Merge pull request #16 from joeycastillo/rtc-refactor

Refactor Real-Time Clock Functionality

35 files changed, 422 insertions, 1771 deletions

diff --git a/apps/Sensor Watch BME280 Project/app.c b/apps/Sensor Watch BME280 Project/app.c
index e07b35f8..366ccde9 100644
--- a/apps/Sensor Watch BME280 Project/app.c
+++ b/apps/Sensor Watch BME280 Project/app.c
@@ -21,13 +21,6 @@ void app_wake_from_deep_sleep() {
 }
 
 void app_setup() {
-    struct calendar_date_time date_time;
-    watch_get_date_time(&date_time);
-    if (date_time.date.year < 2020) {
-        date_time.date.year = 2020;
-        watch_set_date_time(date_time);
-    }
-
     watch_enable_external_interrupts();
     watch_register_interrupt_callback(BTN_MODE, cb_mode_pressed, INTERRUPT_TRIGGER_RISING);
     watch_register_interrupt_callback(BTN_LIGHT, cb_light_pressed, INTERRUPT_TRIGGER_RISING);
@@ -64,7 +57,7 @@ void app_setup() {
 
     watch_enable_display();
 
-    watch_register_tick_callback(cb_tick);
+    watch_rtc_register_tick_callback(cb_tick);
 }
 
 /**
@@ -191,9 +184,8 @@ float read_humidity(int32_t t_fine) {
 }
 
 void log_data() {
-    struct calendar_date_time date_time;
-    watch_get_date_time(&date_time);
-    uint8_t hour = date_time.time.hour;
+    watch_date_time date_time = watch_rtc_get_date_time();
+    uint8_t hour = date_time.unit.hour;
     int8_t temperature = read_temperature(NULL);
 
     for(int i = 0; i < MAX_DATA_POINTS - 1; i++) {
@@ -205,12 +197,11 @@ void log_data() {
 }
 
 void do_clock_mode() {
-    struct calendar_date_time date_time;
+    watch_date_time date_time = watch_rtc_get_date_time();
     const char months[12][3] = {"JA", "FE", "MR", "AR", "MA", "JN", "JL", "AU", "SE", "OC", "NO", "dE"};
 
-    watch_get_date_time(&date_time);
-    watch_display_string((char *)months[date_time.date.month - 1], 0);
-    sprintf(buf, "%2d%2d%02d%02d", date_time.date.day, date_time.time.hour, date_time.time.min, date_time.time.sec);
+    watch_display_string((char *)months[date_time.unit.month - 1], 0);
+    sprintf(buf, "%2d%2d%02d%02d", date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second);
     watch_display_string(buf, 2);
     watch_set_colon();
 }
@@ -271,28 +262,27 @@ void prefs_mode_handle_secondary_button() {
 }
 
 void do_set_time_mode() {
-    struct calendar_date_time date_time;
+    watch_date_time date_time = watch_rtc_get_date_time();
 
-    watch_get_date_time(&date_time);
     watch_display_string("          ", 0);
     switch (application_state.page) {
         case 0: // hour
-            sprintf(buf, "ST t%2d", date_time.time.hour);
+            sprintf(buf, "ST t%2d", date_time.unit.hour);
             break;
         case 1: // minute
-            sprintf(buf, "ST t  %02d", date_time.time.min);
+            sprintf(buf, "ST t  %02d", date_time.unit.minute);
             break;
         case 2: // second
-            sprintf(buf, "ST t    %02d", date_time.time.sec);
+            sprintf(buf, "ST t    %02d", date_time.unit.second);
             break;
         case 3: // year
-            sprintf(buf, "ST d%2d", date_time.date.year - 2000);
+            sprintf(buf, "ST d%2d", date_time.unit.year + 20);
             break;
         case 4: // month
-            sprintf(buf, "ST d  %02d", date_time.date.month);
+            sprintf(buf, "ST d  %02d", date_time.unit.month);
             break;
         case 5: // day
-            sprintf(buf, "ST d    %02d", date_time.date.day);
+            sprintf(buf, "ST d    %02d", date_time.unit.day);
             break;
     }
     watch_display_string(buf, 0);
@@ -305,37 +295,36 @@ void set_time_mode_handle_primary_button() {
 }
 
 void set_time_mode_handle_secondary_button() {
-    struct calendar_date_time date_time;
-    watch_get_date_time(&date_time);
+    watch_date_time date_time = watch_rtc_get_date_time();
     const uint8_t days_in_month[12] = {31, 28, 31, 30, 31, 30, 30, 31, 30, 31, 30, 31};
 
     switch (application_state.page) {
         case 0: // hour
-            date_time.time.hour = (date_time.time.hour + 1) % 24;
+            date_time.unit.hour = (date_time.unit.hour + 1) % 24;
             break;
         case 1: // minute
-            date_time.time.min = (date_time.time.min + 1) % 60;
+            date_time.unit.minute = (date_time.unit.minute + 1) % 60;
             break;
         case 2: // second
-            date_time.time.sec = 0;
+            date_time.unit.second = 0;
             break;
         case 3: // year
             // only allow 2021-2030. fix this sometime next decade
-            date_time.date.year = ((date_time.date.year % 10) + 1) + 2020;
+            date_time.unit.year = ((date_time.unit.year % 10) + 1);
             break;
         case 4: // month
-            date_time.date.month = ((date_time.date.month + 1) % 12);
+            date_time.unit.month = ((date_time.unit.month + 1) % 12);
             break;
         case 5: // day
-            date_time.date.day = date_time.date.day + 1;
+            date_time.unit.day = date_time.unit.day + 1;
             // can't set to the 29th on a leap year. if it's february 29, set to 11:59 on the 28th.
             // and it should roll over.
-            if (date_time.date.day > days_in_month[date_time.date.month - 1]) {
-                date_time.date.day = 1;
+            if (date_time.unit.day > days_in_month[date_time.unit.month - 1]) {
+                date_time.unit.day = 1;
             }
             break;
     }
-    watch_set_date_time(date_time);
+    watch_rtc_set_date_time(date_time);
 }
 
 void cb_mode_pressed() {
@@ -377,9 +366,8 @@ void cb_alarm_pressed() {
 
 void cb_tick() {
     // TODO: use alarm interrupt to trigger data acquisition.
-    struct calendar_date_time date_time;
-    watch_get_date_time(&date_time);
-    if (date_time.time.min == 0 && date_time.time.sec == 0) {
+    watch_date_time date_time = watch_rtc_get_date_time();
+    if (date_time.unit.minute == 0 && date_time.unit.second == 0) {
         log_data();
     }
 
diff --git a/apps/beats-time/app.c b/apps/beats-time/app.c
index c694bc5e..47d0add2 100644
--- a/apps/beats-time/app.c
+++ b/apps/beats-time/app.c
@@ -51,13 +51,6 @@ void app_wake_from_deep_sleep() {
 }
 
 void app_setup() {
-    struct calendar_date_time date_time;
-    watch_get_date_time(&date_time);
-    if (date_time.date.year < 2020) {
-        date_time.date.year = 2020;
-        watch_set_date_time(date_time);
-    }
-
     watch_enable_external_interrupts();
     watch_register_interrupt_callback(BTN_MODE, cb_mode_pressed, INTERRUPT_TRIGGER_RISING);
     watch_register_interrupt_callback(BTN_LIGHT, cb_light_pressed, INTERRUPT_TRIGGER_RISING);
@@ -67,7 +60,7 @@ void app_setup() {
     watch_enable_leds();
     watch_enable_display();
 
-    watch_register_tick_callback(cb_tick);
+    watch_rtc_register_tick_callback(cb_tick);
 }
 
 void app_prepare_for_sleep() {
@@ -128,24 +121,21 @@ bool app_loop() {
 }
 
 void do_clock_mode() {
-    struct calendar_date_time date_time;
+    watch_date_time date_time = watch_rtc_get_date_time();
     const char months[12][3] = {"JA", "FE", "MR", "AR", "MA", "JN", "JL", "AU", "SE", "OC", "NO", "dE"};
 
-    watch_get_date_time(&date_time);
-    watch_display_string((char *)months[date_time.date.month - 1], 0);
-    sprintf(buf, "%2d%2d%02d%02d", date_time.date.day, date_time.time.hour, date_time.time.min, date_time.time.sec);
+    watch_display_string((char *)months[date_time.unit.month - 1], 0);
+    sprintf(buf, "%2d%2d%02d%02d", date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second);
     watch_display_string(buf, 2);
     watch_set_colon();
+
 }
 
 void do_beats_mode() {
     watch_clear_colon();
 
-    struct calendar_date_time date_time;
-
-    watch_get_date_time(&date_time);
-
-    uint16_t beats = clock2beats(date_time.time.hour, date_time.time.min, date_time.time.sec, UTC_OFFSET);
+    watch_date_time date_time = watch_rtc_get_date_time();
+    uint16_t beats = clock2beats(date_time.unit.hour, date_time.unit.minute, date_time.unit.second, UTC_OFFSET);
     sprintf(buf, "bt  %04d  ", beats);
 
     watch_display_string(buf, 0);
@@ -164,28 +154,27 @@ uint16_t clock2beats(uint16_t hours, uint16_t minutes, uint16_t seconds, int16_t
 }
 
 void do_set_time_mode() {
-    struct calendar_date_time date_time;
+    watch_date_time date_time = watch_rtc_get_date_time();
 
