Real-Time Clock (RTC)

See Quickstart guide for SAM RTC driver.

The RTC provides a full binary-coded decimal (BCD) clock that includes century (19/20), year (with leap years), month, date, day, hour, minute and second.

Macros
#define	BCD_FACTOR   10
#define	BCD_MASK   0xfu
#define	BCD_SHIFT   4
#define	RTC_WP_KEY   (0x525443)

Functions
void	rtc_clear_date_alarm (Rtc *p_rtc)
	Clear the RTC date alarm setting. More...
void	rtc_clear_status (Rtc *p_rtc, uint32_t ul_clear)
	Set the RTC SCCR to clear status bits. More...
void	rtc_clear_time_alarm (Rtc *p_rtc)
	Clear the RTC time alarm setting. More...
void	rtc_disable_interrupt (Rtc *p_rtc, uint32_t ul_sources)
	Disable RTC interrupts. More...
void	rtc_enable_interrupt (Rtc *p_rtc, uint32_t ul_sources)
	Enable RTC interrupts. More...
uint32_t	rtc_get_calendar_mode (Rtc *p_rtc)
	Get the RTC calendar mode. More...
void	rtc_get_date (Rtc *p_rtc, uint32_t *pul_year, uint32_t *pul_month, uint32_t *pul_day, uint32_t *pul_week)
	Get the RTC date value. More...
uint32_t	rtc_get_hour_mode (Rtc *p_rtc)
	Get the RTC hour mode. More...
uint32_t	rtc_get_interrupt_mask (Rtc *p_rtc)
	Read RTC interrupt mask. More...
uint32_t	rtc_get_milliseconds (Rtc *p_rtc)
	Get the RTC milliseconds value. More...
uint32_t	rtc_get_status (Rtc *p_rtc)
	Get the RTC status. More...
void	rtc_get_tamper_date (Rtc *p_rtc, uint32_t *pul_year, uint32_t *pul_month, uint32_t *pul_day, uint32_t *pul_week, uint8_t reg_num)
	Get the RTC tamper date. More...
uint32_t	rtc_get_tamper_event_counter (Rtc *p_rtc)
	Get the RTC tamper event counter. More...
uint32_t	rtc_get_tamper_source (Rtc *p_rtc, uint8_t reg_num)
	Get the RTC tamper source. More...
void	rtc_get_tamper_time (Rtc *p_rtc, uint32_t *pul_hour, uint32_t *pul_minute, uint32_t *pul_second, uint8_t reg_num)
	Get the RTC tamper time value. More...
void	rtc_get_time (Rtc *p_rtc, uint32_t *pul_hour, uint32_t *pul_minute, uint32_t *pul_second)
	Get the RTC time value. More...
uint32_t	rtc_get_valid_entry (Rtc *p_rtc)
	Get the RTC valid entry. More...
bool	rtc_is_tamper_occur_in_backup_mode (Rtc *p_rtc, uint8_t reg_num)
	Check the system is in backup mode when RTC tamper event happen. More...
void	rtc_set_calendar_event (Rtc *p_rtc, uint32_t ul_selection)
	Set the RTC calendar event selection. More...
void	rtc_set_calendar_mode (Rtc *p_rtc, uint32_t ul_mode)
	Set the RTC calendar mode. More...
void	rtc_set_calibration (Rtc *p_rtc, uint32_t ul_direction_ppm, uint32_t ul_correction, uint32_t ul_range_ppm)
	Set the RTC calibration. More...
uint32_t	rtc_set_date (Rtc *p_rtc, uint32_t ul_year, uint32_t ul_month, uint32_t ul_day, uint32_t ul_week)
	Set the RTC date. More...
uint32_t	rtc_set_date_alarm (Rtc *p_rtc, uint32_t ul_month_flag, uint32_t ul_month, uint32_t ul_day_flag, uint32_t ul_day)
	Set the RTC alarm date value. More...
void	rtc_set_hour_mode (Rtc *p_rtc, uint32_t ul_mode)
	Set the RTC hour mode. More...
void	rtc_set_pulse_parameter (Rtc *p_rtc, uint32_t ul_time_high, uint32_t ul_period)
	Set the pulse output waveform parameters. More...
uint32_t	rtc_set_time (Rtc *p_rtc, uint32_t ul_hour, uint32_t ul_minute, uint32_t ul_second)
	Set the RTC time value. More...
uint32_t	rtc_set_time_alarm (Rtc *p_rtc, uint32_t ul_hour_flag, uint32_t ul_hour, uint32_t ul_minute_flag, uint32_t ul_minute, uint32_t ul_second_flag, uint32_t ul_second)
	Set the RTC alarm time value. More...
void	rtc_set_time_event (Rtc *p_rtc, uint32_t ul_selection)
	Set the RTC time event selection. More...
void	rtc_set_waveform (Rtc *p_rtc, uint32_t ul_channel, uint32_t ul_value)
	Set the RTC output waveform. More...
void	rtc_set_writeprotect (Rtc *p_rtc, uint32_t ul_enable)
	Enable or disable write protection of RTC registers. More...

