time.h File Reference

#include "pico.h"
#include "hardware/timer.h"

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Data Structures
struct	repeating_timer
	Information about a repeating timer. More...

Macros
#define	PARAM_ASSERTIONS_ENABLED_PICO_TIME   0
#define	PICO_TIME_SLEEP_OVERHEAD_ADJUST_US   6
#define	PICO_TIME_DEFAULT_ALARM_POOL_DISABLED   0
	If 1 then the default alarm pool is disabled (so no timer_alarm is claimed for the pool).
#define	PICO_TIME_DEFAULT_ALARM_POOL_HARDWARE_ALARM_NUM   3
	Selects which timer_alarm is used for the default alarm pool.
#define	PICO_TIME_DEFAULT_ALARM_POOL_MAX_TIMERS   16
	Selects the maximum number of concurrent timers in the default alarm pool.

Typedefs
typedef int32_t	alarm_id_t
	The identifier for an alarm.
typedef int64_t(*	alarm_callback_t) (alarm_id_t id, void *user_data)
	User alarm callback.
typedef struct alarm_pool	alarm_pool_t
typedef void	alarm_pool_timer_t
typedef struct repeating_timer	repeating_timer_t
typedef bool(*	repeating_timer_callback_t) (repeating_timer_t *rt)
	Callback for a repeating timer.

