File syn_rtc.c¶

FileList > drivers > syn_rtc.c

RTC driver implementation — port delegation + epoch math.

#include "../util/syn_assert.h"
#include "syn_rtc.h"

Public Static Attributes¶

Type	Name
const uint8_t	s_days_in_month = `/* multi line expression /` Days per month (non-leap year).*
int32_t	s_drift_ppm = `0` Calibrated clock drift compensation in parts-per-million (PPM).

Public Functions¶

Type	Name
void	syn_rtc_from_epoch (uint32_t epoch, SYN_RTC_DateTime * dt) Convert a Unix epoch timestamp to a date/time.
SYN_Status	syn_rtc_get (SYN_RTC_DateTime * dt) Read the current date/time.
SYN_Status	syn_rtc_init (void) Initialize the RTC peripheral.
bool	syn_rtc_is_valid (const SYN_RTC_DateTime * dt) Check whether all fields of a SYN_RTC_DateTime are in range.
SYN_Status	syn_rtc_schedule_alarm_seconds (uint32_t seconds_from_now, SYN_RTC_DateTime * alarm_dt) Schedule an alarm relative to current time by seconds.
SYN_Status	syn_rtc_set (const SYN_RTC_DateTime * dt) Set the RTC to a new date/time.
SYN_Status	syn_rtc_set_alarm (const SYN_RTC_DateTime * dt) Set the target alarm date/time on the RTC.
void	syn_rtc_set_drift_ppm (int32_t drift_ppm) Set the RTC clock drift compensation in Parts-Per-Million (PPM).
uint32_t	syn_rtc_to_epoch (const SYN_RTC_DateTime * dt) Convert a date/time to a Unix epoch timestamp.

Public Static Functions¶

Type	Name
uint8_t	rtc_days_in_month (uint8_t month, uint16_t year) Get days in a given month.
bool	rtc_is_leap (uint16_t year) Test if a year is a leap year.

Public Static Attributes Documentation¶

variable s_days_in_month¶

Days per month (non-leap year).

const uint8_t s_days_in_month[12];

variable s_drift_ppm¶

Calibrated clock drift compensation in parts-per-million (PPM).

int32_t s_drift_ppm;

Public Functions Documentation¶

function syn_rtc_from_epoch¶

Convert a Unix epoch timestamp to a date/time.

void syn_rtc_from_epoch (
    uint32_t epoch,
    SYN_RTC_DateTime * dt
)

Parameters:

epoch Seconds since 1970-01-01 00:00:00 UTC.
dt Output. Must not be NULL.

function syn_rtc_get¶

Read the current date/time.

SYN_Status syn_rtc_get (
    SYN_RTC_DateTime * dt
)

Parameters:

dt Output, must not be NULL.

Returns:

SYN_OK on success, SYN_ERROR on hardware failure.

function syn_rtc_init¶

Initialize the RTC peripheral.

SYN_Status syn_rtc_init (
    void
)

Returns:

SYN_OK on success, SYN_ERROR on failure.

function syn_rtc_is_valid¶

Check whether all fields of a SYN_RTC_DateTime are in range.

bool syn_rtc_is_valid (
    const SYN_RTC_DateTime * dt
)

Parameters:

dt Date/time to validate. Must not be NULL.

Returns:

true if valid, false if any field is out of range.

function syn_rtc_schedule_alarm_seconds¶

Schedule an alarm relative to current time by seconds.

SYN_Status syn_rtc_schedule_alarm_seconds (
    uint32_t seconds_from_now,
    SYN_RTC_DateTime * alarm_dt
)

Parameters:

seconds_from_now Seconds to add to current time.
alarm_dt Output target alarm date/time structure.

Returns:

SYN_OK on success, error code otherwise.

function syn_rtc_set¶

Set the RTC to a new date/time.

SYN_Status syn_rtc_set (
    const SYN_RTC_DateTime * dt
)

Validates all fields before writing to hardware.

Parameters:

dt New time. Must not be NULL and must pass syn_rtc_is_valid().

Returns:

SYN_OK on success, SYN_INVALID_PARAM if fields are out of range, SYN_ERROR on hardware failure.

function syn_rtc_set_alarm¶

Set the target alarm date/time on the RTC.

SYN_Status syn_rtc_set_alarm (
    const SYN_RTC_DateTime * dt
)

Parameters:

dt Target alarm date/time. Must be valid.

Returns:

SYN_OK on success, error code otherwise.

function syn_rtc_set_drift_ppm¶

Set the RTC clock drift compensation in Parts-Per-Million (PPM).

void syn_rtc_set_drift_ppm (
    int32_t drift_ppm
)

Parameters:

drift_ppm Drift in Parts-Per-Million (+ = fast, - = slow).

function syn_rtc_to_epoch¶

Convert a date/time to a Unix epoch timestamp.

uint32_t syn_rtc_to_epoch (
    const SYN_RTC_DateTime * dt
)

Epoch = seconds since 1970-01-01 00:00:00 UTC. Leap seconds are not accounted for (standard POSIX convention).

Parameters:

dt Date/time to convert. Must be valid.

Returns:

Seconds since Unix epoch.

Public Static Functions Documentation¶

function rtc_days_in_month¶

Get days in a given month.

static uint8_t rtc_days_in_month (
    uint8_t month,
    uint16_t year
)

Parameters:

month Month (1–12).
year Gregorian year.

Returns:

Day count.

function rtc_is_leap¶

Test if a year is a leap year.

static bool rtc_is_leap (
    uint16_t year
)

Parameters:

year Gregorian year.

Returns:

true if leap year.

The documentation for this class was generated from the following file src/syntropic/drivers/syn_rtc.c