-    watch_get_date_time(&date_time);
     watch_display_string("          ", 0);
     switch (application_state.page) {
         case 0: // hour
-            sprintf(buf, "ST t%2d", date_time.time.hour);
+            sprintf(buf, "ST t%2d", date_time.unit.hour);
             break;
         case 1: // minute
-            sprintf(buf, "ST t  %02d", date_time.time.min);
+            sprintf(buf, "ST t  %02d", date_time.unit.minute);
             break;
         case 2: // second
-            sprintf(buf, "ST t    %02d", date_time.time.sec);
+            sprintf(buf, "ST t    %02d", date_time.unit.second);
             break;
         case 3: // year
-            sprintf(buf, "ST d%2d", date_time.date.year - 2000);
+            sprintf(buf, "ST d%2d", date_time.unit.year + 20);
             break;
         case 4: // month
-            sprintf(buf, "ST d  %02d", date_time.date.month);
+            sprintf(buf, "ST d  %02d", date_time.unit.month);
             break;
         case 5: // day
-            sprintf(buf, "ST d    %02d", date_time.date.day);
+            sprintf(buf, "ST d    %02d", date_time.unit.day);
             break;
     }
     watch_display_string(buf, 0);
@@ -198,37 +187,36 @@ void set_time_mode_handle_primary_button() {
 }
 
 void set_time_mode_handle_secondary_button() {
-    struct calendar_date_time date_time;
-    watch_get_date_time(&date_time);
+    watch_date_time date_time = watch_rtc_get_date_time();
     const uint8_t days_in_month[12] = {31, 28, 31, 30, 31, 30, 30, 31, 30, 31, 30, 31};
 
     switch (application_state.page) {
         case 0: // hour
-            date_time.time.hour = (date_time.time.hour + 1) % 24;
+            date_time.unit.hour = (date_time.unit.hour + 1) % 24;
             break;
         case 1: // minute
-            date_time.time.min = (date_time.time.min + 1) % 60;
+            date_time.unit.minute = (date_time.unit.minute + 1) % 60;
             break;
         case 2: // second
-            date_time.time.sec = 0;
+            date_time.unit.second = 0;
             break;
         case 3: // year
             // only allow 2021-2030. fix this sometime next decade
-            date_time.date.year = ((date_time.date.year % 10) + 1) + 2020;
+            date_time.unit.year = ((date_time.unit.year % 10) + 1);
             break;
         case 4: // month
-            date_time.date.month = ((date_time.date.month + 1) % 12);
+            date_time.unit.month = ((date_time.unit.month + 1) % 12);
             break;
         case 5: // day
-            date_time.date.day = date_time.date.day + 1;
+            date_time.unit.day = date_time.unit.day + 1;
             // can't set to the 29th on a leap year. if it's february 29, set to 11:59 on the 28th.
             // and it should roll over.
-            if (date_time.date.day > days_in_month[date_time.date.month - 1]) {
-                date_time.date.day = 1;
+            if (date_time.unit.day > days_in_month[date_time.unit.month - 1]) {
+                date_time.unit.day = 1;
             }
             break;
     }
-    watch_set_date_time(date_time);
+    watch_rtc_set_date_time(date_time);
 }
 
 void cb_mode_pressed() {
diff --git a/make.mk b/make.mk
index 461bef79..299d9d31 100644
--- a/make.mk
+++ b/make.mk
@@ -31,8 +31,6 @@ LDFLAGS += -mcpu=cortex-m0plus -mthumb
 LDFLAGS += -Wl,--gc-sections
 LDFLAGS += -Wl,--script=$(TOP)//watch-library/linker/saml22j18.ld
 
-# If you add any additional directories with headers, add them to this list, e.g.
-# ../drivers/
 INCLUDES += \
   -I$(TOP)/tinyusb/src \
   -I$(TOP)/boards/$(BOARD) \
@@ -54,7 +52,6 @@ INCLUDES += \
   -I$(TOP)/watch-library/hpl/oscctrl/ \
   -I$(TOP)/watch-library/hpl/pm/ \
   -I$(TOP)/watch-library/hpl/port/ \
-  -I$(TOP)/watch-library/hpl/rtc/ \
   -I$(TOP)/watch-library/hpl/sercom/ \
   -I$(TOP)/watch-library/hpl/slcd/ \
   -I$(TOP)/watch-library/hpl/systick/ \
@@ -64,8 +61,6 @@ INCLUDES += \
   -I$(TOP)/watch-library/watch/ \
   -I$(TOP)/watch-library
 
-# If you add any additional C files to your project, add them each to this list, e.g.
-# ../drivers/st25dv.c
 SRCS += \
   $(TOP)/tinyusb/src/tusb.c \
   $(TOP)/tinyusb/src/common/tusb_fifo.c \
@@ -76,9 +71,19 @@ SRCS += \
   $(TOP)/watch-library/main.c \
   $(TOP)/watch-library/startup_saml22.c \
   $(TOP)/watch-library/hw/driver_init.c \
+  $(TOP)/watch-library/watch/watch_rtc.c \
+  $(TOP)/watch-library/watch/watch_slcd.c \
+  $(TOP)/watch-library/watch/watch_extint.c \
+  $(TOP)/watch-library/watch/watch_led.c \
+  $(TOP)/watch-library/watch/watch_buzzer.c \
+  $(TOP)/watch-library/watch/watch_adc.c \
+  $(TOP)/watch-library/watch/watch_gpio.c \
+  $(TOP)/watch-library/watch/watch_i2c.c \
+  $(TOP)/watch-library/watch/watch_uart.c \
+  $(TOP)/watch-library/watch/watch_deepsleep.c \
+  $(TOP)/watch-library/watch/watch_private.c \
   $(TOP)/watch-library/watch/watch.c \
   $(TOP)/watch-library/hal/src/hal_atomic.c \
-  $(TOP)/watch-library/hal/src/hal_calendar.c \
   $(TOP)/watch-library/hal/src/hal_delay.c \
   $(TOP)/watch-library/hal/src/hal_ext_irq.c \
   $(TOP)/watch-library/hal/src/hal_gpio.c \
@@ -100,7 +105,6 @@ SRCS += \
   $(TOP)/watch-library/hpl/osc32kctrl/hpl_osc32kctrl.c \
   $(TOP)/watch-library/hpl/oscctrl/hpl_oscctrl.c \
   $(TOP)/watch-library/hpl/pm/hpl_pm.c \
-  $(TOP)/watch-library/hpl/rtc/hpl_rtc.c \
   $(TOP)/watch-library/hpl/sercom/hpl_sercom.c \
   $(TOP)/watch-library/hpl/slcd/hpl_slcd.c \
   $(TOP)/watch-library/hpl/systick/hpl_systick.c \
diff --git a/watch-library/hal/documentation/calendar.rst b/watch-library/hal/documentation/calendar.rst
deleted file mode 100644
index 8a3de6e8..00000000
--- a/watch-library/hal/documentation/calendar.rst
+++ /dev/null
@@ -1,72 +0,0 @@
-===============================
-The Calendar driver (bare-bone)
-===============================
-
-The Calendar driver provides means to set and get current date and time.
-After enabling, an instance of the driver starts counting time from the base date with
-the resolution of one second. The default base date is 00:00:00 1st of January 1970.
-Only the base year of the base date can be changed via the driver API.
-
-The current date and time is kept internally in a relative form as the difference between
-current date and time and the base date and time. This means that changing the base year changes
-current date.
-
-The base date and time defines time "zero" or the earliest possible point in time that the calender driver can describe,
-this means that current time and alarms can not be set to anything earlier than this time.
-
-The Calendar driver provides alarm functionality.
-An alarm is a software trigger which fires on particular date and time with particular periodicity.
-Upon firing the given callback function is called.
-
-An alarm can be in single-shot mode, firing only once at matching time; or in repeating mode, meaning that it will
-reschedule a new alarm automatically based on repeating mode configuration.
-In single-shot mode an alarm is removed from the alarm queue before its callback is called. It allows an application to
-reuse the memory of expired alarm in the callback.
-
-An alarm can be triggered on the following events: match on second, minute, hour, day, month or year.
-Matching on second means that the alarm is triggered when the value of seconds of the current time is equal to
-the alarm's value of seconds. This means repeating alarm with match on seconds is triggered with the period of a minute.
-Matching on minute means that the calendars minute and seconds values has to match the alarms, the rest of the date-time
-value is ignored. In repeating mode this means a new alarm every hour.
-The same logic is applied to match on hour, day, month and year.
-
-Each instance of the Calendar driver supports infinite amount of software alarms, only limited by the amount of RAM available.
-
-Features
---------
-* Initialization and de-initialization
-* Enabling and disabling
-* Date and time operations
-* Software alarms
-
-Applications
-------------
-* A source of current date and time for an embedded system.
-* Periodical functionality in low-power applications since the driver is designed to use 1Hz clock.
-* Periodical function calls in case if it is more convenient to operate with absolute time.
-
-Dependencies
-------------
-* This driver expects a counter to be increased by one every second to count date and time correctly.
-* Each instance of the driver requires separate hardware timer.
-
-Concurrency
------------
-The Calendar driver is an interrupt driven driver.This means that the interrupt that triggers an alarm may occur during
-the process of adding or removing an alarm via the driver's API. In such case the interrupt processing is postponed
-until the alarm adding or removing is complete.
-
-The alarm queue is not protected from the access by interrupts not used by the driver. Due to this
-it is not recommended to add or remove an alarm from such interrupts: in case if a higher priority interrupt supersedes
-the driver's interrupt, adding or removing an alarm may cause unpredictable behavior of the driver.
-
-Limitations
------------
-* Only years divisible by 4 are deemed a leap year, this gives a correct result between the years 1901 to 2099.
-* The driver is designed to work outside of an operating system environment, the software alarm queue is therefore processed in interrupt context which may delay execution of other interrupts.
-* If there are a lot of frequently called interrupts with the priority higher than the driver's one, it may cause delay in alarm's triggering.
-* Changing the base year or setting current date or time does not shift alarms' date and time accordingly or expires alarms.
-
-Knows issues and workarounds
-----------------------------
-Not applicable
diff --git a/watch-library/hal/include/hal_calendar.h b/watch-library/hal/include/hal_calendar.h
index 26949a57..e69de29b 100644
--- a/watch-library/hal/include/hal_calendar.h
+++ b/watch-library/hal/include/hal_calendar.h
@@ -1,159 +0,0 @@
-/**
- * \file
- *
- * \brief Generic CALENDAR functionality declaration.
- *
- * Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.
- *
- * \asf_license_start
- *
- * \page License
- *
- * Subject to your compliance with these terms, you may use Microchip
- * software and any derivatives exclusively with Microchip products.
- * It is your responsibility to comply with third party license terms applicable
- * to your use of third party software (including open source software) that
- * may accompany Microchip software.
- *
- * THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES,
- * WHETHER EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE,
- * INCLUDING ANY IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY,
- * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL MICROCHIP BE
- * LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE, INCIDENTAL OR CONSEQUENTIAL
- * LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND WHATSOEVER RELATED TO THE
- * SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS BEEN ADVISED OF THE
- * POSSIBILITY OR THE DAMAGES ARE FORESEEABLE.  TO THE FULLEST EXTENT
- * ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY
- * RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
- * THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.
- *
- * \asf_license_stop
- *
- */
-
-#ifndef _HAL_CALENDER_H_INCLUDED
-#define _HAL_CALENDER_H_INCLUDED
-
-#include "hpl_calendar.h"
-#include <utils_list.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
- * \addtogroup doc_driver_hal_calendar_async
- *
- *@{
- */
-
-/** \brief Prototype of callback on alarm match
- *  \param calendar Pointer to the HAL Calendar instance.
- */
-typedef void (*calendar_cb_alarm_t)(struct calendar_descriptor *const calendar);
-
-/** \brief Struct for alarm time
- */
-struct calendar_alarm {
-	struct list_element    elem;
-	struct _calendar_alarm cal_alarm;
-	calendar_cb_alarm_t    callback;
-};
-
-/** \brief Initialize the Calendar HAL instance and hardware
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \param hw       Pointer to the hardware instance.
- *  \return Operation status of init
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_init(struct calendar_descriptor *const calendar, const void *hw);
-
-/** \brief Reset the Calendar HAL instance and hardware
- *
- *  Reset Calendar instance to hardware defaults.
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \return Operation status of reset.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_deinit(struct calendar_descriptor *const calendar);
-
-/** \brief Enable the Calendar HAL instance and hardware
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \return Operation status of init
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_enable(struct calendar_descriptor *const calendar);
-
-/** \brief Disable the Calendar HAL instance and hardware
- *
- *  Disable Calendar instance to hardware defaults.
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \return Operation status of reset.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_disable(struct calendar_descriptor *const calendar);
-
-/** \brief Configure the base year for calendar HAL instance and hardware
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \param p_base_year The desired base year.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_set_baseyear(struct calendar_descriptor *const calendar, const uint32_t p_base_year);
-
-/** \brief Configure the time for calendar HAL instance and hardware
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \param p_calendar_time Pointer to the time configuration.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_set_time(struct calendar_descriptor *const calendar, struct calendar_time *const p_calendar_time);
-
-/** \brief Configure the date for calendar HAL instance and hardware
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \param p_calendar_date Pointer to the date configuration.
- *  \return Operation status of time set.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_set_date(struct calendar_descriptor *const calendar, struct calendar_date *const p_calendar_date);
-
-/** \brief Get the time for calendar HAL instance and hardware
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \param date_time Pointer to the value that will be filled with the current time.
- *  \return Operation status of time retrieve.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_get_date_time(struct calendar_descriptor *const calendar, struct calendar_date_time *const date_time);
-
-/** \brief Config the alarm time for calendar HAL instance and hardware
- *
- *  Set the alarm time to calendar instance. If the callback is NULL, remove
- *  the alarm if the alarm is already added, otherwise, ignore the alarm.
- *
- *  \param calendar Pointer to the HAL Calendar instance.
- *  \param alarm Pointer to the configuration.
- *  \param callback Pointer to the callback function.
- *  \return Operation status of alarm time set.
- *  \retval 0       Completed successfully.
- */
-int32_t calendar_set_alarm(struct calendar_descriptor *const calendar, struct calendar_alarm *const alarm,
-                           calendar_cb_alarm_t callback);
-
-/** \brief Retrieve the current driver version
- *  \return Current driver version.
- */
-uint32_t calendar_get_version(void);
-
-/**@}*/
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _HAL_CALENDER_H_INCLUDED */
diff --git a/watch-library/hal/include/hpl_calendar.h b/watch-library/hal/include/hpl_calendar.h
index f94249b9..0dce40fd 100644
--- a/watch-library/hal/include/hpl_calendar.h
+++ b/watch-library/hal/include/hpl_calendar.h
@@ -33,69 +33,11 @@
 #ifndef _HPL_CALENDER_H_INCLUDED
 #define _HPL_CALENDER_H_INCLUDED
 
