/*!
    \file  gd32f4xx_rtc.c
    \brief RTC driver
*/

/*
    Copyright (C) 2016 GigaDevice

    2016-08-15, V1.0.0, firmware for GD32F4xx
*/

#include "gd32f4xx_rtc.h"

/* RTC timeout value */
#define RTC_WTWF_TIMEOUT                   ((uint32_t)0x00004000U)                    /*!< wakeup timer can be write flag timeout */
#define RTC_INITM_TIMEOUT                  ((uint32_t)0x00004000U)                    /*!< initialization state flag timeout */
#define RTC_RSYNF_TIMEOUT                  ((uint32_t)0x00008000U)                    /*!< register synchronization flag timeout */
#define RTC_HRFC_TIMEOUT                   ((uint32_t)0x20000000U)                    /*!< recalibration pending flag timeout */
#define RTC_SHIFTCTL_TIMEOUT               ((uint32_t)0x00001000U)                    /*!< shift function operation pending flag timeout */
#define RTC_ALRMXWF_TIMEOUT                ((uint32_t)0x00008000U)                    /*!< alarm configuration can be write flag timeout */


/*!
    \brief      reset most of the RTC registers
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_deinit(void)
{
    ErrStatus error_status = ERROR;
    volatile uint32_t time_index = RTC_WTWF_TIMEOUT;
    uint32_t flag_status = RESET;
    /* RTC_TAMP register is not under write protection */
    RTC_TAMP = RTC_REGISTER_RESET;

    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    /* enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){
        /* reset RTC_CTL register, but RTC_CTL[2£º0] */
        RTC_CTL &= (RTC_REGISTER_RESET | RTC_CTL_WTCS);
        /* before reset RTC_TIME and RTC_DATE, BPSHAD bit in RTC_CTL should be reset as the condition.
           in order to read calendar from shadow register, not the real registers being reset */
        RTC_TIME = RTC_REGISTER_RESET;
        RTC_DATE = RTC_DATE_RESET;

        RTC_PSC = RTC_PSC_RESET;
        /* only when RTC_CTL_WTEN=0 and RTC_STAT_WTWF=1 can write RTC_CTL[2£º0] */
        /* wait until the WTWF flag to be set */
        do{
           flag_status = RTC_STAT & RTC_STAT_WTWF;
        }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));

        if ((uint32_t)RESET == flag_status){
            error_status = ERROR;
        }else{
            RTC_CTL &= RTC_REGISTER_RESET;
            RTC_WUT = RTC_WUT_RESET;
            RTC_COSC = RTC_REGISTER_RESET;
            /* to write RTC_ALRMxSS register, ALRMxEN bit in RTC_CTL register should be reset as the condition */
            RTC_ALRM0TD = RTC_REGISTER_RESET;        
            RTC_ALRM1TD = RTC_REGISTER_RESET;
            RTC_ALRM0SS = RTC_REGISTER_RESET;
            RTC_ALRM1SS = RTC_REGISTER_RESET;
            /* reset RTC_STAT register, also exit init mode.
               at the same time, RTC_STAT_SOPF bit is reset, as the condition to reset RTC_SHIFTCTL register later */
            RTC_STAT = RTC_STAT_RESET;
            /* reset RTC_SHIFTCTL and RTC_HRFC register, this can be done without the init mode */
            RTC_SHIFTCTL   = RTC_REGISTER_RESET;       
            RTC_HRFC       = RTC_REGISTER_RESET;
            error_status = rtc_register_sync_wait(); 
        }
    }

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      initialize RTC registers
    \param[in]  rtc_initpara_struct: pointer to a rtc_parameter_struct structure which contains 
                parameters for initialization of the rtc peripheral
                members of the structure and the member values are shown as below:
                  year: 0x0 - 0x99(BCD format)
                  month: RTC_JAN, RTC_FEB, RTC_MAR, RTC_APR, RTC_MAY, RTC_JUN,
                             RTC_JUL, RTC_AUG, RTC_SEP, RTC_OCT, RTC_NOV, RTC_DEC
                  date: 0x1 - 0x31(BCD format)
                  day_of_week: RTC_MONDAY, RTC_TUESDAY, RTC_WEDSDAY, RTC_THURSDAY
                                   RTC_FRIDAY, RTC_SATURDAY, RTC_SUNDAY
                  hour: 0x0 - 0x12(BCD format) or 0x0 - 0x23(BCD format) depending on the rtc_display_format chose
                  minute: 0x0 - 0x59(BCD format)
                  second: 0x0 - 0x59(BCD format)
                  factor_asyn: 0x0 - 0x7F
                  factor_syn: 0x0 - 0x7FFF
                  am_pm: RTC_AM, RTC_PM
                  display_format: RTC_24HOUR, RTC_12HOUR
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_init(rtc_parameter_struct* rtc_initpara_struct)
{
    ErrStatus error_status = ERROR;
    uint32_t reg_time = 0U, reg_date = 0U;

    reg_date = (DATE_YR(rtc_initpara_struct->year) | \
                DATE_DOW(rtc_initpara_struct->day_of_week) | \
                DATE_MON(rtc_initpara_struct->month) | \
                DATE_DAY(rtc_initpara_struct->date)); 
    
    reg_time = (rtc_initpara_struct->am_pm| \
                TIME_HR(rtc_initpara_struct->hour)  | \
                TIME_MN(rtc_initpara_struct->minute) | \
                TIME_SC(rtc_initpara_struct->second)); 
              
    /* 1st: disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    /* 2nd: enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){    
        RTC_PSC = (uint32_t)(PSC_FACTOR_A(rtc_initpara_struct->factor_asyn)| \
                             PSC_FACTOR_S(rtc_initpara_struct->factor_syn));

        RTC_TIME = (uint32_t)reg_time;
        RTC_DATE = (uint32_t)reg_date;

        RTC_CTL &= (uint32_t)(~RTC_CTL_CS);
        RTC_CTL |=  rtc_initpara_struct->display_format;
        