#define BCD_FACTOR   10

Referenced by rtc_get_date(), rtc_get_tamper_date(), rtc_get_tamper_time(), rtc_get_time(), rtc_set_date(), rtc_set_date_alarm(), rtc_set_time(), and rtc_set_time_alarm().

#define BCD_MASK   0xfu

Referenced by rtc_get_date(), rtc_get_tamper_date(), rtc_get_tamper_time(), and rtc_get_time().

#define BCD_SHIFT   4

Referenced by rtc_get_date(), rtc_get_tamper_date(), rtc_get_tamper_time(), rtc_get_time(), rtc_set_date(), rtc_set_date_alarm(), rtc_set_time(), and rtc_set_time_alarm().

#define RTC_WP_KEY   (0x525443)

Referenced by rtc_set_writeprotect().

void rtc_clear_date_alarm

(

Rtc *

p_rtc

)

Clear the RTC date alarm setting.

Parameters

p_rtc

Pointer to an RTC instance.

Referenced by main().

void rtc_clear_status	(	Rtc *	p_rtc,
		uint32_t	ul_clear
	)

Set the RTC SCCR to clear status bits.

Parameters

p_rtc	Pointer to an RTC instance.
ul_clear	Some flag bits which will be cleared.

Referenced by RTC_Handler().

void rtc_clear_time_alarm

(

Rtc *

p_rtc

)

Clear the RTC time alarm setting.

Parameters

p_rtc

Pointer to an RTC instance.

Referenced by main().

void rtc_disable_interrupt	(	Rtc *	p_rtc,
		uint32_t	ul_sources
	)

Disable RTC interrupts.

Parameters

p_rtc	Pointer to an RTC instance.
ul_sources	Interrupts to be disabled.

Referenced by RTC_Handler().

void rtc_enable_interrupt	(	Rtc *	p_rtc,
		uint32_t	ul_sources
	)

Enable RTC interrupts.

Parameters

p_rtc	Pointer to an RTC instance.
ul_sources	Interrupts to be enabled.

Referenced by main(), and RTC_Handler().

uint32_t rtc_get_calendar_mode

(

Rtc *

p_rtc

)

Get the RTC calendar mode.

Note

This function is only available on SAM3S8/3SD8/4S/4N/4C/G devices.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

1 for Persian calendar, 0 for Gregorian calendar.

void rtc_get_date	(	Rtc *	p_rtc,
		uint32_t *	pul_year,
		uint32_t *	pul_month,
		uint32_t *	pul_day,
		uint32_t *	pul_week
	)

Get the RTC date value.

Parameters

p_rtc	Pointer to an RTC instance.
pul_year	Current year.
pul_month	Current month.
pul_day	Current day.
pul_week	Current day in current week.

References BCD_FACTOR, BCD_MASK, and BCD_SHIFT.

Referenced by refresh_display().

uint32_t rtc_get_hour_mode

(

Rtc *

p_rtc

)

Get the RTC hour mode.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

1 for 12-hour mode, 0 for 24-hour mode.

uint32_t rtc_get_interrupt_mask

(

Rtc *

p_rtc

)

Read RTC interrupt mask.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

The interrupt mask value.

uint32_t rtc_get_milliseconds

(

Rtc *

p_rtc

)

Get the RTC milliseconds value.

Note

This function is only available on SAMG55 devices.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

Number of 1/1024 seconds elapsed within one second.

uint32_t rtc_get_status

(

Rtc *

p_rtc

)

Get the RTC status.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

Status of the RTC.