-#include <compiler.h>
-#include <utils_list.h>
-#include "hpl_irq.h"
-
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /**
- * \brief Calendar structure
- *
- * The Calendar structure forward declaration.
- */
-struct calendar_dev;
-
-/**
- * \brief Available mask options for alarms.
- *
- * Available mask options for alarms.
- */
-enum calendar_alarm_option {
-	/** Alarm disabled. */
-	CALENDAR_ALARM_MATCH_DISABLED = 0,
-	/** Alarm match on second. */
-	CALENDAR_ALARM_MATCH_SEC,
-	/** Alarm match on second and minute. */
-	CALENDAR_ALARM_MATCH_MIN,
-	/** Alarm match on second, minute, and hour. */
-	CALENDAR_ALARM_MATCH_HOUR,
-	/** Alarm match on second, minute, hour, and day. */
-	CALENDAR_ALARM_MATCH_DAY,
-	/** Alarm match on second, minute, hour, day, and month. */
-	CALENDAR_ALARM_MATCH_MONTH,
-	/** Alarm match on second, minute, hour, day, month and year. */
-	CALENDAR_ALARM_MATCH_YEAR
-};
-
-/**
- * \brief Available mode for alarms.
- */
-enum calendar_alarm_mode { ONESHOT = 1, REPEAT };
-/**
- * \brief Prototype of callback on alarm match
- */
-typedef void (*calendar_drv_cb_t)();
-typedef void (*calendar_drv_extwake_cb_t)(uint8_t reason);
-
-/**
- * \brief Structure of Calendar instance
- */
-struct calendar_dev {
-	/** Pointer to the hardware base */
-	void *hw;
-	/** Alarm match callback */
-	calendar_drv_cb_t callback_alarm;
-	/** Tamper callback */
-	calendar_drv_extwake_cb_t callback_tamper;
-	/** Tick callback */
-	calendar_drv_cb_t callback_tick;
-	/** IRQ struct */
-	struct _irq_descriptor irq;
-};
-/**
  * \brief Time struct for calendar
  */
 struct calendar_time {
@@ -119,17 +61,6 @@ struct calendar_date {
 	uint16_t year;
 };
 
-/** \brief Calendar driver struct
- *
- */
-struct calendar_descriptor {
-	struct calendar_dev    device;
-	struct list_descriptor alarms;
-	/*base date/time = base_year/1/1/0/0/0(year/month/day/hour/min/sec)*/
-	uint32_t base_year;
-	uint8_t  flags;
-};
-
 /** \brief Date&Time struct for calendar
  */
 struct calendar_date_time {
@@ -137,188 +68,6 @@ struct calendar_date_time {
 	struct calendar_date date;
 };
 
