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/*
* MIT License
*
* Copyright (c) 2020 Joey Castillo
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef _WATCH_RTC_H_INCLUDED
#define _WATCH_RTC_H_INCLUDED
////< @file watch_rtc.h
#include "watch.h"
#include "hpl_calendar.h"
/** @addtogroup rtc Real-Time Clock
* @brief This section covers functions related to the SAM L22's real-time clock peripheral, including
* date, time and alarm functions.
* @details The real-time clock is the only peripheral that main.c enables for you. It is the cornerstone
* of low power operation on the watch, and it is required for several key functions that we
* assume will be available, namely the wake from BACKUP mode and the callback on the ALARM button.
* It is also required for the operation of the 1 Hz tick interrupt, which you will most likely use
* to wake from STANDBY mode.
*/
/// @{
#define WATCH_RTC_REFERENCE_YEAR (2020)
typedef union {
struct {
uint32_t second : 6; // 0-59
uint32_t minute : 6; // 0-59
uint32_t hour : 5; // 0-23
uint32_t day : 5; // 1-31
uint32_t month : 4; // 1-12
uint32_t year : 6; // 0-63 (representing 2020-2083)
} unit;
uint32_t reg; // the bit-packed value as expected by the RTC peripheral's CLOCK register.
} watch_date_time;
typedef enum watch_rtc_alarm_match {
ALARM_MATCH_DISABLED = 0,
ALARM_MATCH_SS,
ALARM_MATCH_MMSS,
ALARM_MATCH_HHMMSS,
} watch_rtc_alarm_match;
/** @brief Called by main.c to check if the RTC is enabled.
* You may call this function, but outside of app_init, it should always return true.
*/
bool _watch_rtc_is_enabled(void);
/** @brief Sets the date and time.
* @param date_time The date and time you wish to set, with a year value from 0-63 representing 2020-2083.
* @note The SAM L22 stores the year as six bits representing a value from 0 to 63. It treats this as a year
* offset from a reference year, which must be a leap year. Since 2020 was a leap year, and it allows
* useful dates through 2083, it is assumed that watch apps will use 2020 as the reference year; thus
* 1 means 2021, 2 means 2022, etc. **You will be responsible for handling this offset in your code**,
* if the calendar year is needed for timestamp calculation logic or display purposes.
*/
void watch_rtc_set_date_time(watch_date_time date_time);
/** @brief Returns the date and time.
* @return A watch_date_time with the current date and time, with a year value from 0-63 representing 2020-2083.
* @see watch_rtc_set_date_time for notes about how the year is stored.
*/
watch_date_time watch_rtc_get_date_time(void);
/** @brief Registers an alarm callback that will be called when the RTC time matches the target time, as masked
* by the provided mask.
* @param callback The function you wish to have called when the alarm fires. If this value is NULL, the alarm
* interrupt will still be enabled, but no callback function will be called.
* @param alarm_time The time that you wish to match. The date is currently ignored.
* @param mask One of the values in watch_rtc_alarm_match indicating which values to check.
* @details The alarm interrupt is a versatile tool for scheduling events in the future, especially since it can
* wake the device from all sleep modes. The key to its versatility is the mask parameter.
* Suppose we set an alarm for midnight, 00:00:00.
* * if mask is ALARM_MATCH_SS, the alarm will fire every minute when the clock ticks to seconds == 0.
* * with ALARM_MATCH_MMSS, the alarm will once an hour, at the top of each hour.
* * with ALARM_MATCH_HHMMSS, the alarm will fire at midnight every day.
* In theory the SAM L22's alarm function can match on days, months and even years, but I have not had
* success with this yet; as such, I am omitting these options for now.
*/
void watch_rtc_register_alarm_callback(ext_irq_cb_t callback, watch_date_time alarm_time, watch_rtc_alarm_match mask);
/** @brief Disables the alarm callback.
*/
void watch_rtc_disable_alarm_callback(void);
/** @brief Registers a "tick" callback that will be called once per second.
* @param callback The function you wish to have called when the clock ticks. If you pass in NULL, the tick
* interrupt will still be enabled, but no callback function will be called.
* @note this is equivalent to calling watch_rtc_register_periodic_callback with a frequency of 1. It can be
* disabled with either watch_rtc_disable_tick_callback() or watch_rtc_disable_periodic_callback(1),
* and will also be disabled when watch_rtc_disable_all_periodic_callbacks is called.
*/
void watch_rtc_register_tick_callback(ext_irq_cb_t callback);
/** @brief Disables the tick callback for the given period.
*/
void watch_rtc_disable_tick_callback(void);
/** @brief Registers a callback that will be called at a configurable period.
* @param callback The function you wish to have called at the specified period. If you pass in NULL, the periodic
* interrupt will still be enabled, but no callback function will be called.
* @param frequency The frequency of the tick in Hz. **Must be a power of 2**, from 1 to 128 inclusive.
* @note A 1 Hz tick (@see watch_rtc_register_tick_callback) is suitable for most applications, in that it gives you a
* chance to update the display once a second — an ideal update rate for a watch! If however you are displaying
* a value (such as an accelerometer output) that updates more frequently than once per second, you may want to
* tick at 16 or 32 Hz to update the screen more quickly. Just remember that the more frequent the tick, the more
* power your app will consume. Ideally you should enable the fast tick only when the user requires it (i.e. in
* response to an input event), and move back to the slow tick after some time.
*
* Also note that the RTC peripheral does not have sub-second resolution, so even if you set a 2 or 4 Hz interval,
* the system will not have any way of telling you where you are within a given second; watch_rtc_get_date_time
* will return the exact same timestamp until the second ticks over.
*/
void watch_rtc_register_periodic_callback(ext_irq_cb_t callback, uint8_t frequency);
/** @brief Disables the tick callback for the given period.
* @param frequency The frequency of the tick you wish to disable, in Hz. **Must be a power of 2**, from 1 to 128.
*/
void watch_rtc_disable_periodic_callback(uint8_t frequency);
/** @brief Disables tick callbacks for the given periods (as a bitmask).
* @param mask The frequencies of tick callbacks you wish to disable, in Hz.
* The 128 Hz callback is 0b1, the 64 Hz callback is 0b10, the 32 Hz callback is 0b100, etc.
*/
void watch_rtc_disable_matching_periodic_callbacks(uint8_t mask);
/** @brief Disables all periodic callbacks, including the once-per-second tick callback.
*/
void watch_rtc_disable_all_periodic_callbacks(void);
/// @}
#endif
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