        /* 3rd: exit init mode */  
        rtc_init_mode_exit();
        
        /* 4th: wait the RSYNF flag to set */          
        error_status = rtc_register_sync_wait();
    }

    /* 5th:  enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      enter RTC init mode
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_init_mode_enter(void)
{
    volatile uint32_t time_index = RTC_INITM_TIMEOUT;
    uint32_t flag_status = RESET;
    ErrStatus error_status = ERROR;

    /* check whether it has been in init mode */
    if ((uint32_t)RESET == (RTC_STAT & RTC_STAT_INITF)){   
        RTC_STAT |= RTC_STAT_INITM;
        
        /* wait until the INITF flag to be set */
        do{
           flag_status = RTC_STAT & RTC_STAT_INITF;
        }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));

        if ((uint32_t)RESET != flag_status){        
            error_status = SUCCESS;
        }
    }else{
        error_status = SUCCESS;
    }
    return error_status;
}

/*!
    \brief      exit RTC init mode
    \param[in]  none
    \param[out] none
    \retval     none
*/
void rtc_init_mode_exit(void)
{
    RTC_STAT &= (uint32_t)(~RTC_STAT_INITM);
}

/*!
    \brief      wait until RTC_TIME and RTC_DATE registers are synchronized with APB clock, and the shadow 
                registers are updated
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_register_sync_wait(void)
{
    volatile uint32_t time_index = RTC_RSYNF_TIMEOUT;
    uint32_t flag_status = RESET;
    ErrStatus error_status = ERROR;

    if ((uint32_t)RESET == (RTC_CTL & RTC_CTL_BPSHAD)){
        /* disable the write protection */
        RTC_WPK = RTC_UNLOCK_KEY1;
        RTC_WPK = RTC_UNLOCK_KEY2;

        /* firstly clear RSYNF flag */
        RTC_STAT &= (uint32_t)(~RTC_STAT_RSYNF);

        /* wait until RSYNF flag to be set */
        do{
            flag_status = RTC_STAT & RTC_STAT_RSYNF;
        }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));

        if ((uint32_t)RESET != flag_status){  
            error_status = SUCCESS;
        }
        
        /* enable the write protection */
        RTC_WPK = RTC_LOCK_KEY;
    }else{ 
        error_status = SUCCESS;
    }

    return error_status;
}

/*!
    \brief      get current time and date
    \param[in]  none
    \param[out] rtc_initpara_struct: pointer to a rtc_parameter_struct structure which contains 
                parameters for initialization of the rtc peripheral
                members of the structure and the member values are shown as below:
                  year: 0x0 - 0x99(BCD format)
                  month: RTC_JAN, RTC_FEB, RTC_MAR, RTC_APR, RTC_MAY, RTC_JUN,
                             RTC_JUL, RTC_AUG, RTC_SEP, RTC_OCT, RTC_NOV, RTC_DEC
                  date: 0x1 - 0x31(BCD format)
                  day_of_week: RTC_MONDAY, RTC_TUESDAY, RTC_WEDSDAY, RTC_THURSDAY
                                   RTC_FRIDAY, RTC_SATURDAY, RTC_SUNDAY
                  hour: 0x0 - 0x12(BCD format) or 0x0 - 0x23(BCD format) depending on the rtc_display_format chose
                  minute: 0x0 - 0x59(BCD format)
                  second: 0x0 - 0x59(BCD format)
                  factor_asyn: 0x0 - 0x7F
                  factor_syn: 0x0 - 0x7FFF
                  am_pm: RTC_AM, RTC_PM
                  display_format: RTC_24HOUR, RTC_12HOUR
    \retval     none
*/
void rtc_current_time_get(rtc_parameter_struct* rtc_initpara_struct)
{
    uint32_t temp_tr = 0U, temp_dr = 0U, temp_pscr = 0U, temp_ctlr = 0U;

    temp_tr = (uint32_t)RTC_TIME;   
    temp_dr = (uint32_t)RTC_DATE;
    temp_pscr = (uint32_t)RTC_PSC;
    temp_ctlr = (uint32_t)RTC_CTL;
  
    /* get current time and construct rtc_parameter_struct structure */
    rtc_initpara_struct->year = (uint8_t)GET_DATE_YR(temp_dr);
    rtc_initpara_struct->month = (uint8_t)GET_DATE_MON(temp_dr);
    rtc_initpara_struct->date = (uint8_t)GET_DATE_DAY(temp_dr);
    rtc_initpara_struct->day_of_week = (uint8_t)GET_DATE_DOW(temp_dr);  
    rtc_initpara_struct->hour = (uint8_t)GET_TIME_HR(temp_tr);
    rtc_initpara_struct->minute = (uint8_t)GET_TIME_MN(temp_tr);
    rtc_initpara_struct->second = (uint8_t)GET_TIME_SC(temp_tr);
    rtc_initpara_struct->factor_asyn = (uint16_t)GET_PSC_FACTOR_A(temp_pscr);
    rtc_initpara_struct->factor_syn = (uint16_t)GET_PSC_FACTOR_S(temp_pscr);
    rtc_initpara_struct->am_pm = (uint32_t)(temp_pscr & RTC_TIME_PM); 
    rtc_initpara_struct->display_format = (uint32_t)(temp_ctlr & RTC_CTL_CS);
}