-/** \brief struct for alarm time
- */
-struct _calendar_alarm {
-	struct calendar_date_time  datetime;
-	uint32_t                   timestamp;
-	enum calendar_alarm_option option;
-	enum calendar_alarm_mode   mode;
-};
-
-/** \enum for tamper detection mode
- */
-enum tamper_detection_mode { TAMPER_MODE_OFF = 0U, TAMPER_MODE_WAKE, TAMPER_MODE_CAPTURE, TAMPER_MODE_ACTL };
-
-/** \enum for tamper detection mode
- */
-enum tamper_id { TAMPID0 = 0U, TAMPID1, TAMPID2, TAMPID3, TAMPID4 };
-/**
- * \brief Initialize Calendar instance
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_init(struct calendar_dev *const dev);
-
-/**
- * \brief Deinitialize Calendar instance
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_deinit(struct calendar_dev *const dev);
-
-/**
- * \brief Enable Calendar instance
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_enable(struct calendar_dev *const dev);
-
-/**
- * \brief Disable Calendar instance
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_disable(struct calendar_dev *const dev);
-/**
- * \brief Set counter for calendar
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] counter The counter for set
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_set_counter(struct calendar_dev *const dev, const uint32_t counter);
-
-/**
- * \brief Get counter for calendar
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return return current counter value
- */
-uint32_t _calendar_get_counter(struct calendar_dev *const dev);
-
-/**
- * \brief Set compare value for calendar
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] comp The compare value for set
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_set_comp(struct calendar_dev *const dev, const uint32_t comp);
-
-/**
- * \brief Get compare value for calendar
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return return current compare value
- */
-uint32_t _calendar_get_comp(struct calendar_dev *const dev);
-
-/**
- * \brief Register callback for calendar alarm
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] callback The pointer to callback function
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _calendar_register_callback(struct calendar_dev *const dev, calendar_drv_cb_t callback);
-
-/**
- * \brief Set calendar IRQ
- *
- * \param[in] dev The pointer to calendar device struct
- */
-void _calendar_set_irq(struct calendar_dev *const dev);
-
-/**
- * \brief Register callback for 1Hz tick from prescaler
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] callback The pointer to callback function
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _prescaler_register_callback(struct calendar_dev *const dev, calendar_drv_cb_t callback);
-
-/**
- * \brief Register callback for tamper detection
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] callback The pointer to callback function
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _extwake_register_callback(struct calendar_dev *const dev, calendar_drv_extwake_cb_t callback);
-
-/**
- * \brief Find tamper is detected on specified pin
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] enum Tamper ID number
- *
- * \return true on detection success and false on failure.
- */
-bool _is_tamper_detected(struct calendar_dev *const dev, enum tamper_id tamper_id_pin);
-
-/**
- * \brief brief Clear the Tamper ID flag
- *
- * \param[in] dev The pointer to calendar device struct
- * \param[in] enum Tamper ID number
- *
- * \return ERR_NONE
- */
-int32_t _tamper_clear_tampid_flag(struct calendar_dev *const dev, enum tamper_id tamper_id_pin);
-
-/**
- * \brief Enable Debounce Asynchronous Feature
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _tamper_enable_debounce_asynchronous(struct calendar_dev *const dev);
-
-/**
- * \brief Disable Tamper Debounce Asynchronous Feature
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _tamper_disable_debounce_asynchronous(struct calendar_dev *const dev);
-
-/**
- * \brief Enable Tamper Debounce Majority Feature
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _tamper_enable_debounce_majority(struct calendar_dev *const dev);
-
-/**
- * \brief Enable Tamper Debounce Majority Feature
- *
- * \param[in] dev The pointer to calendar device struct
- *
- * \return ERR_NONE on success, or an error code on failure.
- */
-int32_t _tamper_disable_debounce_majority(struct calendar_dev *const dev);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/watch-library/hal/src/hal_calendar.c b/watch-library/hal/src/hal_calendar.c
index 68cb7286..e69de29b 100644
--- a/watch-library/hal/src/hal_calendar.c
+++ b/watch-library/hal/src/hal_calendar.c
@@ -1,645 +0,0 @@
-/**
- * \file
- *
- * \brief Generic CALENDAR functionality implementation.
- *
- * Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.
- *
- * \asf_license_start
- *
- * \page License
- *
- * Subject to your compliance with these terms, you may use Microchip
- * software and any derivatives exclusively with Microchip products.
- * It is your responsibility to comply with third party license terms applicable
- * to your use of third party software (including open source software) that
- * may accompany Microchip software.
- *
- * THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES,
- * WHETHER EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE,
- * INCLUDING ANY IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY,
- * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL MICROCHIP BE
- * LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE, INCIDENTAL OR CONSEQUENTIAL
- * LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND WHATSOEVER RELATED TO THE
- * SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS BEEN ADVISED OF THE
- * POSSIBILITY OR THE DAMAGES ARE FORESEEABLE.  TO THE FULLEST EXTENT
- * ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY
- * RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
- * THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.
- *
- * \asf_license_stop
- *
- */
-
-#include "hal_calendar.h"
-#include <utils.h>
-#include <utils_assert.h>
-#include <hal_atomic.h>
-
-#define CALENDAR_VERSION 0x00000001u
-#define SECS_IN_LEAP_YEAR 31622400
-#define SECS_IN_NON_LEAP_YEAR 31536000
-#define SECS_IN_31DAYS 2678400
-#define SECS_IN_30DAYS 2592000
-#define SECS_IN_29DAYS 2505600
-#define SECS_IN_28DAYS 2419200
-#define SECS_IN_DAY 86400
-#define SECS_IN_HOUR 3600
-#define SECS_IN_MINUTE 60
-#define DEFAULT_BASE_YEAR 1970
-
-#define SET_ALARM_BUSY 1
-#define PROCESS_ALARM_BUSY 2
-
-/** \brief leap year check
- *  \retval false  not leap year.
- *  \retval true  leap year.
- */
-static bool leap_year(uint16_t year)
-{
-	if (year & 3) {
-		return false;
-	} else {
-		return true;
-	}
-}
-
-/** \brief calculate the seconds in specified year/month
- *  \retval 0  month error.
- */
-static uint32_t get_secs_in_month(uint32_t year, uint8_t month)
-{
-	uint32_t sec_in_month = 0;
-
-	if (leap_year(year)) {
-		switch (month) {
-		case 1:
-		case 3:
-		case 5:
-		case 7:
-		case 8:
-		case 10:
-		case 12:
-			sec_in_month = SECS_IN_31DAYS;
-			break;
-		case 2:
-			sec_in_month = SECS_IN_29DAYS;
-			break;
-		case 4:
-		case 6:
-		case 9:
-		case 11:
-			sec_in_month = SECS_IN_30DAYS;
-			break;
-		default:
-			break;
-		}
-	} else {
-		switch (month) {
-		case 1:
-		case 3:
-		case 5:
-		case 7:
-		case 8:
-		case 10:
-		case 12:
-			sec_in_month = SECS_IN_31DAYS;
-			break;
-		case 2:
-			sec_in_month = SECS_IN_28DAYS;
-			break;
-		case 4:
-		case 6:
-		case 9:
-		case 11:
-			sec_in_month = SECS_IN_30DAYS;
-			break;
-		default:
-			break;
-		}
-	}
-
-	return sec_in_month;
-}
-
-/** \brief convert timestamp to date/time
- */
-static int32_t convert_timestamp_to_datetime(struct calendar_descriptor *const calendar, uint32_t ts,
-                                             struct calendar_date_time *dt)
-{
-	uint32_t tmp, sec_in_year, sec_in_month;
-	uint32_t tmp_year    = calendar->base_year;
-	uint8_t  tmp_month   = 1;
-	uint8_t  tmp_day     = 1;
-	uint8_t  tmp_hour    = 0;
-	uint8_t  tmp_minutes = 0;
-
-	tmp = ts;
-
-	/* Find year */
-	while (true) {
-		sec_in_year = leap_year(tmp_year) ? SECS_IN_LEAP_YEAR : SECS_IN_NON_LEAP_YEAR;
-
-		if (tmp >= sec_in_year) {
-			tmp -= sec_in_year;
-			tmp_year++;
-		} else {
-			break;
-		}
-	}
-	/* Find month of year */
-	while (true) {
-		sec_in_month = get_secs_in_month(tmp_year, tmp_month);
-
-		if (tmp >= sec_in_month) {
-			tmp -= sec_in_month;
-			tmp_month++;
-		} else {
-			break;
-		}
-	}
-	/* Find day of month */
-	while (true) {
-		if (tmp >= SECS_IN_DAY) {
-			tmp -= SECS_IN_DAY;
-			tmp_day++;
-		} else {
-			break;
-		}
-	}
-	/* Find hour of day */
-	while (true) {
-		if (tmp >= SECS_IN_HOUR) {
-			tmp -= SECS_IN_HOUR;
-			tmp_hour++;
-		} else {
-			break;
-		}
-	}
-	/* Find minute in hour */
-	while (true) {
-		if (tmp >= SECS_IN_MINUTE) {
-			tmp -= SECS_IN_MINUTE;
-			tmp_minutes++;
-		} else {
-			break;
-		}
-	}
-
-	dt->date.year  = tmp_year;
-	dt->date.month = tmp_month;
-	dt->date.day   = tmp_day;
-	dt->time.hour  = tmp_hour;
-	dt->time.min   = tmp_minutes;
-	dt->time.sec   = tmp;
-
-	return ERR_NONE;
-}
-
-/** \brief convert date/time to timestamp
- *  \return timestamp
- */
-static uint32_t convert_datetime_to_timestamp(struct calendar_descriptor *const calendar, struct calendar_date_time *dt)
-{
-	uint32_t tmp = 0;
-	uint32_t i   = 0;
-	uint8_t  year, month, day, hour, minutes, seconds;
-
-	year    = dt->date.year - calendar->base_year;
-	month   = dt->date.month;
-	day     = dt->date.day;
-	hour    = dt->time.hour;
-	minutes = dt->time.min;
-	seconds = dt->time.sec;
-
-	/* tot up year field */
-	for (i = 0; i < year; ++i) {
-		if (leap_year(calendar->base_year + i)) {
-			tmp += SECS_IN_LEAP_YEAR;
-		} else {
-			tmp += SECS_IN_NON_LEAP_YEAR;
-		}
-	}
-
-	/* tot up month field */
-	for (i = 1; i < month; ++i) {
-		tmp += get_secs_in_month(dt->date.year, i);
-	}
-
-	/* tot up day/hour/minute/second fields */
-	tmp += (day - 1) * SECS_IN_DAY;
-	tmp += hour * SECS_IN_HOUR;
-	tmp += minutes * SECS_IN_MINUTE;
-	tmp += seconds;
-
-	return tmp;
-}
-
-/** \brief calibrate timestamp to make desired timestamp ahead of current timestamp
- */
-static void calibrate_timestamp(struct calendar_descriptor *const calendar, struct calendar_alarm *alarm,
-                                struct calendar_alarm *current_dt)
-{
-	uint32_t alarm_ts;
-	uint32_t current_ts = current_dt->cal_alarm.timestamp;
-
-	(void)calendar;
-
-	alarm_ts = alarm->cal_alarm.timestamp;
-
-	/* calibrate timestamp */
-	switch (alarm->cal_alarm.option) {
-	case CALENDAR_ALARM_MATCH_SEC:
-
-		if (alarm_ts <= current_ts) {
-			alarm_ts += SECS_IN_MINUTE;
-		}
-
-		break;
-	case CALENDAR_ALARM_MATCH_MIN:
-
-		if (alarm_ts <= current_ts) {
-			alarm_ts += SECS_IN_HOUR;
-		}
-
-		break;
-	case CALENDAR_ALARM_MATCH_HOUR:
-
-		if (alarm_ts <= current_ts) {
-			alarm_ts += SECS_IN_DAY;
-		}
-
-		break;
-	case CALENDAR_ALARM_MATCH_DAY:
-
-		if (alarm_ts <= current_ts) {
-			alarm_ts += get_secs_in_month(current_dt->cal_alarm.datetime.date.year,
-			                              current_dt->cal_alarm.datetime.date.month);
-		}
-
-		break;
-	case CALENDAR_ALARM_MATCH_MONTH:
-
-		if (alarm_ts <= current_ts) {
-			if (leap_year(current_dt->cal_alarm.datetime.date.year)) {
-				alarm_ts += SECS_IN_LEAP_YEAR;
-			} else {
-				alarm_ts += SECS_IN_NON_LEAP_YEAR;
-			}
-		}
-
-		break;
-	/* do nothing for year match */
-	case CALENDAR_ALARM_MATCH_YEAR:
-	default:
-		break;
-	}
-
-	/* desired timestamp after calibration */
-	alarm->cal_alarm.timestamp = alarm_ts;
-}
-
-/** \brief complete alarm to absolute date/time, then fill up the timestamp
- */
-static void fill_alarm(struct calendar_descriptor *const calendar, struct calendar_alarm *alarm)
-{
-	struct calendar_alarm current_dt;
-	uint32_t              tmp, current_ts;
-
-	/* get current date/time */
-	current_ts = _calendar_get_counter(&calendar->device);
-	convert_timestamp_to_datetime(calendar, current_ts, &current_dt.cal_alarm.datetime);
-
-	current_dt.cal_alarm.timestamp = current_ts;
-
