999
  * @param period: select HOUR_AM or HOUR_PM period in case RTC is set in 12 hours mode. Else ignored.
  * @retval None
  */
void RTC_SetTime(uint8_t hours, uint8_t minutes, uint8_t seconds, uint32_t subSeconds, hourAM_PM_t period)
{
  RTC_TimeTypeDef RTC_TimeStruct;
  UNUSED(subSeconds);
  /* Ignore time AM PM configuration if in 24 hours format */
  if (initFormat == HOUR_FORMAT_24) {
    period = HOUR_AM;
  }

  if ((((initFormat == HOUR_FORMAT_24) && IS_RTC_HOUR24(hours)) || IS_RTC_HOUR12(hours))
      && IS_RTC_MINUTES(minutes) && IS_RTC_SECONDS(seconds)) {
    RTC_TimeStruct.Hours = hours;
    RTC_TimeStruct.Minutes = minutes;
    RTC_TimeStruct.Seconds = seconds;
#if !defined(STM32F1xx)
    if (period == HOUR_PM) {
      RTC_TimeStruct.TimeFormat = RTC_HOURFORMAT12_PM;
    } else {
      RTC_TimeStruct.TimeFormat = RTC_HOURFORMAT12_AM;
    }
#if defined(RTC_SSR_SS)
    /* subSeconds is read only, so no need to set it */
    /*RTC_TimeStruct.SubSeconds = subSeconds;*/
    /*RTC_TimeStruct.SecondFraction = 0;*/
#endif /* RTC_SSR_SS */
    RTC_TimeStruct.DayLightSaving = RTC_STOREOPERATION_RESET;
    RTC_TimeStruct.StoreOperation = RTC_DAYLIGHTSAVING_NONE;
#else
    UNUSED(period);
#endif /* !STM32F1xx */

    HAL_RTC_SetTime(&RtcHandle, &RTC_TimeStruct, RTC_FORMAT_BIN);
  }
}

/**
  * @brief Get RTC time
  * @param hours: 0-12 or 0-23. Depends on the format used.
  * @param minutes: 0-59
  * @param seconds: 0-59
  * @param subSeconds: 0-999 (optional could be NULL)
  * @param period: HOUR_AM or HOUR_PM period in case RTC is set in 12 hours mode (optional could be NULL).
  * @retval None
  */
void RTC_GetTime(uint8_t *hours, uint8_t *minutes, uint8_t *seconds, uint32_t *subSeconds, hourAM_PM_t *period)
{
  RTC_TimeTypeDef RTC_TimeStruct;

  if ((hours != NULL) && (minutes != NULL) && (seconds != NULL)) {
#if defined(STM32F1xx)
    /* Store the date prior to checking the time, this may roll over to the next day as part of the time check,
       we need to the new date details in the backup registers if it changes */
    uint8_t current_date = RtcHandle.DateToUpdate.Date;
#endif

    HAL_RTC_GetTime(&RtcHandle, &RTC_TimeStruct, RTC_FORMAT_BIN);
    *hours = RTC_TimeStruct.Hours;
    *minutes = RTC_TimeStruct.Minutes;
    *seconds = RTC_TimeStruct.Seconds;
#if !defined(STM32F1xx)
    if (period != NULL) {
      if (RTC_TimeStruct.TimeFormat == RTC_HOURFORMAT12_PM) {
        *period = HOUR_PM;
      } else {
        *period = HOUR_AM;
      }
    }
#if defined(RTC_SSR_SS)
    if (subSeconds != NULL) {
      *subSeconds = ((predivSync - RTC_TimeStruct.SubSeconds) * 1000) / (predivSync + 1);
    }
#else
    UNUSED(subSeconds);
#endif /* RTC_SSR_SS */
#else
    UNUSED(period);
    UNUSED(subSeconds);

    if (current_date != RtcHandle.DateToUpdate.Date) {
      RTC_StoreDate();
    }
#endif /* !STM32F1xx */
  }
}

/**
  * @brief Set RTC calendar
  * @param year: 0-99
  * @param month: 1-12
  * @param day: 1-31
  * @param wday: 1-7
  * @retval None
  */
void RTC_SetDate(uint8_t year, uint8_t month, uint8_t day, uint8_t wday)
{
  RTC_DateTypeDef RTC_DateStruct;

  if (IS_RTC_YEAR(year) && IS_RTC_MONTH(month) && IS_RTC_DATE(day) && IS_RTC_WEEKDAY(wday)) {
    RTC_DateStruct.Year = year;
    RTC_DateStruct.Month = month;
    RTC_DateStruct.Date = day;
    RTC_DateStruct.WeekDay = wday;
    HAL_RTC_SetDate(&RtcHandle, &RTC_DateStruct, RTC_FORMAT_BIN);
#if defined(STM32F1xx)
    RTC_StoreDate();
#endif /* STM32F1xx */
  }
}