/*!
    \brief      get current subsecond value
    \param[in]  none
    \param[out] none
    \retval     current subsecond value
*/
uint32_t rtc_subsecond_get(void)
{
    uint32_t reg = 0U;
    /* if BPSHAD bit is reset, reading RTC_SS will lock RTC_TIME and RTC_DATE automatically */
    reg = (uint32_t)RTC_SS;
    /* read RTC_DATE to unlock the 3 shadow registers */
    (void) (RTC_DATE);

    return reg;
}

/*!
    \brief      configure RTC alarm
    \param[in]  rtc_alarm: RTC_ALARM0 or RTC_ALARM1
    \param[in]  rtc_alarm_time: pointer to a rtc_alarm_struct structure which contains 
                parameters for RTC alarm configuration
                members of the structure and the member values are shown as below:
                  alarm_mask: RTC_ALARM_NONE_MASK, RTC_ALARM_DATE_MASK, RTC_ALARM_HOUR_MASK
                                  RTC_ALARM_MINUTE_MASK, RTC_ALARM_SECOND_MASK, RTC_ALARM_ALL_MASK
                  weekday_or_date: RTC_ALARM_DATE_SELECTED, RTC_ALARM_WEEKDAY_SELECTED
                  alarm_day: 1) 0x1 - 0x31(BCD format) if RTC_ALARM_DATE_SELECTED is set
                                 2) RTC_MONDAY, RTC_TUESDAY, RTC_WEDSDAY, RTC_THURSDAY, RTC_FRIDAY,
                                    RTC_SATURDAY, RTC_SUNDAY if RTC_ALARM_WEEKDAY_SELECTED is set
                  alarm_hour: 0x0 - 0x12(BCD format) or 0x0 - 0x23(BCD format) depending on the rtc_display_format
                  alarm_minute: 0x0 - 0x59(BCD format)
                  alarm_second: 0x0 - 0x59(BCD format)
                  am_pm: RTC_AM, RTC_PM
    \param[out] none
    \retval     none
*/
void rtc_alarm_config(uint8_t rtc_alarm, rtc_alarm_struct* rtc_alarm_time)
{
    uint32_t reg_alrmtd = 0U;

    reg_alrmtd =(rtc_alarm_time->alarm_mask | \
                 rtc_alarm_time->weekday_or_date | \
                 rtc_alarm_time->am_pm | \
                 ALRMTD_DAY(rtc_alarm_time->alarm_day) | \
                 ALRMTD_HR(rtc_alarm_time->alarm_hour) | \
                 ALRMTD_MN(rtc_alarm_time->alarm_minute) | \
                 ALRMTD_SC(rtc_alarm_time->alarm_second));

    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    if(RTC_ALARM0 == rtc_alarm){
        RTC_ALRM0TD = (uint32_t)reg_alrmtd;
    
    }else{
        RTC_ALRM1TD = (uint32_t)reg_alrmtd;
    }
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      configure subsecond of RTC alarm
    \param[in]  rtc_alarm: RTC_ALARM0 or RTC_ALARM1
    \param[in]  mask_subsecond: alarm subsecond mask
      \arg        RTC_MASKSSC_0_14: mask alarm subsecond configuration
      \arg        RTC_MASKSSC_1_14: mask RTC_ALRMXSS_SSC[14:1], and RTC_ALRMXSS_SSC[0] is to be compared
      \arg        RTC_MASKSSC_2_14: mask RTC_ALRMXSS_SSC[14:2], and RTC_ALRMXSS_SSC[1:0] is to be compared
      \arg        RTC_MASKSSC_3_14: mask RTC_ALRMXSS_SSC[14:3], and RTC_ALRMXSS_SSC[2:0] is to be compared
      \arg        RTC_MASKSSC_4_14: mask RTC_ALRMXSS_SSC[14:4]], and RTC_ALRMXSS_SSC[3:0] is to be compared
      \arg        RTC_MASKSSC_5_14: mask RTC_ALRMXSS_SSC[14:5], and RTC_ALRMXSS_SSC[4:0] is to be compared
      \arg        RTC_MASKSSC_6_14: mask RTC_ALRMXSS_SSC[14:6], and RTC_ALRMXSS_SSC[5:0] is to be compared
      \arg        RTC_MASKSSC_7_14: mask RTC_ALRMXSS_SSC[14:7], and RTC_ALRMXSS_SSC[6:0] is to be compared
      \arg        RTC_MASKSSC_8_14: mask RTC_ALRMXSS_SSC[14:8], and RTC_ALRMXSS_SSC[7:0] is to be compared
      \arg        RTC_MASKSSC_9_14: mask RTC_ALRMXSS_SSC[14:9], and RTC_ALRMXSS_SSC[8:0] is to be compared
      \arg        RTC_MASKSSC_10_14: mask RTC_ALRMXSS_SSC[14:10], and RTC_ALRMXSS_SSC[9:0] is to be compared
      \arg        RTC_MASKSSC_11_14: mask RTC_ALRMXSS_SSC[14:11], and RTC_ALRMXSS_SSC[10:0] is to be compared
      \arg        RTC_MASKSSC_12_14: mask RTC_ALRMXSS_SSC[14:12], and RTC_ALRMXSS_SSC[11:0] is to be compared
      \arg        RTC_MASKSSC_13_14: mask RTC_ALRMXSS_SSC[14:13], and RTC_ALRMXSS_SSC[12:0] is to be compared
      \arg        RTC_MASKSSC_14: mask RTC_ALRMXSS_SSC[14], and RTC_ALRMXSS_SSC[13:0] is to be compared
      \arg        RTC_MASKSSC_NONE: mask none, and RTC_ALRMXSS_SSC[14:0] is to be compared
    \param[in]  subsecond: alarm subsecond value(0x000 - 0x7FFF)
    \param[out] none
    \retval     none
*/
void rtc_alarm_subsecond_config(uint8_t rtc_alarm, uint32_t mask_subsecond, uint32_t subsecond)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;  