-	/* complete alarm */
-	switch (alarm->cal_alarm.option) {
-	case CALENDAR_ALARM_MATCH_SEC:
-		alarm->cal_alarm.datetime.date.year  = current_dt.cal_alarm.datetime.date.year;
-		alarm->cal_alarm.datetime.date.month = current_dt.cal_alarm.datetime.date.month;
-		alarm->cal_alarm.datetime.date.day   = current_dt.cal_alarm.datetime.date.day;
-		alarm->cal_alarm.datetime.time.hour  = current_dt.cal_alarm.datetime.time.hour;
-		alarm->cal_alarm.datetime.time.min   = current_dt.cal_alarm.datetime.time.min;
-		break;
-	case CALENDAR_ALARM_MATCH_MIN:
-		alarm->cal_alarm.datetime.date.year  = current_dt.cal_alarm.datetime.date.year;
-		alarm->cal_alarm.datetime.date.month = current_dt.cal_alarm.datetime.date.month;
-		alarm->cal_alarm.datetime.date.day   = current_dt.cal_alarm.datetime.date.day;
-		alarm->cal_alarm.datetime.time.hour  = current_dt.cal_alarm.datetime.time.hour;
-		break;
-	case CALENDAR_ALARM_MATCH_HOUR:
-		alarm->cal_alarm.datetime.date.year  = current_dt.cal_alarm.datetime.date.year;
-		alarm->cal_alarm.datetime.date.month = current_dt.cal_alarm.datetime.date.month;
-		alarm->cal_alarm.datetime.date.day   = current_dt.cal_alarm.datetime.date.day;
-		break;
-	case CALENDAR_ALARM_MATCH_DAY:
-		alarm->cal_alarm.datetime.date.year  = current_dt.cal_alarm.datetime.date.year;
-		alarm->cal_alarm.datetime.date.month = current_dt.cal_alarm.datetime.date.month;
-		break;
-	case CALENDAR_ALARM_MATCH_MONTH:
-		alarm->cal_alarm.datetime.date.year = current_dt.cal_alarm.datetime.date.year;
-		break;
-	case CALENDAR_ALARM_MATCH_YEAR:
-		break;
-	default:
-		break;
-	}
-
-	/* fill up the timestamp */
-	tmp                        = convert_datetime_to_timestamp(calendar, &alarm->cal_alarm.datetime);
-	alarm->cal_alarm.timestamp = tmp;
-
-	/* calibrate the timestamp */
-	calibrate_timestamp(calendar, alarm, &current_dt);
-	convert_timestamp_to_datetime(calendar, alarm->cal_alarm.timestamp, &alarm->cal_alarm.datetime);
-}
-
-/** \brief add new alarm into the list in ascending order
- */
-static int32_t calendar_add_new_alarm(struct list_descriptor *list, struct calendar_alarm *alarm)
-{
-	struct calendar_descriptor *calendar = CONTAINER_OF(list, struct calendar_descriptor, alarms);
-	struct calendar_alarm *     head, *it, *prev = NULL;
-
-	/*get the head of alarms list*/
-	head = (struct calendar_alarm *)list_get_head(list);
-
-	/*if head is null, insert new alarm as head*/
-	if (!head) {
-		list_insert_as_head(list, alarm);
-		_calendar_set_comp(&calendar->device, alarm->cal_alarm.timestamp);
-		return ERR_NONE;
-	}
-
-	/*insert the new alarm in accending order, the head will be invoked firstly */
-	for (it = head; it; it = (struct calendar_alarm *)list_get_next_element(it)) {
-		if (alarm->cal_alarm.timestamp <= it->cal_alarm.timestamp) {
-			break;
-		}
-
-		prev = it;
-	}
-
-	/*insert new alarm into the list */
-	if (it == head) {
-		list_insert_as_head(list, alarm);
-		/*get the head and set it into register*/
-		_calendar_set_comp(&calendar->device, alarm->cal_alarm.timestamp);
-
-	} else {
-		list_insert_after(prev, alarm);
-	}
-
-	return ERR_NONE;
-}
-
-/** \brief callback for alarm
- */
-static void calendar_alarm(struct calendar_dev *const dev)
-{
-	struct calendar_descriptor *calendar = CONTAINER_OF(dev, struct calendar_descriptor, device);
-
-	struct calendar_alarm *head, *it, current_dt;
-
-	if ((calendar->flags & SET_ALARM_BUSY) || (calendar->flags & PROCESS_ALARM_BUSY)) {
-		calendar->flags |= PROCESS_ALARM_BUSY;
-		return;
-	}
-
-	/* get current timestamp */
-	current_dt.cal_alarm.timestamp = _calendar_get_counter(dev);
-
-	/* get the head */
-	head = (struct calendar_alarm *)list_get_head(&calendar->alarms);
-	ASSERT(head);
-
-	/* remove all alarms and invoke them*/
-	for (it = head; it; it = (struct calendar_alarm *)list_get_head(&calendar->alarms)) {
-		/* check the timestamp with current timestamp*/
-		if (it->cal_alarm.timestamp <= current_dt.cal_alarm.timestamp) {
-			list_remove_head(&calendar->alarms);
-			it->callback(calendar);
-
-			if (it->cal_alarm.mode == REPEAT) {
-				calibrate_timestamp(calendar, it, &current_dt);
-				convert_timestamp_to_datetime(calendar, it->cal_alarm.timestamp, &it->cal_alarm.datetime);
-				calendar_add_new_alarm(&calendar->alarms, it);
-			}
-		} else {
-			break;
-		}
-	}
-
-	/*if no alarm in the list, register null */
-	if (!it) {
-		_calendar_register_callback(&calendar->device, NULL);
-		return;
-	}
-
-	/*put the new head into register */
-	_calendar_set_comp(&calendar->device, it->cal_alarm.timestamp);
-}
-
-/** \brief Initialize Calendar
- */
-int32_t calendar_init(struct calendar_descriptor *const calendar, const void *hw)
-{
-	int32_t ret = 0;
-
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	if (calendar->device.hw == hw) {
-		/* Already initialized with current configuration */
-		return ERR_NONE;
-	} else if (calendar->device.hw != NULL) {
-		/* Initialized with another configuration */
-		return ERR_ALREADY_INITIALIZED;
-	}
-	calendar->device.hw = (void *)hw;
-	ret                 = _calendar_init(&calendar->device);
-	calendar->base_year = DEFAULT_BASE_YEAR;
-
-	return ret;
-}
-
-/** \brief Reset the Calendar
- */
-int32_t calendar_deinit(struct calendar_descriptor *const calendar)
-{
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	if (calendar->device.hw == NULL) {
-		return ERR_NOT_INITIALIZED;
-	}
-	_calendar_deinit(&calendar->device);
-	calendar->device.hw = NULL;
-
-	return ERR_NONE;
-}
-
-/** \brief Enable the Calendar
- */
-int32_t calendar_enable(struct calendar_descriptor *const calendar)
-{
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	_calendar_enable(&calendar->device);
-
-	return ERR_NONE;
-}
-
-/** \brief Disable the Calendar
- */
-int32_t calendar_disable(struct calendar_descriptor *const calendar)
-{
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	_calendar_disable(&calendar->device);
-
-	return ERR_NONE;
-}
-
-/** \brief Set base year for calendar
- */
-int32_t calendar_set_baseyear(struct calendar_descriptor *const calendar, const uint32_t p_base_year)
-{
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	calendar->base_year = p_base_year;
-
-	return ERR_NONE;
-}
-
-/** \brief Set time for calendar
- */
-int32_t calendar_set_time(struct calendar_descriptor *const calendar, struct calendar_time *const p_calendar_time)
-{
-	struct calendar_date_time dt;
-	uint32_t                  current_ts, new_ts;
-
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	/* convert time to timestamp */
-	current_ts = _calendar_get_counter(&calendar->device);
-	convert_timestamp_to_datetime(calendar, current_ts, &dt);
-	dt.time.sec  = p_calendar_time->sec;
-	dt.time.min  = p_calendar_time->min;
-	dt.time.hour = p_calendar_time->hour;
-
-	new_ts = convert_datetime_to_timestamp(calendar, &dt);
-
-	_calendar_set_counter(&calendar->device, new_ts);
-
-	return ERR_NONE;
-}
-
-/** \brief Set date for calendar
- */
-int32_t calendar_set_date(struct calendar_descriptor *const calendar, struct calendar_date *const p_calendar_date)
-{
-	struct calendar_date_time dt;
-	uint32_t                  current_ts, new_ts;
-
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	/* convert date to timestamp */
-	current_ts = _calendar_get_counter(&calendar->device);
-	convert_timestamp_to_datetime(calendar, current_ts, &dt);
-	dt.date.day   = p_calendar_date->day;
-	dt.date.month = p_calendar_date->month;
-	dt.date.year  = p_calendar_date->year;
-
-	new_ts = convert_datetime_to_timestamp(calendar, &dt);
-
-	_calendar_set_counter(&calendar->device, new_ts);
-
-	return ERR_NONE;
-}
-
-/** \brief Get date/time for calendar
- */
-int32_t calendar_get_date_time(struct calendar_descriptor *const calendar, struct calendar_date_time *const date_time)
-{
-	uint32_t current_ts;
-
-	/* Sanity check arguments */
-	ASSERT(calendar);
-
-	/* convert current timestamp to date/time */
-	current_ts = _calendar_get_counter(&calendar->device);
-	convert_timestamp_to_datetime(calendar, current_ts, date_time);
-
-	return ERR_NONE;
-}
-
-/** \brief Set alarm for calendar
- */
-int32_t calendar_set_alarm(struct calendar_descriptor *const calendar, struct calendar_alarm *const alarm,
-                           calendar_cb_alarm_t callback)
-{
-	struct calendar_alarm *head;
-
-	/* Sanity check arguments */
-	ASSERT(calendar);
-	ASSERT(alarm);
-
-	alarm->callback = callback;
-
-	fill_alarm(calendar, alarm);
-
-	calendar->flags |= SET_ALARM_BUSY;
-
-	head = (struct calendar_alarm *)list_get_head(&calendar->alarms);
-
-	if (head != NULL) {
-		/* already added */
-		if (is_list_element(&calendar->alarms, alarm)) {
-			if (callback == NULL) {
-				/* remove alarm */
-				list_delete_element(&calendar->alarms, alarm);
-
-				if (!list_get_head(&calendar->alarms)) {
-					_calendar_register_callback(&calendar->device, NULL);
-				}
-			} else {
-				/* re-add */
-				list_delete_element(&calendar->alarms, alarm);
-				calendar_add_new_alarm(&calendar->alarms, alarm);
-			}
-		} else if (callback != NULL) {
-			calendar_add_new_alarm(&calendar->alarms, alarm);
-		}
-
-		calendar->flags &= ~SET_ALARM_BUSY;
-
-		if (calendar->flags & PROCESS_ALARM_BUSY) {
-			CRITICAL_SECTION_ENTER()
-			calendar->flags &= ~PROCESS_ALARM_BUSY;
-			_calendar_set_irq(&calendar->device);
-			CRITICAL_SECTION_LEAVE()
-		}
-	} else if (callback != NULL) {
-		/* if head is NULL, Register callback*/
-		_calendar_register_callback(&calendar->device, calendar_alarm);
-		calendar_add_new_alarm(&calendar->alarms, alarm);
-	}
-
-	calendar->flags &= ~SET_ALARM_BUSY;
-
-	return ERR_NONE;
-}
-
-/** \brief Retrieve driver version
- *  \return Current driver version
- */
-uint32_t calendar_get_version(void)
-{
-	return CALENDAR_VERSION;
-}
diff --git a/watch-library/hpl/rtc/hpl_rtc.c b/watch-library/hpl/rtc/hpl_rtc.c
deleted file mode 100644
index e580fa78..00000000
--- a/watch-library/hpl/rtc/hpl_rtc.c
+++ /dev/null
@@ -1,430 +0,0 @@
-
-/**
- * \file
- *
- * \brief RTC Driver
- *
- * Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.
- *
- * \asf_license_start
- *
- * \page License
- *
- * Subject to your compliance with these terms, you may use Microchip
- * software and any derivatives exclusively with Microchip products.
- * It is your responsibility to comply with third party license terms applicable
- * to your use of third party software (including open source software) that
- * may accompany Microchip software.
- *
- * THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES,
- * WHETHER EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE,
- * INCLUDING ANY IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY,
- * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL MICROCHIP BE
- * LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE, INCIDENTAL OR CONSEQUENTIAL
- * LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND WHATSOEVER RELATED TO THE
- * SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS BEEN ADVISED OF THE
- * POSSIBILITY OR THE DAMAGES ARE FORESEEABLE.  TO THE FULLEST EXTENT
- * ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY
- * RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
- * THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.
- *
- * \asf_license_stop
- *
- */
-
-#include <hpl_calendar.h>
-#include <utils_assert.h>
-#include <hpl_rtc_config.h>
-
-/*!< Pointer to hpl device */
-static struct calendar_dev *_rtc_dev = NULL;
-
-/**
- * \brief Initializes the RTC module with given configurations.
- */
-int32_t _calendar_init(struct calendar_dev *const dev)
-{
-	ASSERT(dev && dev->hw);
-
-	_rtc_dev = dev;
-
-	if (hri_rtcmode0_get_CTRLA_ENABLE_bit(dev->hw)) {
-#if !CONF_RTC_INIT_RESET
-		return ERR_DENIED;
-#else
-		hri_rtcmode0_clear_CTRLA_ENABLE_bit(dev->hw);
-		hri_rtcmode0_wait_for_sync(dev->hw, RTC_MODE0_SYNCBUSY_ENABLE);
-#endif
-	}
-	hri_rtcmode0_set_CTRLA_SWRST_bit(dev->hw);
-	hri_rtcmode0_wait_for_sync(dev->hw, RTC_MODE0_SYNCBUSY_SWRST);
-
-#if CONF_RTC_EVENT_CONTROL_ENABLE == 1
-	hri_rtcmode0_write_EVCTRL_reg(
-	    dev->hw,
-	    (CONF_RTC_PEREO0 << RTC_MODE0_EVCTRL_PEREO0_Pos) | (CONF_RTC_PEREO1 << RTC_MODE0_EVCTRL_PEREO1_Pos)