Referenced by RTC_Handler().

void rtc_get_tamper_date	(	Rtc *	p_rtc,
		uint32_t *	pul_year,
		uint32_t *	pul_month,
		uint32_t *	pul_day,
		uint32_t *	pul_week,
		uint8_t	reg_num
	)

Get the RTC tamper date.

Note

This function is only available on SAM4C devices.

This function should be called before rtc_get_tamper_source() function call, Otherwise the tamper date will be cleared.

Parameters

p_rtc	Pointer to an RTC instance.
pul_year	Current year.
pul_month	Current month.
pul_day	Current day.
pul_week	Current day in current week.
reg_num	Current tamper register set number.

References BCD_FACTOR, BCD_MASK, and BCD_SHIFT.

uint32_t rtc_get_tamper_event_counter

(

Rtc *

p_rtc

)

Get the RTC tamper event counter.

Note

This function is only available on SAM4C devices.

This function should be called before rtc_get_tamper_source() function call, Otherwise the tamper event counter will be cleared.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

Tamper event counter

uint32_t rtc_get_tamper_source	(	Rtc *	p_rtc,
		uint8_t	reg_num
	)

Get the RTC tamper source.

Note

This function is only available on SAM4C devices.

Parameters

p_rtc	Pointer to an RTC instance.
reg_num	Current tamper register set number.

Returns

Tamper source.

void rtc_get_tamper_time	(	Rtc *	p_rtc,
		uint32_t *	pul_hour,
		uint32_t *	pul_minute,
		uint32_t *	pul_second,
		uint8_t	reg_num
	)

Get the RTC tamper time value.

Note

This function is only available on SAM4C devices.

This function should be called before rtc_get_tamper_source() function call, Otherwise the tamper time will be cleared.

Parameters

p_rtc	Pointer to an RTC instance.
pul_hour	Current hour, 24-hour mode.
pul_minute	Current minute.
pul_second	Current second.
reg_num	Current tamper register set number.

References BCD_FACTOR, BCD_MASK, and BCD_SHIFT.

void rtc_get_time	(	Rtc *	p_rtc,
		uint32_t *	pul_hour,
		uint32_t *	pul_minute,
		uint32_t *	pul_second
	)

Get the RTC time value.

Parameters

p_rtc	Pointer to an RTC instance.
pul_hour	Current hour, 24-hour mode.
pul_minute	Current minute.
pul_second	Current second.

References BCD_FACTOR, BCD_MASK, and BCD_SHIFT.

Referenced by refresh_display().

uint32_t rtc_get_valid_entry

(

Rtc *

p_rtc

)

Get the RTC valid entry.

Parameters

p_rtc

Pointer to an RTC instance.

Returns

0 for no invalid data, else has contained invalid data.

bool rtc_is_tamper_occur_in_backup_mode	(	Rtc *	p_rtc,
		uint8_t	reg_num
	)

Check the system is in backup mode when RTC tamper event happen.

Note

This function is only available on SAM4C devices.

This function should be called before rtc_get_tamper_source() function call, Otherwise the flag indicates tamper occur in backup mode will be cleared.

Parameters

p_rtc	Pointer to an RTC instance.
reg_num	Current tamper register set number.

Returns

True - The system is in backup mode when the tamper event occurs. Flase - The system is different from backup mode.

void rtc_set_calendar_event	(	Rtc *	p_rtc,
		uint32_t	ul_selection
	)

Set the RTC calendar event selection.

Parameters

p_rtc	Pointer to an RTC instance.
ul_selection	Calendar event selection to be enabled..

void rtc_set_calendar_mode	(	Rtc *	p_rtc,
		uint32_t	ul_mode
	)

Set the RTC calendar mode.

Note

This function is only available on SAM3S8/3SD8/4S/4N/4C/G devices.

Parameters

p_rtc	Pointer to an RTC instance.
ul_mode	1 for Persian mode,0 for Gregorian mode.

void rtc_set_calibration	(	Rtc *	p_rtc,
		uint32_t	ul_direction_ppm,
		uint32_t	ul_correction,
		uint32_t	ul_range_ppm
	)

Set the RTC calibration.

Note

This function is only available on SAM3S8/3SD8/4S/4N/4C/G devices.