    if(RTC_ALARM0 == rtc_alarm){
        RTC_ALRM0SS = mask_subsecond | subsecond;  
    }else{
        RTC_ALRM1SS = mask_subsecond | subsecond; 
    }
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      get RTC alarm
    \param[in]  rtc_alarm: RTC_ALARM0 or RTC_ALARM1
    \param[out] rtc_alarm_time: pointer to a rtc_alarm_struct structure which contains 
                parameters for RTC alarm configuration
                members of the structure and the member values are shown as below:
                  alarm_mask: RTC_ALARM_NONE_MASK, RTC_ALARM_DATE_MASK, RTC_ALARM_HOUR_MASK
                                  RTC_ALARM_MINUTE_MASK, RTC_ALARM_SECOND_MASK, RTC_ALARM_ALL_MASK
                  weekday_or_date: RTC_ALARM_DATE_SELECTED, RTC_ALARM_WEEKDAY_SELECTED
                  alarm_day: 1) 0x1 - 0x31(BCD format) if RTC_ALARM_DATE_SELECTED is set
                                 2) RTC_MONDAY, RTC_TUESDAY, RTC_WEDSDAY, RTC_THURSDAY, RTC_FRIDAY,
                                    RTC_SATURDAY, RTC_SUNDAY if RTC_ALARM_WEEKDAY_SELECTED is set
                  alarm_hour: 0x0 - 0x12(BCD format) or 0x0 - 0x23(BCD format) depending on the rtc_display_format
                  alarm_minute: 0x0 - 0x59(BCD format)
                  alarm_second: 0x0 - 0x59(BCD format)
                  am_pm: RTC_AM, RTC_PM
    \retval     none
*/
void rtc_alarm_get(uint8_t rtc_alarm, rtc_alarm_struct* rtc_alarm_time)
{
    uint32_t reg_alrmtd = 0U;

    /* get the value of RTC_ALRM0TD register */
    if(RTC_ALARM0 == rtc_alarm){
        reg_alrmtd = RTC_ALRM0TD;
    }else{
        reg_alrmtd = RTC_ALRM1TD;
    }
    /* get alarm parameters and construct the rtc_alarm_struct structure */
    rtc_alarm_time->alarm_mask = reg_alrmtd & RTC_ALARM_ALL_MASK; 
    rtc_alarm_time->am_pm = (uint32_t)(reg_alrmtd & RTC_ALRMXTD_PM);
    rtc_alarm_time->weekday_or_date = (uint32_t)(reg_alrmtd & RTC_ALRMXTD_DOWS);
    rtc_alarm_time->alarm_day = (uint8_t)GET_ALRMTD_DAY(reg_alrmtd);
    rtc_alarm_time->alarm_hour = (uint8_t)GET_ALRMTD_HR(reg_alrmtd);
    rtc_alarm_time->alarm_minute = (uint8_t)GET_ALRMTD_MN(reg_alrmtd);
    rtc_alarm_time->alarm_second = (uint8_t)GET_ALRMTD_SC(reg_alrmtd);  
}

/*!
    \brief      get RTC alarm subsecond
    \param[in]  rtc_alarm: RTC_ALARM0 or RTC_ALARM1
    \param[out] none
    \retval     RTC alarm subsecond value
*/
uint32_t rtc_alarm_subsecond_get(uint8_t rtc_alarm)
{
    if(RTC_ALARM0 == rtc_alarm){
        return ((uint32_t)(RTC_ALRM0SS & RTC_ALRM0SS_SSC));
    }else{
        return ((uint32_t)(RTC_ALRM1SS & RTC_ALRM1SS_SSC));
    }
}

/*!
    \brief      enable RTC alarm
    \param[in]  rtc_alarm: RTC_ALARM0 or RTC_ALARM1
    \param[out] none
    \retval     none
*/
void rtc_alarm_enable(uint8_t rtc_alarm)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    if(RTC_ALARM0 == rtc_alarm){
        RTC_CTL |= RTC_CTL_ALRM0EN;
    }else{
        RTC_CTL |= RTC_CTL_ALRM1EN;
    }
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      disable RTC alarm
    \param[in]  rtc_alarm: RTC_ALARM0 or RTC_ALARM1
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_alarm_disable(uint8_t rtc_alarm)
{
    volatile uint32_t time_index = RTC_ALRMXWF_TIMEOUT;
    ErrStatus error_status = ERROR;
    uint32_t flag_status = RESET;

    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    
    /* clear the state of alarm */
    if(RTC_ALARM0 == rtc_alarm){
        RTC_CTL &= (uint32_t)(~RTC_CTL_ALRM0EN); 
        /* wait until ALRM0WF flag to be set after the alarm is disabled */
        do{
            flag_status = RTC_STAT & RTC_STAT_ALRM0WF;
        }while((--time_index > 0U) && ((uint32_t)RESET == flag_status)); 
    }else{
        RTC_CTL &= (uint32_t)(~RTC_CTL_ALRM1EN);  
        /* wait until ALRM1WF flag to be set after the alarm is disabled */
        do{
            flag_status = RTC_STAT & RTC_STAT_ALRM1WF;
        }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));
    }
  
    if ((uint32_t)RESET != flag_status){     
        error_status = SUCCESS;
    }

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      enable RTC time-stamp
    \param[in]  edge: specify which edge to detect of time-stamp
      \arg        RTC_TIMESTAMP_RISING_EDGE: rising edge is valid event edge for timestamp event
      \arg        RTC_TIMESTAMP_FALLING_EDGE: falling edge is valid event edge for timestamp event
    \param[out] none
    \retval     none
*/
void rtc_timestamp_enable(uint32_t edge)
{
    uint32_t reg_ctl = 0U;

    /* clear the bits to be configured in RTC_CTL */
    reg_ctl = (uint32_t)(RTC_CTL & (uint32_t)(~(RTC_CTL_TSEG | RTC_CTL_TSEN)));

    /* new configuration */
    reg_ctl |= (uint32_t)(edge | RTC_CTL_TSEN);
   
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    RTC_CTL = (uint32_t)reg_ctl;

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      disable RTC time-stamp
    \param[in]  none
    \param[out] none
    \retval     none
*/
void rtc_timestamp_disable(void)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    
    /* clear the TSEN bit */
    RTC_CTL &= (uint32_t)(~ RTC_CTL_TSEN);