-	        | (CONF_RTC_PEREO2 << RTC_MODE0_EVCTRL_PEREO2_Pos) | (CONF_RTC_PEREO3 << RTC_MODE0_EVCTRL_PEREO3_Pos)
-	        | (CONF_RTC_PEREO4 << RTC_MODE0_EVCTRL_PEREO4_Pos) | (CONF_RTC_PEREO5 << RTC_MODE0_EVCTRL_PEREO5_Pos)
-	        | (CONF_RTC_PEREO6 << RTC_MODE0_EVCTRL_PEREO6_Pos) | (CONF_RTC_PEREO7 << RTC_MODE0_EVCTRL_PEREO7_Pos)
-	        | (CONF_RTC_COMPE0 << RTC_MODE0_EVCTRL_CMPEO_Pos) | (CONF_RTC_OVFEO << RTC_MODE0_EVCTRL_OVFEO_Pos));
-#endif
-
-	hri_rtcmode0_write_CTRLA_reg(dev->hw, RTC_MODE0_CTRLA_PRESCALER(CONF_RTC_PRESCALER) | RTC_MODE0_CTRLA_COUNTSYNC);
-
-	hri_rtc_write_TAMPCTRL_reg(
-	    dev->hw,
-	    (CONF_RTC_TAMPER_INACT_0 << RTC_TAMPCTRL_IN0ACT_Pos) | (CONF_RTC_TAMPER_INACT_1 << RTC_TAMPCTRL_IN1ACT_Pos)
-	        | (CONF_RTC_TAMPER_INACT_2 << RTC_TAMPCTRL_IN2ACT_Pos)
-	        | (CONF_RTC_TAMPER_INACT_3 << RTC_TAMPCTRL_IN3ACT_Pos)
-	        | (CONF_RTC_TAMPER_INACT_4 << RTC_TAMPCTRL_IN4ACT_Pos) | (CONF_RTC_TAMP_LVL_0 << RTC_TAMPCTRL_TAMLVL0_Pos)
-	        | (CONF_RTC_TAMP_LVL_1 << RTC_TAMPCTRL_TAMLVL1_Pos) | (CONF_RTC_TAMP_LVL_2 << RTC_TAMPCTRL_TAMLVL2_Pos)
-	        | (CONF_RTC_TAMP_LVL_3 << RTC_TAMPCTRL_TAMLVL3_Pos) | (CONF_RTC_TAMP_LVL_4 << RTC_TAMPCTRL_TAMLVL4_Pos)
-	        | (CONF_RTC_TAMP_DEBNC_0 << RTC_TAMPCTRL_DEBNC0_Pos) | (CONF_RTC_TAMP_DEBNC_1 << RTC_TAMPCTRL_DEBNC1_Pos)
-	        | (CONF_RTC_TAMP_DEBNC_2 << RTC_TAMPCTRL_DEBNC2_Pos) | (CONF_RTC_TAMP_DEBNC_3 << RTC_TAMPCTRL_DEBNC3_Pos)
-	        | (CONF_RTC_TAMP_DEBNC_4 << RTC_TAMPCTRL_DEBNC4_Pos));
-
-	if ((CONF_RTC_TAMPER_INACT_0 == TAMPER_MODE_ACTL) | (CONF_RTC_TAMPER_INACT_1 == TAMPER_MODE_ACTL)
-	    | (CONF_RTC_TAMPER_INACT_2 == TAMPER_MODE_ACTL) | (CONF_RTC_TAMPER_INACT_3 == TAMPER_MODE_ACTL)
-	    | (CONF_RTC_TAMPER_INACT_4 == TAMPER_MODE_ACTL)) {
-		hri_rtcmode0_set_CTRLB_RTCOUT_bit(dev->hw);
-	}
-	return ERR_NONE;
-}
-
-/**
- * \brief Deinit the RTC module
- */
-int32_t _calendar_deinit(struct calendar_dev *const dev)
-{
-	ASSERT(dev && dev->hw);
-
-	NVIC_DisableIRQ(RTC_IRQn);
-	dev->callback_alarm = NULL;
-	dev->callback_tick = NULL;
-	dev->callback_tamper = NULL;
-
-	hri_rtcmode0_clear_CTRLA_ENABLE_bit(dev->hw);
-	hri_rtcmode0_set_CTRLA_SWRST_bit(dev->hw);
-
-	return ERR_NONE;
-}
-
-/**
- * \brief Enable the RTC module
- */
-int32_t _calendar_enable(struct calendar_dev *const dev)
-{
-	ASSERT(dev && dev->hw);
-
-	hri_rtcmode0_set_CTRLA_ENABLE_bit(dev->hw);
-
-	return ERR_NONE;
-}
-
-/**
- * \brief Disable the RTC module
- */
-int32_t _calendar_disable(struct calendar_dev *const dev)
-{
-	ASSERT(dev && dev->hw);
-
-	hri_rtcmode0_clear_CTRLA_ENABLE_bit(dev->hw);
-
-	return ERR_NONE;
-}
-
-/**
- * \brief Set the current calendar time to desired time.
- */
-int32_t _calendar_set_counter(struct calendar_dev *const dev, const uint32_t counter)
-{
-	ASSERT(dev && dev->hw);
-
-	hri_rtcmode0_write_COUNT_reg(dev->hw, counter);
-
-	return ERR_NONE;
-}
-
-/**
- * \brief Get current counter
- */
-uint32_t _calendar_get_counter(struct calendar_dev *const dev)
-{
-	ASSERT(dev && dev->hw);
-
-	return hri_rtcmode0_read_COUNT_reg(dev->hw);
-}
-
-/**
- * \brief Set the compare for the specified value.
- */
-int32_t _calendar_set_comp(struct calendar_dev *const dev, const uint32_t comp)
-{
-	ASSERT(dev && dev->hw);
-
-	hri_rtcmode0_write_COMP_reg(dev->hw, 0, comp);
-
-	return ERR_NONE;
-}
-
-/**
- * \brief Get the compare value
- */
-uint32_t _calendar_get_comp(struct calendar_dev *const dev)
-{
-	ASSERT(dev && dev->hw);
-
-	return hri_rtcmode0_read_COMP_reg(dev->hw, 0);
-}
-
-/**
- * \brief Find tamper is detected on specified pin
- */
-bool _is_tamper_detected(struct calendar_dev *const dev, enum tamper_id tamper_id_pin)
-{
-	bool value;
-
-	ASSERT(dev && dev->hw);
-
-	value = ((hri_rtc_read_TAMPID_reg(dev->hw) >> tamper_id_pin) & 0x01);
-	return value;
-}
-
-/**
- * \brief Clear the Tamper ID flag
- */
-int32_t _tamper_clear_tampid_flag(struct calendar_dev *const dev, enum tamper_id tamper_id_pin)
-{
-	ASSERT(dev && dev->hw);
-
-	hri_rtc_write_TAMPID_reg(dev->hw, (true << tamper_id_pin));
-
-	return ERR_NONE;
-}
-
-/**
- * \brief Enable Tamper Debounce Asynchronous Feature
- */
-int32_t _tamper_enable_debounce_asynchronous(struct calendar_dev *const dev)
-{
-	int32_t return_value;
-
-	hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, false);
-
-	while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-	}
-
-	if (hri_rtcmode0_read_CTRLA_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		return_value = ERR_FAILURE;
-	} else {
-		hri_rtcmode0_write_CTRLB_DEBASYNC_bit(dev->hw, true);
-		return_value = ERR_NONE;
-		while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		}
-		hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, true);
-	}
-
-	return return_value;
-}
-
-/**
- * \brief Disable Tamper Debounce Asynchronous Feature
- */
-int32_t _tamper_disable_debounce_asynchronous(struct calendar_dev *const dev)
-{
-	int32_t return_value;
-
-	hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, false);
-
-	while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-	}
-
-	if (hri_rtcmode0_read_CTRLA_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		return_value = ERR_FAILURE;
-	} else {
-		hri_rtcmode0_write_CTRLB_DEBASYNC_bit(dev->hw, false);
-		return_value = ERR_NONE;
-		while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		}
-		hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, true);
-	}
-
-	return return_value;
-}
-
-/**
- * \brief Enable Tamper Debounce Majority Feature
- */
-int32_t _tamper_enable_debounce_majority(struct calendar_dev *const dev)
-{
-	int32_t return_value;
-
-	hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, false);
-
-	while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-	}
-
-	if (hri_rtcmode0_read_CTRLA_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		return_value = ERR_FAILURE;
-	} else {
-		hri_rtcmode0_write_CTRLB_DEBMAJ_bit(dev->hw, true);
-		return_value = ERR_NONE;
-
-		while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		}
-		hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, true);
-	}
-
-	return return_value;
-}
-
-/**
- * \brief Disable Tamper Debounce Majority Feature
- */
-int32_t _tamper_disable_debounce_majority(struct calendar_dev *const dev)
-{
-	int32_t return_value;
-
-	hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, false);
-
-	while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-	}
-
-	if (hri_rtcmode0_read_CTRLA_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		return_value = ERR_FAILURE;
-	} else {
-		hri_rtcmode0_write_CTRLB_DEBMAJ_bit(dev->hw, false);
-		return_value = ERR_NONE;
-
-		while (hri_rtcmode0_read_SYNCBUSY_reg(dev->hw) & RTC_MODE2_CTRLA_ENABLE) {
-		}
-		hri_rtcmode0_write_CTRLA_ENABLE_bit(dev->hw, true);
-	}
-
-	return return_value;
-}
-
-int32_t _prescaler_register_callback(struct calendar_dev *const dev, calendar_drv_cb_t callback)
-{
-	ASSERT(dev && dev->hw);
-
-	/* Check callback */
-	if (callback != NULL) {
-		/* register the callback */
-		dev->callback_tick = callback;
-
-		/* enable RTC_IRQn */
-		NVIC_ClearPendingIRQ(RTC_IRQn);
-		NVIC_EnableIRQ(RTC_IRQn);
-
-		/* enable periodic interrupt */
-		hri_rtcmode0_set_INTEN_PER7_bit(dev->hw);
-	} else {
-		/* disable periodic interrupt */
-		hri_rtcmode0_clear_INTEN_PER7_bit(dev->hw);
-	}
-
-	return ERR_NONE;
-}
-
-int32_t _extwake_register_callback(struct calendar_dev *const dev, calendar_drv_extwake_cb_t callback)
-{
-	ASSERT(dev && dev->hw);
-
-	/* Check callback */
-	if (callback != NULL) {
-		/* register the callback */
-		dev->callback_tamper = callback;
-
-		/* enable RTC_IRQn */
-		NVIC_ClearPendingIRQ(RTC_IRQn);
-		NVIC_EnableIRQ(RTC_IRQn);
-
-		hri_rtcmode0_clear_interrupt_TAMPER_bit(dev->hw);
-		/* enable tamper interrupt */
-		hri_rtcmode0_set_INTEN_TAMPER_bit(dev->hw);
-	} else {
-		/* disable tamper interrupt */
-		hri_rtcmode0_clear_INTEN_TAMPER_bit(dev->hw);
-	}
-
-	return ERR_NONE;
-}
-/**
- * \brief Registers callback for the specified callback type
- */
-int32_t _calendar_register_callback(struct calendar_dev *const dev, calendar_drv_cb_t callback)
-{
-	ASSERT(dev && dev->hw);
-
-	/* Check callback */
-	if (callback != NULL) {
-		/* register the callback */
-		dev->callback_alarm = callback;
-
-		/* enable RTC_IRQn */
-		NVIC_ClearPendingIRQ(RTC_IRQn);
-		NVIC_EnableIRQ(RTC_IRQn);
-
-		/* enable cmp */
-		hri_rtcmode0_set_INTEN_CMP0_bit(dev->hw);
-	} else {
-		/* disable cmp */
-		hri_rtcmode0_clear_INTEN_CMP0_bit(dev->hw);
-	}
-
-	return ERR_NONE;
-}
-
-/**
- * \brief RTC interrupt handler
- *
- * \param[in] dev The pointer to calendar device struct
- */
-static void _rtc_interrupt_handler(struct calendar_dev *dev)
-{
-	/* Read and mask interrupt flag register */
-	uint16_t interrupt_status  = hri_rtcmode0_read_INTFLAG_reg(dev->hw);
-	uint16_t interrupt_enabled = hri_rtcmode0_read_INTEN_reg(dev->hw);
-
-	if ((interrupt_status & interrupt_enabled) & RTC_MODE2_INTFLAG_ALARM0) {
-		if (dev->callback_alarm != NULL) {
-			dev->callback_alarm();
-		}
-
-		/* Clear interrupt flag */
-		hri_rtcmode0_clear_interrupt_CMP0_bit(dev->hw);
-	} else if ((interrupt_status & interrupt_enabled) & RTC_MODE2_INTFLAG_PER7) {
-		if (dev->callback_tick != NULL) {
-			dev->callback_tick();
-		}
-
-		/* Clear interrupt flag */
-		hri_rtcmode0_clear_interrupt_PER7_bit(dev->hw);
-	} else if ((interrupt_status & interrupt_enabled) & RTC_MODE2_INTFLAG_TAMPER) {
-		uint8_t reason = hri_rtc_get_TAMPID_reg(dev->hw, 0x1F);
-		if (dev->callback_tamper != NULL) {
-			dev->callback_tamper(reason);
-		}
-		hri_rtc_write_TAMPID_reg(dev->hw, reason);
-
-		/* Clear interrupt flag */
-		hri_rtcmode0_clear_interrupt_TAMPER_bit(dev->hw);
-	}
-}
-/**
- * \brief Set calendar IRQ
- */
-void _calendar_set_irq(struct calendar_dev *const dev)
-{
-	(void)dev;
-	NVIC_SetPendingIRQ(RTC_IRQn);
-}
-
-/**
- * \brief Rtc interrupt handler
- */
-void RTC_Handler(void)
-{
-	_rtc_interrupt_handler(_rtc_dev);
-}
diff --git a/watch-library/hpl/rtc/hpl_rtc_base.h b/watch-library/hpl/rtc/hpl_rtc_base.h
deleted file mode 100644
index 06e3bd79..00000000
--- a/watch-library/hpl/rtc/hpl_rtc_base.h
+++ /dev/null
@@ -1,52 +0,0 @@
-/**
- * \file
- *
- * \brief RTC
- *
- * Copyright (c) 2016-2018 Microchip Technology Inc. and its subsidiaries.
- *
- * \asf_license_start
- *
- * \page License
- *
- * Subject to your compliance with these terms, you may use Microchip
- * software and any derivatives exclusively with Microchip products.
- * It is your responsibility to comply with third party license terms applicable
- * to your use of third party software (including open source software) that
- * may accompany Microchip software.
- *
- * THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES,
- * WHETHER EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE,
- * INCLUDING ANY IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY,
- * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL MICROCHIP BE
- * LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE, INCIDENTAL OR CONSEQUENTIAL
- * LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND WHATSOEVER RELATED TO THE
- * SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS BEEN ADVISED OF THE
- * POSSIBILITY OR THE DAMAGES ARE FORESEEABLE.  TO THE FULLEST EXTENT
- * ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY
- * RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
- * THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.
- *
- * \asf_license_stop
- */
-
-#ifndef _HPL_RTC2_V200_H_INCLUDED
-#define _HPL_RTC2_V200_H_INCLUDED
-
-#include <hpl_timer.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
- * \brief Retrieve timer helper functions
- *
- * \return A pointer to set of timer helper functions
- */
-struct _timer_hpl_interface *_rtc_get_timer(void);
-
-#ifdef __cplusplus
-}
-#endif
-#endif /* _HPL_RTC2_V200_H_INCLUDED */
diff --git a/watch-library/hw/driver_init.c b/watch-library/hw/driver_init.c
index 2cfdced7..09723bec 100644
--- a/watch-library/hw/driver_init.c
+++ b/watch-library/hw/driver_init.c
@@ -13,19 +13,8 @@
 