/**
  * @brief Get RTC calendar
  * @param year: 0-99
  * @param month: 1-12
  * @param day: 1-31
  * @param wday: 1-7
  * @retval None
  */
void RTC_GetDate(uint8_t *year, uint8_t *month, uint8_t *day, uint8_t *wday)
{
  RTC_DateTypeDef RTC_DateStruct;

  if ((year != NULL) && (month != NULL) && (day != NULL) && (wday != NULL)) {
    HAL_RTC_GetDate(&RtcHandle, &RTC_DateStruct, RTC_FORMAT_BIN);
    *year = RTC_DateStruct.Year;
    *month = RTC_DateStruct.Month;
    *day = RTC_DateStruct.Date;
    *wday = RTC_DateStruct.WeekDay;
#if defined(STM32F1xx)
    RTC_StoreDate();
#endif /* STM32F1xx */
  }
}

/**
  * @brief Set RTC alarm and activate it with IT mode
  * @param day: 1-31 (day of the month)
  * @param hours: 0-12 or 0-23 depends on the hours mode.
  * @param minutes: 0-59
  * @param seconds: 0-59
  * @param subSeconds: 0-999
  * @param period: HOUR_AM or HOUR_PM if in 12 hours mode else ignored.
  * @param mask: configure alarm behavior using alarmMask_t combination.
  *              See AN4579 Table 5 for possible values.
  * @retval None
  */
void RTC_StartAlarm(uint8_t day, uint8_t hours, uint8_t minutes, uint8_t seconds, uint32_t subSeconds, hourAM_PM_t period, uint8_t mask)
{
  RTC_AlarmTypeDef RTC_AlarmStructure;

  /* Ignore time AM PM configuration if in 24 hours format */
  if (initFormat == HOUR_FORMAT_24) {
    period = HOUR_AM;
  }

  if ((((initFormat == HOUR_FORMAT_24) && IS_RTC_HOUR24(hours)) || IS_RTC_HOUR12(hours))
      && IS_RTC_DATE(day) && IS_RTC_MINUTES(minutes) && IS_RTC_SECONDS(seconds)) {
    /* Set RTC_AlarmStructure with calculated values*/
    /* Use alarm A by default because it is common to all STM32 HAL */
    RTC_AlarmStructure.Alarm = RTC_ALARM_A;
    RTC_AlarmStructure.AlarmTime.Seconds = seconds;
    RTC_AlarmStructure.AlarmTime.Minutes = minutes;
    RTC_AlarmStructure.AlarmTime.Hours = hours;
#if !defined(STM32F1xx)
#if defined(RTC_SSR_SS)
    if (subSeconds < 1000) {
      RTC_AlarmStructure.AlarmSubSecondMask = predivSync_bits << RTC_ALRMASSR_MASKSS_Pos;
      RTC_AlarmStructure.AlarmTime.SubSeconds = predivSync - (subSeconds * (predivSync + 1)) / 1000;
    } else {
      RTC_AlarmStructure.AlarmSubSecondMask = RTC_ALARMSUBSECONDMASK_ALL;
    }
#else
    UNUSED(subSeconds);
#endif /* RTC_SSR_SS */
    if (period == HOUR_PM) {
      RTC_AlarmStructure.AlarmTime.TimeFormat = RTC_HOURFORMAT12_PM;
    } else {
      RTC_AlarmStructure.AlarmTime.TimeFormat = RTC_HOURFORMAT12_AM;
    }
    RTC_AlarmStructure.AlarmTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
    RTC_AlarmStructure.AlarmTime.StoreOperation = RTC_STOREOPERATION_RESET;
    RTC_AlarmStructure.AlarmDateWeekDay = day;
    RTC_AlarmStructure.AlarmDateWeekDaySel = RTC_ALARMDATEWEEKDAYSEL_DATE;
    /* configure AlarmMask (M_MSK and Y_MSK ignored) */
    if (mask == OFF_MSK) {
      RTC_AlarmStructure.AlarmMask = RTC_ALARMMASK_ALL;
    } else {
      RTC_AlarmStructure.AlarmMask = RTC_ALARMMASK_NONE;
      if (!(mask & SS_MSK)) {
        RTC_AlarmStructure.AlarmMask |= RTC_ALARMMASK_SECONDS;
      }
      if (!(mask & MM_MSK)) {
        RTC_AlarmStructure.AlarmMask |= RTC_ALARMMASK_MINUTES;
      }
      if (!(mask & HH_MSK)) {
        RTC_AlarmStructure.AlarmMask |= RTC_ALARMMASK_HOURS;
      }
      if (!(mask & D_MSK)) {
        RTC_AlarmStructure.AlarmMask |= RTC_ALARMMASK_DATEWEEKDAY;
      }
    }
#else
    UNUSED(subSeconds);
    UNUSED(period);
    UNUSED(day);
    UNUSED(mask);
#endif /* !STM32F1xx */