Parameters

p_rtc	Pointer to an RTC instance.
ul_direction_ppm	Positive/negative correction.
ul_correction	Correction value.
ul_range_ppm	Low/high range correction.

uint32_t rtc_set_date	(	Rtc *	p_rtc,
		uint32_t	ul_year,
		uint32_t	ul_month,
		uint32_t	ul_day,
		uint32_t	ul_week
	)

Set the RTC date.

Parameters

p_rtc	Pointer to an RTC instance.
ul_year	Current year.
ul_month	Current month.
ul_day	Current day.
ul_week	Current day in current week.

Returns

0 for OK, else invalid setting.

References BCD_FACTOR, and BCD_SHIFT.

Referenced by main().

uint32_t rtc_set_date_alarm	(	Rtc *	p_rtc,
		uint32_t	ul_month_flag,
		uint32_t	ul_month,
		uint32_t	ul_day_flag,
		uint32_t	ul_day
	)

Set the RTC alarm date value.

Parameters

p_rtc	Pointer to an RTC instance.
ul_month_flag	1 for setting, 0 for not setting.
ul_month	Alarm month value.
ul_day_flag	1 for setting, 0 for not setting.
ul_day	Alarm day value.

Returns

0 for OK, else invalid setting.

References BCD_FACTOR, and BCD_SHIFT.

Referenced by main().

void rtc_set_hour_mode	(	Rtc *	p_rtc,
		uint32_t	ul_mode
	)

Set the RTC hour mode.

Parameters

p_rtc	Pointer to an RTC instance.
ul_mode	1 for 12-hour mode, 0 for 24-hour mode.

Referenced by main().

void rtc_set_pulse_parameter	(	Rtc *	p_rtc,
		uint32_t	ul_time_high,
		uint32_t	ul_period
	)

Set the pulse output waveform parameters.

Note

This function is only available on SAM3S8/3SD8/4S/4C/V/S/E devices.

Parameters

p_rtc	Pointer to an RTC instance.
ul_time_high	High duration of the output pulse.
ul_period	Period of the output pulse.

uint32_t rtc_set_time	(	Rtc *	p_rtc,
		uint32_t	ul_hour,
		uint32_t	ul_minute,
		uint32_t	ul_second
	)

Set the RTC time value.

Parameters

p_rtc	Pointer to an RTC instance.
ul_hour	Current hour, 24-hour mode.
ul_minute	Current minute.
ul_second	Current second.

Returns

0 for OK, else invalid setting.

References BCD_FACTOR, and BCD_SHIFT.

Referenced by main().

uint32_t rtc_set_time_alarm	(	Rtc *	p_rtc,
		uint32_t	ul_hour_flag,
		uint32_t	ul_hour,
		uint32_t	ul_minute_flag,
		uint32_t	ul_minute,
		uint32_t	ul_second_flag,
		uint32_t	ul_second
	)

Set the RTC alarm time value.

Parameters

p_rtc	Pointer to an RTC instance.
ul_hour_flag	1 for setting, 0 for not setting.
ul_hour	Alarm hour value, 24-hour mode.
ul_minute_flag	1 for setting, 0 for not setting.
ul_minute	Alarm minute value.
ul_second_flag	1 for setting, 0 for not setting.
ul_second	Alarm second value.

Returns

0 for OK, else invalid setting.

References BCD_FACTOR, and BCD_SHIFT.

Referenced by main().

void rtc_set_time_event	(	Rtc *	p_rtc,
		uint32_t	ul_selection
	)

Set the RTC time event selection.

Parameters

p_rtc	Pointer to an RTC instance.
ul_selection	Time event selection to be enabled.

void rtc_set_waveform	(	Rtc *	p_rtc,
		uint32_t	ul_channel,
		uint32_t	ul_value
	)

Set the RTC output waveform.

Note

This function is only available on SAM3S8/3SD8/4S/4C/G/V/S/E devices.

Parameters

p_rtc	Pointer to an RTC instance.
ul_channel	Output channel selection.
ul_value	Output source selection value.

Referenced by main().

void rtc_set_writeprotect	(	Rtc *	p_rtc,
		uint32_t	ul_enable
	)

Enable or disable write protection of RTC registers.

Note

This function is only available on SAM3N/3U/3XA devices.

Parameters

p_rtc	Pointer to an RTC instance.
ul_enable	1 to enable, 0 to disable.

References RTC_WP_KEY.