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      get RTC timestamp time and date
    \param[in]  none
    \param[out] rtc_timestamp: pointer to a rtc_timestamp_struct structure which contains 
                parameters for RTC time-stamp configuration
                members of the structure and the member values are shown as below:
                  timestamp_month: RTC_JAN, RTC_FEB, RTC_MAR, RTC_APR, RTC_MAY, RTC_JUN,
                                       RTC_JUL, RTC_AUG, RTC_SEP, RTC_OCT, RTC_NOV, RTC_DEC
                  timestamp_date: 0x1 - 0x31(BCD format)
                  timestamp_day: RTC_MONDAY, RTC_TUESDAY, RTC_WEDSDAY, RTC_THURSDAY, RTC_FRIDAY,
                                     RTC_SATURDAY, RTC_SUNDAY if RTC_ALARM_WEEKDAY_SELECTED is set
                  timestamp_hour: 0x0 - 0x12(BCD format) or 0x0 - 0x23(BCD format) depending on the rtc_display_format
                  timestamp_minute: 0x0 - 0x59(BCD format)
                  timestamp_second: 0x0 - 0x59(BCD format)
                  am_pm: RTC_AM, RTC_PM
    \retval     none
*/
void rtc_timestamp_get(rtc_timestamp_struct* rtc_timestamp)
{
    uint32_t temp_tts = 0U, temp_dts = 0U;

    /* get the value of time_stamp registers */
    temp_tts = (uint32_t)RTC_TTS;
    temp_dts = (uint32_t)RTC_DTS;
  
    /* get timestamp time and construct the rtc_timestamp_struct structure */
    rtc_timestamp->am_pm = (uint32_t)(temp_tts & RTC_TTS_PM);
    rtc_timestamp->timestamp_month = (uint8_t)GET_DTS_MON(temp_dts);
    rtc_timestamp->timestamp_date = (uint8_t)GET_DTS_DAY(temp_dts);
    rtc_timestamp->timestamp_day = (uint8_t)GET_DTS_DOW(temp_dts);
    rtc_timestamp->timestamp_hour = (uint8_t)GET_TTS_HR(temp_tts);
    rtc_timestamp->timestamp_minute = (uint8_t)GET_TTS_MN(temp_tts);
    rtc_timestamp->timestamp_second = (uint8_t)GET_TTS_SC(temp_tts);
}

/*!
    \brief      get RTC time-stamp subsecond
    \param[in]  none
    \param[out] none
    \retval     RTC time-stamp subsecond value
*/
uint32_t rtc_timestamp_subsecond_get(void)
{
    return ((uint32_t)RTC_SSTS);
}

/*!
    \brief      RTC time-stamp mapping 
    \param[in]  rtc_af:
      \arg        RTC_AF0_TIMESTAMP: RTC_AF0 use for timestamp
      \arg        RTC_AF1_TIMESTAMP: RTC_AF1 use for timestamp
    \param[out] none
    \retval     none
*/
void rtc_timestamp_pin_map(uint32_t rtc_af)
{
    RTC_TAMP &= ~RTC_TAMP_TSSEL;
    RTC_TAMP |= rtc_af;
}

/*!
    \brief      enable RTC tamper
    \param[in]  rtc_tamper: pointer to a rtc_tamper_struct structure which contains 
                parameters for RTC tamper configuration
                members of the structure and the member values are shown as below:
                  tamper_source: RTC_TAMPER0, RTC_TAMPER1
                  tamper_trigger: RTC_TAMPER_TRIGGER_EDGE_RISING, RTC_TAMPER_TRIGGER_EDGE_FALLING
                                      RTC_TAMPER_TRIGGER_LEVEL_LOW, RTC_TAMPER_TRIGGER_LEVEL_HIGH
                  tamper_filter: RTC_FLT_EDGE, RTC_FLT_2S, RTC_FLT_4S, RTC_FLT_8S
                  tamper_sample_frequency: RTC_FREQ_DIV32768, RTC_FREQ_DIV16384, RTC_FREQ_DIV8192,
                                               RTC_FREQ_DIV4096, RTC_FREQ_DIV2048, RTC_FREQ_DIV1024,
                                               RTC_FREQ_DIV512, RTC_FREQ_DIV256
                  tamper_precharge_enable: DISABLE, ENABLE
                  tamper_precharge_time: RTC_PRCH_1C, RTC_PRCH_2C, RTC_PRCH_4C, RTC_PRCH_8C
                  tamper_with_timestamp: DISABLE, ENABLE
    \param[out] none
    \retval     none
*/
void rtc_tamper_enable(rtc_tamper_struct* rtc_tamper)
{
    /* disable tamper */
    RTC_TAMP &= (uint32_t)~(rtc_tamper->tamper_source); 

    /* tamper filter must be used when the tamper source is voltage level detection */
    RTC_TAMP &= (uint32_t)~RTC_TAMP_FLT;
    
    /* the tamper source is voltage level detection */
    if((uint32_t)(rtc_tamper->tamper_filter) != RTC_FLT_EDGE ){ 
        RTC_TAMP &= (uint32_t)~(RTC_TAMP_DISPU | RTC_TAMP_PRCH | RTC_TAMP_FREQ | RTC_TAMP_FLT);

        /* check if the tamper pin need precharge, if need, then configure the precharge time */
        if(DISABLE == rtc_tamper->tamper_precharge_enable){
            RTC_TAMP |=  (uint32_t)RTC_TAMP_DISPU;    
        }else{
            RTC_TAMP |= (uint32_t)(rtc_tamper->tamper_precharge_time);
        }

        RTC_TAMP |= (uint32_t)(rtc_tamper->tamper_sample_frequency);
        RTC_TAMP |= (uint32_t)(rtc_tamper->tamper_filter);
    }
    
    RTC_TAMP &= (uint32_t)~RTC_TAMP_TPTS;  
    
    if(DISABLE != rtc_tamper->tamper_with_timestamp){           
        /* the tamper event also cause a time-stamp event */
        RTC_TAMP |= (uint32_t)RTC_TAMP_TPTS;
    } 
    