Functions
static absolute_time_t	get_absolute_time (void)
	Return a representation of the current time.
static uint32_t	us_to_ms (uint64_t us)
static uint32_t	to_ms_since_boot (absolute_time_t t)
	Convert a timestamp into a number of milliseconds since boot.
static absolute_time_t	delayed_by_us (const absolute_time_t t, uint64_t us)
	Return a timestamp value obtained by adding a number of microseconds to another timestamp.
static absolute_time_t	delayed_by_ms (const absolute_time_t t, uint32_t ms)
	Return a timestamp value obtained by adding a number of milliseconds to another timestamp.
static absolute_time_t	make_timeout_time_us (uint64_t us)
	Convenience method to get the timestamp a number of microseconds from the current time.
static absolute_time_t	make_timeout_time_ms (uint32_t ms)
	Convenience method to get the timestamp a number of milliseconds from the current time.
static int64_t	absolute_time_diff_us (absolute_time_t from, absolute_time_t to)
	Return the difference in microseconds between two timestamps.
static absolute_time_t	absolute_time_min (absolute_time_t a, absolute_time_t b)
	Return the earlier of two timestamps.
static bool	is_at_the_end_of_time (absolute_time_t t)
	Determine if the given timestamp is "at_the_end_of_time".
static bool	is_nil_time (absolute_time_t t)
	Determine if the given timestamp is nil.
void	sleep_until (absolute_time_t target)
	Wait until after the given timestamp to return.
void	sleep_us (uint64_t us)
	Wait for the given number of microseconds before returning.
void	sleep_ms (uint32_t ms)
	Wait for the given number of milliseconds before returning.
bool	best_effort_wfe_or_timeout (absolute_time_t timeout_timestamp)
	Helper method for blocking on a timeout.
void	alarm_pool_init_default (void)
	Create the default alarm pool (if not already created or disabled).
void	runtime_init_default_alarm_pool (void)
alarm_pool_t *	alarm_pool_get_default (void)
	The default alarm pool used when alarms are added without specifying an alarm pool, and also used by the SDK to support lower power sleeps and timeouts.
alarm_pool_t *	alarm_pool_create_on_timer (alarm_pool_timer_t *timer, uint timer_alarm_num, uint max_timers)
alarm_pool_timer_t *	alarm_pool_timer_for_timer_num (uint timer_num)
alarm_pool_timer_t *	alarm_pool_get_default_timer (void)
static alarm_pool_t *	alarm_pool_create (uint timer_alarm_num, uint max_timers)
	Create an alarm pool.
alarm_pool_t *	alarm_pool_create_on_timer_with_unused_hardware_alarm (alarm_pool_timer_t *timer, uint max_timers)
static alarm_pool_t *	alarm_pool_create_with_unused_hardware_alarm (uint max_timers)
	Create an alarm pool, claiming an used timer_alarm to back it.
uint	alarm_pool_timer_alarm_num (alarm_pool_t *pool)
	Return the timer alarm used by an alarm pool.
static uint	alarm_pool_hardware_alarm_num (alarm_pool_t *pool)
uint	alarm_pool_core_num (alarm_pool_t *pool)
	Return the core number the alarm pool was initialized on (and hence callbacks are called on).
void	alarm_pool_destroy (alarm_pool_t *pool)
	Destroy the alarm pool, cancelling all alarms and freeing up the underlying timer_alarm.
alarm_id_t	alarm_pool_add_alarm_at (alarm_pool_t *pool, absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past)
	Add an alarm callback to be called at a specific time.
alarm_id_t	alarm_pool_add_alarm_at_force_in_context (alarm_pool_t *pool, absolute_time_t time, alarm_callback_t callback, void *user_data)
	Add an alarm callback to be called at or after a specific time.
static alarm_id_t	alarm_pool_add_alarm_in_us (alarm_pool_t *pool, uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past)
	Add an alarm callback to be called after a delay specified in microseconds.
static alarm_id_t	alarm_pool_add_alarm_in_ms (alarm_pool_t *pool, uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past)
	Add an alarm callback to be called after a delay specified in milliseconds.
int64_t	alarm_pool_remaining_alarm_time_us (alarm_pool_t *pool, alarm_id_t alarm_id)
	Return the time remaining before the next trigger of an alarm.
int32_t	alarm_pool_remaining_alarm_time_ms (alarm_pool_t *pool, alarm_id_t alarm_id)
	Return the time remaining before the next trigger of an alarm.
bool	alarm_pool_cancel_alarm (alarm_pool_t *pool, alarm_id_t alarm_id)
	Cancel an alarm.
static alarm_id_t	add_alarm_at (absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past)
	Add an alarm callback to be called at a specific time.
static alarm_id_t	add_alarm_in_us (uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past)
	Add an alarm callback to be called after a delay specified in microseconds.
static alarm_id_t	add_alarm_in_ms (uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past)
	Add an alarm callback to be called after a delay specified in milliseconds.
static bool	cancel_alarm (alarm_id_t alarm_id)
	Cancel an alarm from the default alarm pool.
int64_t	remaining_alarm_time_us (alarm_id_t alarm_id)
	Return the time remaining before the next trigger of an alarm.
int32_t	remaining_alarm_time_ms (alarm_id_t alarm_id)
	Return the time remaining before the next trigger of an alarm.
bool	alarm_pool_add_repeating_timer_us (alarm_pool_t *pool, int64_t delay_us, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
	Add a repeating timer that is called repeatedly at the specified interval in microseconds.
static bool	alarm_pool_add_repeating_timer_ms (alarm_pool_t *pool, int32_t delay_ms, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
	Add a repeating timer that is called repeatedly at the specified interval in milliseconds.
static bool	add_repeating_timer_us (int64_t delay_us, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
	Add a repeating timer that is called repeatedly at the specified interval in microseconds.
static bool	add_repeating_timer_ms (int32_t delay_ms, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
	Add a repeating timer that is called repeatedly at the specified interval in milliseconds.
bool	cancel_repeating_timer (repeating_timer_t *timer)
	Cancel a repeating timer.

Variables
const absolute_time_t	at_the_end_of_time
	The timestamp representing the end of time; this is actually not the maximum possible timestamp, but is set to 0x7fffffff_ffffffff microseconds to avoid sign overflows with time arithmetic. This is almost 300,000 years, so should be sufficient.
const absolute_time_t	nil_time
	The timestamp representing a null timestamp.