    /* Set RTC_Alarm */
    HAL_RTC_SetAlarm_IT(&RtcHandle, &RTC_AlarmStructure, RTC_FORMAT_BIN);
    HAL_NVIC_SetPriority(RTC_Alarm_IRQn, RTC_IRQ_PRIO, RTC_IRQ_SUBPRIO);
    HAL_NVIC_EnableIRQ(RTC_Alarm_IRQn);
  }
}

/**
  * @brief Disable RTC alarm
  * @param None
  * @retval None
  */
void RTC_StopAlarm(void)
{
  /* Clear RTC Alarm Flag */
  __HAL_RTC_ALARM_CLEAR_FLAG(&RtcHandle, RTC_FLAG_ALRAF);

  /* Disable the Alarm A interrupt */
  HAL_RTC_DeactivateAlarm(&RtcHandle, RTC_ALARM_A);
}

/**
  * @brief Check whether RTC alarm is set
  * @param None
  * @retval True if Alarm is set
  */
bool RTC_IsAlarmSet(void)
{
#if defined(STM32F1xx)
  return LL_RTC_IsEnabledIT_ALR(RtcHandle.Instance);
#else
  return LL_RTC_IsEnabledIT_ALRA(RtcHandle.Instance);
#endif
}

/**
  * @brief Get RTC alarm
  * @param day: 1-31 day of the month (optional could be NULL)
  * @param hours: 0-12 or 0-23 depends on the hours mode
  * @param minutes: 0-59
  * @param seconds: 0-59
  * @param subSeconds: 0-999 (optional could be NULL)
  * @param period: HOUR_AM or HOUR_PM (optional could be NULL)
  * @param mask: alarm behavior using alarmMask_t combination (optional could be NULL)
  *              See AN4579 Table 5 for possible values
  * @retval None
  */
void RTC_GetAlarm(uint8_t *day, uint8_t *hours, uint8_t *minutes, uint8_t *seconds, uint32_t *subSeconds, hourAM_PM_t *period, uint8_t *mask)
{
  RTC_AlarmTypeDef RTC_AlarmStructure;

  if ((hours != NULL) && (minutes != NULL) && (seconds != NULL)) {
    HAL_RTC_GetAlarm(&RtcHandle, &RTC_AlarmStructure, RTC_ALARM_A, RTC_FORMAT_BIN);

    *seconds = RTC_AlarmStructure.AlarmTime.Seconds;
    *minutes = RTC_AlarmStructure.AlarmTime.Minutes;
    *hours = RTC_AlarmStructure.AlarmTime.Hours;

#if !defined(STM32F1xx)
    if (day != NULL) {
      *day = RTC_AlarmStructure.AlarmDateWeekDay;
    }
    if (period != NULL) {
      if (RTC_AlarmStructure.AlarmTime.TimeFormat == RTC_HOURFORMAT12_PM) {
        *period = HOUR_PM;
      } else {
        *period = HOUR_AM;
      }
    }
#if defined(RTC_SSR_SS)
    if (subSeconds != NULL) {
      *subSeconds = ((predivSync - RTC_AlarmStructure.AlarmTime.SubSeconds) * 1000) / (predivSync + 1);
    }
#else
    UNUSED(subSeconds);
#endif /* RTC_SSR_SS */
    if (mask != NULL) {
      *mask = OFF_MSK;
      if (!(RTC_AlarmStructure.AlarmMask & RTC_ALARMMASK_SECONDS)) {
        *mask |= SS_MSK;
      }
      if (!(RTC_AlarmStructure.AlarmMask & RTC_ALARMMASK_MINUTES)) {
        *mask |= MM_MSK;
      }
      if (!(RTC_AlarmStructure.AlarmMask & RTC_ALARMMASK_HOURS)) {
        *mask |= HH_MSK;
      }
      if (!(RTC_AlarmStructure.AlarmMask & RTC_ALARMMASK_DATEWEEKDAY)) {
        *mask |= D_MSK;
      }
    }
#else
    UNUSED(day);
    UNUSED(period);
    UNUSED(subSeconds);
    UNUSED(mask);
#endif /* !STM32F1xx */
  }
}

/**
  * @brief Attach alarm callback.
  * @param func: pointer to the callback
  * @retval None
  */
void attachAlarmCallback(voidCallbackPtr func, void *data)
{
  RTCUserCallback = func;
  callbackUserData = data;
}