    /* configure the tamper trigger */
    RTC_TAMP &= ((uint32_t)~((rtc_tamper->tamper_source) << RTC_TAMPER_TRIGGER_POS));    
    if(RTC_TAMPER_TRIGGER_EDGE_RISING != rtc_tamper->tamper_trigger){
        RTC_TAMP |= (uint32_t)((rtc_tamper->tamper_source)<< RTC_TAMPER_TRIGGER_POS);  
    }    
    /* enable tamper */
    RTC_TAMP |=  (uint32_t)(rtc_tamper->tamper_source); 
}

/*!
    \brief      disable RTC tamper
    \param[in]  source: specify which tamper source to be disabled
      \arg        RTC_TAMPER0
      \arg        RTC_TAMPER1
    \param[out] none
    \retval     none
*/
void rtc_tamper_disable(uint32_t source)
{
    /* disable tamper */
    RTC_TAMP &= (uint32_t)~source; 

}

/*!
    \brief      RTC tamper0 mapping 
    \param[in]  rtc_af:
      \arg        RTC_AF0_TAMPER0: RTC_AF0 use for tamper0
      \arg        RTC_AF1_TAMPER0: RTC_AF1 use for tamper0
    \param[out] none
    \retval     none
*/
void rtc_tamper0_pin_map(uint32_t rtc_af)
{
    RTC_TAMP &= ~(RTC_TAMP_TP0EN | RTC_TAMP_TP0SEL);
    RTC_TAMP |= rtc_af;
}
/*!
    \brief      enable specified RTC interrupt
    \param[in]  interrupt: specify which interrupt source to be enabled
      \arg        RTC_INT_TIMESTAMP: timestamp interrupt
      \arg        RTC_INT_ALARM0: alarm0 interrupt
      \arg        RTC_INT_ALARM1: alarm1 interrupt
      \arg        RTC_INT_TAMP: tamp interrupt
      \arg        RTC_INT_WAKEUP: wakeup timer interrupt
    \param[out] none
    \retval     none
*/
void rtc_interrupt_enable(uint32_t interrupt)
{  
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
 
    /* enable the interrupts in RTC_CTL register */
    RTC_CTL |= (uint32_t)(interrupt & (uint32_t)~RTC_TAMP_TPIE);
    /* enable the interrupts in RTC_TAMP register */
    RTC_TAMP |= (uint32_t)(interrupt & RTC_TAMP_TPIE);
    
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY; 
}

/*!
    \brief      disble specified RTC interrupt
    \param[in]  interrupt: specify which interrupt source to be disabled
      \arg        RTC_INT_TIMESTAMP: timestamp interrupt
      \arg        RTC_INT_ALARM0: alarm interrupt
      \arg        RTC_INT_ALARM1: alarm interrupt
      \arg        RTC_INT_TAMP: tamp interrupt
      \arg        RTC_INT_WAKEUP: wakeup timer interrupt
    \param[out] none
    \retval     none
*/
void rtc_interrupt_disable(uint32_t interrupt)
{  
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
 
    /* disable the interrupts in RTC_CTL register */
    RTC_CTL &= (uint32_t)~(interrupt & (uint32_t)~RTC_TAMP_TPIE);
    /* disable the interrupts in RTC_TAMP register */
    RTC_TAMP &= (uint32_t)~(interrupt & RTC_TAMP_TPIE);

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      check specified flag
    \param[in]  flag: specify which flag to check
      \arg        RTC_STAT_RECPF: recalibration pending flag
      \arg        RTC_STAT_TP1F: tamper 1 event flag
      \arg        RTC_STAT_TP0F: tamper 0 event flag
      \arg        RTC_STAT_TSOVRF: time-stamp overflow event flag
      \arg        RTC_STAT_TSF: time-stamp event flag
      \arg        RTC_STAT_ALRM0F: alarm0 event flag
      \arg        RTC_STAT_ALRM1F: alarm1 event flag
      \arg        RTC_STAT_WTF: wakeup timer event flag
      \arg        RTC_STAT_INITF: init mode event flag
      \arg        RTC_STAT_RSYNF: time and date registers synchronized event flag
      \arg        RTC_STAT_YCM: year parameter configured event flag
      \arg        RTC_STAT_SOPF: shift operation pending flag
      \arg        RTC_STAT_ALRM0WF: alarm0 writen available flag
      \arg        RTC_STAT_ALRM1WF: alarm1 writen available flag
      \arg        RTC_STAT_WTWF: wakeup timer writen available flag
    \param[out] none
    \retval     FlagStatus: SET or RESET
*/
FlagStatus rtc_flag_get(uint32_t flag)
{
    FlagStatus flag_state = RESET;
    
    if ((uint32_t)RESET != (RTC_STAT & flag)){
        flag_state = SET;
    }
    return flag_state;
}

/*!
    \brief      clear specified flag
    \param[in]  flag: specify which flag to clear
      \arg        RTC_STAT_TP1F: tamper 1 event flag
      \arg        RTC_STAT_TP0F: tamper 0 event flag
      \arg        RTC_STAT_TSOVRF: time-stamp overflow event flag
      \arg        RTC_STAT_TSF: time-stamp event flag
      \arg        RTC_STAT_WTF: time-stamp event flag
      \arg        RTC_STAT_ALRM0F: alarm0 event flag
      \arg        RTC_STAT_ALRM1F: alarm1 event flag
      \arg        RTC_STAT_RSYNF: time and date registers synchronized event flag
    \param[out] none
    \retval     none
*/
void rtc_flag_clear(uint32_t flag)
{
    RTC_STAT &= (uint32_t)(~flag);  
}