 struct slcd_sync_descriptor SEGMENT_LCD_0;
 
-struct calendar_descriptor CALENDAR_0;
-
 struct i2c_m_sync_desc I2C_0;
 
-void CALENDAR_0_CLOCK_init(void) {
-	hri_mclk_set_APBAMASK_RTC_bit(MCLK);
-}
-
-void CALENDAR_0_init(void) {
-	CALENDAR_0_CLOCK_init();
-	calendar_init(&CALENDAR_0, RTC);
-}
-
 void I2C_0_PORT_init(void) {
 
 	gpio_set_pin_pull_mode(SDA,
diff --git a/watch-library/hw/driver_init.h b/watch-library/hw/driver_init.h
index 019a0b56..002f07aa 100644
--- a/watch-library/hw/driver_init.h
+++ b/watch-library/hw/driver_init.h
@@ -31,43 +31,22 @@ extern "C" {
 #include <hal_io.h>
 #include <hal_sleep.h>
 #include <hal_ext_irq.h>
-#include <hal_calendar.h>
 #include <hal_i2c_m_sync.h>
 #include <hal_delay.h>
 #include <hal_slcd_sync.h>
 
 extern struct adc_sync_descriptor ADC_0;
 
-extern struct calendar_descriptor CALENDAR_0;
-
 extern struct i2c_m_sync_desc I2C_0;
 
-extern struct pwm_descriptor PWM_0;
-
-extern struct pwm_descriptor       PWM_1;
 extern struct slcd_sync_descriptor SEGMENT_LCD_0;
 
-void ADC_0_PORT_init(void);
-void ADC_0_CLOCK_init(void);
-void ADC_0_init(void);
-
-void CALENDAR_0_CLOCK_init(void);
-void CALENDAR_0_init(void);
-
 void I2C_0_CLOCK_init(void);
 void I2C_0_init(void);
 void I2C_0_PORT_init(void);
 
 void delay_driver_init(void);
 
-void PWM_0_PORT_init(void);
-void PWM_0_CLOCK_init(void);
-void PWM_0_init(void);
-
-void PWM_1_PORT_init(void);
-void PWM_1_CLOCK_init(void);
-void PWM_1_init(void);
-
 void EXTERNAL_IRQ_0_init(void);
 
 void SEGMENT_LCD_0_init(void);
diff --git a/watch-library/watch/watch.c b/watch-library/watch/watch.c
index 6196b1f3..de7160c5 100644
--- a/watch-library/watch/watch.c
+++ b/watch-library/watch/watch.c
@@ -24,18 +24,6 @@
 
 #include "watch.h"
 
-#include "watch_rtc.c"
-#include "watch_slcd.c"
-#include "watch_extint.c"
-#include "watch_led.c"
-#include "watch_buzzer.c"
-#include "watch_adc.c"
-#include "watch_gpio.c"
-#include "watch_i2c.c"
-#include "watch_uart.c"
-#include "watch_deepsleep.c"
-#include "watch_private.c"
-
 bool battery_is_low = false;
 
 // receives interrupts from MCLK, OSC32KCTRL, OSCCTRL, PAC, PM, SUPC and TAL, whatever that is.
diff --git a/watch-library/watch/watch_adc.c b/watch-library/watch/watch_adc.c
index 490a49b1..90980a88 100644
--- a/watch-library/watch/watch_adc.c
+++ b/watch-library/watch/watch_adc.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_adc.h"
+
 void _watch_sync_adc() {
     while (ADC->SYNCBUSY.reg);
 }
diff --git a/watch-library/watch/watch_adc.h b/watch-library/watch/watch_adc.h
index b49f1301..c9b6ad2a 100644
--- a/watch-library/watch/watch_adc.h
+++ b/watch-library/watch/watch_adc.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_ADC_H_INCLUDED
+#define _WATCH_ADC_H_INCLUDED
 ////< @file watch_adc.h
 
+#include "watch.h"
+
 /** @addtogroup adc Analog Input
   * @brief This section covers functions related to the SAM L22's analog-to-digital converter,
   *        as well as configuring and reading values from the five analog-capable pins on the
@@ -103,3 +107,4 @@ void watch_disable_analog_input(const uint8_t pin);
 void watch_disable_adc();
 
 /// @}
+#endif
diff --git a/watch-library/watch/watch_app.h b/watch-library/watch/watch_app.h
index fd7ea706..00a6a610 100644
--- a/watch-library/watch/watch_app.h
+++ b/watch-library/watch/watch_app.h
@@ -21,6 +21,8 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_APP_H_INCLUDED
+#define _WATCH_APP_H_INCLUDED
 ////< @file watch_app.h
 
 /** @addtogroup app Application Framework
@@ -103,3 +105,4 @@ void app_prepare_for_sleep();
 void app_wake_from_sleep();
 