/**
  * @brief Detach alarm callback.
  * @param None
  * @retval None
  */
void detachAlarmCallback(void)
{
  RTCUserCallback = NULL;
  callbackUserData = NULL;
}

/**
  * @brief  Alarm A callback.
  * @param  hrtc RTC handle
  * @retval None
  */
void HAL_RTC_AlarmAEventCallback(RTC_HandleTypeDef *hrtc)
{
  UNUSED(hrtc);

  if (RTCUserCallback != NULL) {
    RTCUserCallback(callbackUserData);
  }
}

/**
  * @brief  RTC Alarm IRQHandler
  * @param  None
  * @retval None
  */
void RTC_Alarm_IRQHandler(void)
{
  HAL_RTC_AlarmIRQHandler(&RtcHandle);
}

#ifdef ONESECOND_IRQn
/**
  * @brief Attach Seconds interrupt callback.
  * @note  stm32F1 has a second interrupt capability
  *        other MCUs map this on their WakeUp feature
  * @param func: pointer to the callback
  * @retval None
  */
void attachSecondsIrqCallback(voidCallbackPtr func)
{
#if defined(STM32F1xx)
  /* callback called on Seconds interrupt */
  RTCSecondsIrqCallback = func;

  HAL_RTCEx_SetSecond_IT(&RtcHandle);
  __HAL_RTC_SECOND_CLEAR_FLAG(&RtcHandle, RTC_FLAG_SEC);
#else
  /* callback called on wakeUp interrupt for One-Second purpose*/
  RTCSecondsIrqCallback = func;

  /* for MCUs using the wakeup feature : irq each second */
#if defined(RTC_WUTR_WUTOCLR)
  HAL_RTCEx_SetWakeUpTimer_IT(&RtcHandle, 0, RTC_WAKEUPCLOCK_CK_SPRE_16BITS, 0);
#else
  HAL_RTCEx_SetWakeUpTimer_IT(&RtcHandle, 0, RTC_WAKEUPCLOCK_CK_SPRE_16BITS);
#endif /* RTC_WUTR_WUTOCLR */

#endif /* STM32F1xx */
  /* enable the IRQ that will trig the one-second interrupt */
  HAL_NVIC_EnableIRQ(ONESECOND_IRQn);
}

/**
  * @brief Detach Seconds interrupt callback.
  * @param None
  * @retval None
  */
void detachSecondsIrqCallback(void)
{
#if defined(STM32F1xx)
  HAL_RTCEx_DeactivateSecond(&RtcHandle);
#else
  /* for MCUs using the wakeup feature : do not deactivate the WakeUp
     as it might be used for another reason than the One-Second purpose */
  // HAL_RTCEx_DeactivateWakeUpTimer(&RtcHandle);
#endif /* STM32F1xx */
  RTCSecondsIrqCallback = NULL;
}

#if defined(STM32F1xx)
/**
  * @brief  Seconds interrupt callback.
  * @param  hrtc RTC handle
  * @retval None
  */
void HAL_RTCEx_RTCEventCallback(RTC_HandleTypeDef *hrtc)
{
  UNUSED(hrtc);

  if (RTCSecondsIrqCallback != NULL) {
    RTCSecondsIrqCallback(NULL);
  }
}

/**
  * @brief  This function handles RTC Seconds interrupt request.
  * @param  None
  * @retval None
  */
void RTC_IRQHandler(void)
{
  HAL_RTCEx_RTCIRQHandler(&RtcHandle);
}

#else
/**
  * @brief  WakeUp event mapping the Seconds interrupt callback.
  * @param  hrtc RTC handle
  * @retval None
  */
void HAL_RTCEx_WakeUpTimerEventCallback(RTC_HandleTypeDef *hrtc)
{
  UNUSED(hrtc);

  if (RTCSecondsIrqCallback != NULL) {
    RTCSecondsIrqCallback(NULL);
  }
}

/**
  * @brief  This function handles RTC Seconds through wakeup interrupt request.
  * @param  None
  * @retval None
  */
void RTC_WKUP_IRQHandler(void)
{
  HAL_RTCEx_WakeUpTimerIRQHandler(&RtcHandle);
}
#endif /* STM32F1xx */
#endif /* ONESECOND_IRQn */

#if defined(STM32F1xx)
void RTC_StoreDate(void)
{
  /* Store the date in the backup registers */
  uint32_t dateToStore;
  memcpy(&dateToStore, &RtcHandle.DateToUpdate, 4);
  setBackupRegister(RTC_BKP_DATE, dateToStore >> 16);
  setBackupRegister(RTC_BKP_DATE + 1, dateToStore & 0xffff);
}
#endif

#ifdef __cplusplus
}
#endif

#endif /* HAL_RTC_MODULE_ENABLED  && !HAL_RTC_MODULE_ONLY */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/