/*!
    \brief      configure rtc alarm output source
    \param[in]  source: specify signal to output
      \arg        RTC_ALARM0_HIGH: when the  alarm0 flag is set, the output pin is high
      \arg        RTC_ALARM0_LOW: when the  alarm0 flag is set, the output pin is low
      \arg        RTC_ALARM1_HIGH: when the  alarm1 flag is set, the output pin is high
      \arg        RTC_ALARM1_LOW: when the  alarm1 flag is set, the output pin is low
      \arg        RTC_WAKEUP_HIGH: when the  wakeup flag is set, the output pin is high
      \arg        RTC_WAKEUP_LOW: when the  wakeup flag is set, the output pin is low
    \param[in]  mode: specify the output pin mode when output alarm signal
      \arg        RTC_ALARM_OUTPUT_OD: open drain mode
      \arg        RTC_ALARM_OUTPUT_PP: push pull mode
    \param[out] none
    \retval     none
*/
void rtc_alarm_output_config(uint32_t source, uint32_t mode)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    RTC_CTL &= ~(RTC_CTL_OS | RTC_CTL_OPOL);
    RTC_TAMP &= ~RTC_TAMP_AOT;

    RTC_CTL |= (uint32_t)(source);
    /* alarm output */
    RTC_TAMP |= (uint32_t)(mode);

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      configure rtc calibration output source
    \param[in]  source: specify signal to output
      \arg        RTC_CALIBRATION_512HZ: when the LSE freqency is 32768Hz and the RTC_PSC 
                                         is the default value, output 512Hz signal
      \arg        RTC_CALIBRATION_1HZ: when the LSE freqency is 32768Hz and the RTC_PSC 
                                       is the default value, output 512Hz signal
    \param[out] none
    \retval     none
*/
void rtc_calibration_output_config(uint32_t source)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    RTC_CTL &= (uint32_t)~(RTC_CTL_COEN | RTC_CTL_COS);

    RTC_CTL |= (uint32_t)(source);
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}


/*!
    \brief      adjust the daylight saving time by adding or substracting one hour from the current time
    \param[in]  operation: hour adjustment operation
      \arg        RTC_CTL_A1H: add one hour
      \arg        RTC_CTL_S1H: substract one hour
    \param[out] none
    \retval     none
*/
void rtc_hour_adjust(uint32_t operation)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    
    RTC_CTL |= (uint32_t)(operation);

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      adjust RTC second or subsecond value of current time
    \param[in]  add: add 1s to current time or not
      \arg        RTC_SHIFT_ADD1S_RESET: no effect
      \arg        RTC_SHIFT_ADD1S_SET: add 1s to current time
    \param[in]  minus: number of subsecond to minus from current time(0x0 - 0x7FFF)
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_second_adjust(uint32_t add, uint32_t minus)
{
    volatile uint32_t time_index = RTC_SHIFTCTL_TIMEOUT;
    ErrStatus error_status = ERROR;
    uint32_t flag_status = RESET;
    uint32_t temp=0U;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    
    /* check if a shift operation is ongoing */    
    do{
        flag_status = RTC_STAT & RTC_STAT_SOPF;
    }while((--time_index > 0U) && ((uint32_t)RESET != flag_status));
    
    /* check if the function of reference clock detection is disabled */
    temp = RTC_CTL & RTC_CTL_REFEN;
    if((RESET == flag_status) && (RESET == temp)){  
        RTC_SHIFTCTL = (uint32_t)(add | SHIFTCTL_SFS(minus));
        error_status = rtc_register_sync_wait();        
    }

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      enable RTC bypass shadow registers function
    \param[in]  none
    \param[out] none
    \retval     none
*/
void rtc_bypass_shadow_enable(void)
{ 
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    RTC_CTL |= RTC_CTL_BPSHAD;

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      disable RTC bypass shadow registers function
    \param[in]  none
    \param[out] none
    \retval     none
*/
void rtc_bypass_shadow_disable(void)
{ 
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    RTC_CTL &= ~RTC_CTL_BPSHAD;

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      enable RTC reference clock detection function
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_refclock_detection_enable(void)
{
    ErrStatus error_status = ERROR;
    
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    /* enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){
        RTC_CTL |= (uint32_t)RTC_CTL_REFEN;
        /* exit init mode */
        rtc_init_mode_exit();
    }

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      disable RTC reference clock detection function
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_refclock_detection_disable(void)
{
    ErrStatus error_status = ERROR;
    
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;

    /* enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){ 
        RTC_CTL &= (uint32_t)~RTC_CTL_REFEN;
        /* exit init mode */
        rtc_init_mode_exit();
    }

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      enable RTC auto wakeup function
    \param[in]  none
    \param[out] none
    \retval     none
*/
void rtc_wakeup_enable(void)
{
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2; 

    RTC_CTL |= RTC_CTL_WTEN;

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
}

/*!
    \brief      disable RTC auto wakeup function
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_wakeup_disable(void)
{
    ErrStatus error_status = ERROR;
    volatile uint32_t time_index = RTC_WTWF_TIMEOUT;
    uint32_t flag_status = RESET;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    RTC_CTL &= ~RTC_CTL_WTEN;
    /* wait until the WTWF flag to be set */
    do{
        flag_status = RTC_STAT & RTC_STAT_WTWF;
    }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));

    if ((uint32_t)RESET == flag_status){
        error_status = ERROR;
    }else{
        error_status = SUCCESS;
    }
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
    return error_status;
}

