gint/include/gint/rtc.h
2021-06-13 18:13:09 +02:00

107 lines
3.4 KiB
C

//---
// gint:rtc - Real-Time Clock
//---
#ifndef GINT_RTC
#define GINT_RTC
#ifdef __cplusplus
extern "C" {
#endif
#include <gint/defs/types.h>
#include <gint/defs/call.h>
#include <gint/timer.h>
//---
// Time management
//---
/* rtc_time_t: A point in time, representable in the RTC registers */
typedef struct
{
uint16_t year; /* Years (exact value, e.g. 2018) */
uint8_t week_day; /* Day of week, (0=Sunday, 6=Saturday) */
uint8_t month; /* Month (0..11) */
uint8_t month_day; /* Day of month (1..31) */
uint8_t hours; /* Hour (0..23) */
uint8_t minutes; /* Minute (0..59) */
uint8_t seconds; /* Second (0..59) */
uint8_t ticks; /* 128-Hz sub-second counter (0...127) */
} rtc_time_t;
/* rtc_get_time(): Read the current time from the RTC
@time Pointer to rtc_time_t structure (needs not be initialized) */
void rtc_get_time(rtc_time_t *time);
/* rtc_set_time(): Set current time in the RTC
If [time->week_day] is not in the valid range, it is set to 0. Other fields
are not checked. R64CNT cannot be set to [time->ticks] is ignored.
@time Pointer to new time */
void rtc_set_time(rtc_time_t const *time);
/* rtc_ticks(): Get number of 128-Hz ticks elapsed since Midnight.
Returns R64CNT + 128*RSECCNT + 128*60*RMINCNT + 128*60*60*RHRCNT. This can
be used as a 128-Hz counter, but it wraps around at midnight. */
uint32_t rtc_ticks(void);
//---
// RTC periodic interrupt
// The real-time clock produces a regular interrupt which may be used as a
// timer with a maximum frequency of 256 Hz. It is also useful to check
// that the clock settings (see <gint/clock.h>) are properly detected, by
// comparing the detected frequencies with the RTC.
//---
/* Possible frequency settings for the RTC's interrupt */
enum
{
RTC_500mHz = 7,
RTC_1Hz = 6,
RTC_2Hz = 5,
RTC_4Hz = 4,
RTC_16Hz = 3,
RTC_64Hz = 2,
RTC_256Hz = 1,
RTC_NONE = 0,
};
/* rtc_periodic_enable(): Enable the periodic interrupt
This function sets up the periodic interrupt to invoke the provided callback
regularly. As with timers, the callback must return either TIMER_CONTINUE or
TIMER_STOP.
Do not confuse this interrupt with CASIO's extra timers that run at 32768 Hz
(which are called "RTC timers" in CPU73050.dll). These timers are called
Extra TMU or ETMU in gint and are handled by <gint/timer.h>.
Note that the timing of the first callback is always uncertain. A 1 Hz timer
set up when half of the current second is already elapsed will be called for
the first time after only 500 ms, for instance.
@frequency Periodic interrupt frequency
@callback Function to call back at the specified frequency
Returns true on success, false if the interrupt is already in use. */
bool rtc_periodic_enable(int frequency, gint_call_t callback);
/* rtc_periodic_disable(): Stop the periodic interrupt
This has the same effect as returning TIMER_STOP from the callback, or
setting RTC_NONE as the parameter for rtc_periodic_enable(). */
void rtc_periodic_disable(void);
/* Deprecated versions with old-style callbacks and more confusing names */
__attribute__((deprecated("Use rtc_periodic_enable() instead")))
int rtc_start_timer(int frequency, timer_callback_t callback, ...);
#define rtc_start_timer(...) rtc_start_timer(__VA_ARGS__, 0)
__attribute__((deprecated("Use rtc_periodic_disable() instead")))
void rtc_stop_timer(void);
#ifdef __cplusplus
}
#endif
#endif /* GINT_RTC */