/*!
    \brief      set RTC auto wakeup timer clock
    \param[in]  wakeup_clock:
      \arg        WAKEUP_RTCCK_DIV16: RTC auto wakeup timer clock is RTC clock divided by 16 
      \arg        WAKEUP_RTCCK_DIV8: RTC auto wakeup timer clock is RTC clock divided by 8 
      \arg        WAKEUP_RTCCK_DIV4: RTC auto wakeup timer clock is RTC clock divided by 4 
      \arg        WAKEUP_RTCCK_DIV2: RTC auto wakeup timer clock is RTC clock divided by 2 
      \arg        WAKEUP_CKSPRE: RTC auto wakeup timer clock is ckspre
      \arg        WAKEUP_CKSPRE_2EXP16: RTC auto wakeup timer clock is ckspre and wakeup timer add 2exp16 
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_wakeup_clock_set(uint8_t wakeup_clock)
{
    ErrStatus error_status = ERROR;
    volatile uint32_t time_index = RTC_WTWF_TIMEOUT;
    uint32_t flag_status = RESET;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2; 
    /* only when RTC_CTL_WTEN=0 and RTC_STAT_WTWF=1 can write RTC_CTL[2£º0] */
    /* wait until the WTWF flag to be set */
    do{
        flag_status = RTC_STAT & RTC_STAT_WTWF;
    }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));

    if ((uint32_t)RESET == flag_status){
        error_status = ERROR;
    }else{
        RTC_CTL &= (uint32_t)~ RTC_CTL_WTCS;
        RTC_CTL |= (uint32_t)wakeup_clock;
        error_status = SUCCESS;
    }
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
    
    return error_status;
}

/*!
    \brief      set wakeup timer value
    \param[in]  wakeup_timer: 0x0000-0xffff
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_wakeup_timer_set(uint16_t wakeup_timer)
{
    ErrStatus error_status = ERROR;
    volatile uint32_t time_index = RTC_WTWF_TIMEOUT;
    uint32_t flag_status = RESET;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    /* wait until the WTWF flag to be set */
    do{
        flag_status = RTC_STAT & RTC_STAT_WTWF;
    }while((--time_index > 0U) && ((uint32_t)RESET == flag_status));

    if ((uint32_t)RESET == flag_status){
        error_status = ERROR;
    }else{
        RTC_WUT = (uint32_t)wakeup_timer;
        error_status = SUCCESS;
    }
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
    return error_status;
}

/*!
    \brief      get wakeup timer value
    \param[in]  none
    \param[out] none
    \retval     wakeup timer value
*/
 uint16_t rtc_wakeup_timer_get(void)
{
    return (uint16_t)RTC_WUT;
}

/*!
    \brief      configure RTC smooth calibration
    \param[in]  window: select calibration window
      \arg        RTC_CALIBRATION_WINDOW_32S: 2exp20 RTCCLK cycles, 32s if RTCCLK = 32768 Hz
      \arg        RTC_CALIBRATION_WINDOW_16S: 2exp19 RTCCLK cycles, 16s if RTCCLK = 32768 Hz
      \arg        RTC_CALIBRATION_WINDOW_8S: 2exp18 RTCCLK cycles, 8s if RTCCLK = 32768 Hz
    \param[in]  plus: add RTC clock or not
      \arg        RTC_CALIBRATION_PLUS_SET: add one RTC clock every 2048 rtc clock
      \arg        RTC_CALIBRATION_PLUS_RESET: no effect
    \param[in]  minus: the RTC clock to minus during the calibration window(0x0 - 0x1FF)
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_smooth_calibration_config(uint32_t window, uint32_t plus, uint32_t minus)
{
    volatile uint32_t time_index = RTC_HRFC_TIMEOUT;
    ErrStatus error_status = ERROR;
    uint32_t flag_status = RESET;
    
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;    
    
    /* check if a smooth calibration operation is ongoing */        
    do{
        flag_status = RTC_STAT & RTC_STAT_SCPF;
    }while((--time_index > 0U) && ((uint32_t)RESET != flag_status));
    
    if((uint32_t)RESET == flag_status){
        RTC_HRFC = (uint32_t)(window | plus | HRFC_CMSK(minus));
        error_status = SUCCESS;
    }

    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;

    return error_status;
}

/*!
    \brief      enable RTC coarse calibration
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_coarse_calibration_enable(void)
{
    ErrStatus error_status = ERROR;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    /* enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){ 
        RTC_CTL |= (uint32_t)RTC_CTL_CCEN;
        /* exit init mode */
        rtc_init_mode_exit();
    }
    
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
    return error_status;
}

/*!
    \brief      disable RTC coarse calibration
    \param[in]  none
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_coarse_calibration_disable(void)
{
    ErrStatus error_status = ERROR;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;    
    /* enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){ 
        RTC_CTL &= (uint32_t)~RTC_CTL_CCEN;
        /* exit init mode */
        rtc_init_mode_exit();
    }
    
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;	
    return error_status;
}

/*!
    \brief      config coarse calibration direction and step
    \param[in]  direction: CALIB_INCREASE or CALIB_DECREASE      
    \param[in]  step: 0x00-0x1F
                COSD=0:
                  0x00:+0 PPM
                  0x01:+4 PPM
                  0x02:+8 PPM
                  ....
                  0x1F:+126 PPM
                COSD=1:
                  0x00:-0 PPM
                  0x01:-2 PPM
                  0x02:-4 PPM
                  ....
                  0x1F:-63 PPM
    \param[out] none
    \retval     ErrStatus: ERROR or SUCCESS
*/
ErrStatus rtc_coarse_calibration_config(uint8_t direction, uint8_t step)
{
    ErrStatus error_status = ERROR;
    /* disable the write protection */
    RTC_WPK = RTC_UNLOCK_KEY1;
    RTC_WPK = RTC_UNLOCK_KEY2;
    
    /* enter init mode */
    error_status = rtc_init_mode_enter();

    if(ERROR != error_status){ 
        if(CALIB_DECREASE == direction){
            RTC_COSC |= (uint32_t)RTC_COSC_COSD;
        }else{
            RTC_COSC &= (uint32_t)~RTC_COSC_COSD;
        }
        RTC_COSC &= ~RTC_COSC_COSS;
        RTC_COSC |= (uint32_t)((uint32_t)step & 0x1FU);
        /* exit init mode */
        rtc_init_mode_exit();
    }
    
    /* enable the write protection */
    RTC_WPK = RTC_LOCK_KEY;
    
    return error_status;
}