 /// @}
+#endif
diff --git a/watch-library/watch/watch_buzzer.c b/watch-library/watch/watch_buzzer.c
index 9cb37393..007a44ca 100644
--- a/watch-library/watch/watch_buzzer.c
+++ b/watch-library/watch/watch_buzzer.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_buzzer.h"
+
  inline void watch_enable_buzzer() {
     if (!hri_tcc_get_CTRLA_reg(TCC0, TCC_CTRLA_ENABLE)) {
         _watch_enable_tcc();
diff --git a/watch-library/watch/watch_buzzer.h b/watch-library/watch/watch_buzzer.h
index 995e059a..e15657be 100644
--- a/watch-library/watch/watch_buzzer.h
+++ b/watch-library/watch/watch_buzzer.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_BUZZER_H_INCLUDED
+#define _WATCH_BUZZER_H_INCLUDED
 ////< @file watch_buzzer.h
 
+#include "watch.h"
+
 /** @addtogroup buzzer Buzzer
   * @brief This section covers functions related to the piezo buzzer embedded in the F-91W's back plate.
   */
@@ -157,3 +161,4 @@ void watch_buzzer_play_note(BuzzerNote note, uint16_t duration_ms);
 extern const uint16_t NotePeriods[108];
 
 /// @}
+#endif
diff --git a/watch-library/watch/watch_deepsleep.c b/watch-library/watch/watch_deepsleep.c
index a69ba66c..b7da82ee 100644
--- a/watch-library/watch/watch_deepsleep.c
+++ b/watch-library/watch/watch_deepsleep.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_extint.h"
+
 // this warning only appears when you `make BOARD=OSO-SWAT-A1-02`. it's annoying,
 // but i'd rather have it warn us at build-time than fail silently at run-time.
 // besides, no one but me really has any of these boards anyway.
@@ -29,24 +31,9 @@
 #warning This board revision does not support external wake on BTN_ALARM, so watch_register_extwake_callback will not work with it. Use watch_register_interrupt_callback instead.
 #endif
 
-static void extwake_callback(uint8_t reason);
-ext_irq_cb_t btn_alarm_callback;
-ext_irq_cb_t a2_callback;
-ext_irq_cb_t a4_callback;
-
- static void extwake_callback(uint8_t reason) {
-    if (reason & RTC_TAMPID_TAMPID2) {
-        if (btn_alarm_callback != NULL) btn_alarm_callback();
-    } else if (reason & RTC_TAMPID_TAMPID1) {
-        if (a2_callback != NULL) a2_callback();
-    } else if (reason & RTC_TAMPID_TAMPID0) {
-        if (a4_callback != NULL) a4_callback();
-    }
-}
-
 void watch_register_extwake_callback(uint8_t pin, ext_irq_cb_t callback, bool level) {
     uint32_t pinmux;
-    hri_rtc_tampctrl_reg_t config = hri_rtc_get_TAMPCTRL_reg(RTC, 0xFFFFFFFF);
+    hri_rtc_tampctrl_reg_t config = RTC->MODE2.TAMPCTRL.reg;
 
     switch (pin) {
         case A4:
@@ -84,16 +71,17 @@ void watch_register_extwake_callback(uint8_t pin, ext_irq_cb_t callback, bool le
     gpio_set_pin_function(pin, pinmux);
 
     // disable the RTC
-	if (hri_rtcmode0_get_CTRLA_ENABLE_bit(RTC)) {
-		hri_rtcmode0_clear_CTRLA_ENABLE_bit(RTC);
-		hri_rtcmode0_wait_for_sync(RTC, RTC_MODE0_SYNCBUSY_ENABLE);
-	}
+    RTC->MODE2.CTRLA.bit.ENABLE = 0;
+    while (RTC->MODE2.SYNCBUSY.bit.ENABLE);
+
     // update the configuration
-    hri_rtc_write_TAMPCTRL_reg(RTC, config);
+    RTC->MODE2.TAMPCTRL.reg = config;
     // re-enable the RTC
-    hri_rtcmode0_set_CTRLA_ENABLE_bit(RTC);
+    RTC->MODE2.CTRLA.bit.ENABLE = 1;
 
-    _extwake_register_callback(&CALENDAR_0.device, extwake_callback);
+    NVIC_ClearPendingIRQ(RTC_IRQn);
+    NVIC_EnableIRQ(RTC_IRQn);
+    RTC->MODE2.INTENSET.reg = RTC_MODE2_INTENSET_TAMPER;
 }
 
 void watch_disable_extwake_interrupt(uint8_t pin) {
@@ -176,7 +164,7 @@ void watch_enter_shallow_sleep(char *message) {
     _watch_disable_all_peripherals_except_slcd();
 
     // disable tick interrupt
-    watch_register_tick_callback(NULL);
+    watch_rtc_disable_all_periodic_callbacks();
 
     // disable brownout detector interrupt, which could inadvertently wake us up.
     SUPC->INTENCLR.bit.BOD33DET = 1;
@@ -202,7 +190,7 @@ void watch_enter_deep_sleep() {
     // so let's do it!
     watch_register_extwake_callback(BTN_ALARM, NULL, true);
 
-    watch_register_tick_callback(NULL);
+    watch_rtc_disable_all_periodic_callbacks();
     _watch_disable_all_peripherals_except_slcd();
     slcd_sync_deinit(&SEGMENT_LCD_0);
     hri_mclk_clear_APBCMASK_SLCD_bit(SLCD);
diff --git a/watch-library/watch/watch_deepsleep.h b/watch-library/watch/watch_deepsleep.h
index 1e118929..3dc428d0 100644
--- a/watch-library/watch/watch_deepsleep.h
+++ b/watch-library/watch/watch_deepsleep.h
@@ -21,8 +21,17 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_DEEPSLEEP_H_INCLUDED
+#define _WATCH_DEEPSLEEP_H_INCLUDED
 ////< @file watch_deepsleep.h
 
+#include "watch.h"
+
+// These are declared in watch_rtc.c.
+extern ext_irq_cb_t btn_alarm_callback;
+extern ext_irq_cb_t a2_callback;
+extern ext_irq_cb_t a4_callback;
+
 /** @addtogroup deepsleep Deep Sleep Control
   * @brief This section covers functions related to preparing for and entering BACKUP mode, the
   *        deepest sleep mode available on the SAM L22
@@ -110,3 +119,4 @@ void watch_enter_shallow_sleep(char *message);
   */
 void watch_enter_deep_sleep();
 /// @}
+#endif
diff --git a/watch-library/watch/watch_extint.c b/watch-library/watch/watch_extint.c
index f2bad949..dcaa0d80 100644
--- a/watch-library/watch/watch_extint.c
+++ b/watch-library/watch/watch_extint.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_extint.h"
+
 void watch_enable_external_interrupts() {
     // Configure EIC to use GCLK3 (the 32.768 kHz crystal)
     hri_gclk_write_PCHCTRL_reg(GCLK, EIC_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK3_Val | (1 << GCLK_PCHCTRL_CHEN_Pos));
diff --git a/watch-library/watch/watch_extint.h b/watch-library/watch/watch_extint.h
index 9c810534..758fe8bc 100644
--- a/watch-library/watch/watch_extint.h
+++ b/watch-library/watch/watch_extint.h
@@ -21,8 +21,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_EXTINT_H_INCLUDED
+#define _WATCH_EXTINT_H_INCLUDED
 ////< @file watch_extint.h
 
+#include "watch.h"
 #include "hal_ext_irq.h"
 
 /** @addtogroup buttons Buttons & External Interrupts
@@ -78,3 +81,4 @@ void watch_register_button_callback(const uint8_t pin, ext_irq_cb_t callback);
 __attribute__((deprecated("Use watch_enable_external_interrupts instead")))
 void watch_enable_buttons();
 /// @}
+#endif
diff --git a/watch-library/watch/watch_gpio.c b/watch-library/watch/watch_gpio.c
index a9bc139d..b37d009f 100644
--- a/watch-library/watch/watch_gpio.c
+++ b/watch-library/watch/watch_gpio.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_gpio.h"
+
  void watch_enable_digital_input(const uint8_t pin) {
     gpio_set_pin_direction(pin, GPIO_DIRECTION_IN);
     gpio_set_pin_function(pin, GPIO_PIN_FUNCTION_OFF);
diff --git a/watch-library/watch/watch_gpio.h b/watch-library/watch/watch_gpio.h
index 640686e0..fc43642c 100644
--- a/watch-library/watch/watch_gpio.h
+++ b/watch-library/watch/watch_gpio.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_GPIO_H_INCLUDED
+#define _WATCH_GPIO_H_INCLUDED
 ////< @file watch_gpio.h
 
+#include "watch.h"
+
 /** @addtogroup gpio Digital Input and Output
   * @brief This section covers functions related to general-purpose input and output signals.
   */
@@ -69,3 +73,4 @@ void watch_disable_digital_output(const uint8_t pin);
   */
 void watch_set_pin_level(const uint8_t pin, const bool level);
 /// @}
+#endif
diff --git a/watch-library/watch/watch_i2c.c b/watch-library/watch/watch_i2c.c
index 385d9d08..d2cf474b 100644
--- a/watch-library/watch/watch_i2c.c
+++ b/watch-library/watch/watch_i2c.c
@@ -22,7 +22,9 @@
  * SOFTWARE.
  */
 
- struct io_descriptor *I2C_0_io;
+#include "watch_i2c.h"
+
+struct io_descriptor *I2C_0_io;
 
 void watch_enable_i2c() {
     I2C_0_init();
diff --git a/watch-library/watch/watch_i2c.h b/watch-library/watch/watch_i2c.h
index 7ac05c13..65df49b4 100644
--- a/watch-library/watch/watch_i2c.h
+++ b/watch-library/watch/watch_i2c.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_I2C_H_INCLUDED
+#define _WATCH_I2C_H_INCLUDED
 ////< @file watch_i2c.h
 
+#include "watch.h"
+
 /** @addtogroup i2c I2C Controller Driver
   * @brief This section covers functions related to the SAM L22's built-I2C driver, including
   *        configuring the I2C bus, putting values directly on the bus and reading data from
@@ -99,3 +103,4 @@ uint32_t watch_i2c_read24(int16_t addr, uint8_t reg);
   */
 uint32_t watch_i2c_read32(int16_t addr, uint8_t reg);
 /// @}
+#endif
diff --git a/watch-library/watch/watch_led.c b/watch-library/watch/watch_led.c
index 7b189452..1348c977 100644
--- a/watch-library/watch/watch_led.c
+++ b/watch-library/watch/watch_led.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_led.h"
+
 void watch_enable_leds() {
     if (!hri_tcc_get_CTRLA_reg(TCC0, TCC_CTRLA_ENABLE)) {
         _watch_enable_tcc();
diff --git a/watch-library/watch/watch_led.h b/watch-library/watch/watch_led.h
index 0927e716..2b9dead0 100644
--- a/watch-library/watch/watch_led.h
+++ b/watch-library/watch/watch_led.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_LED_H_INCLUDED
+#define _WATCH_LED_H_INCLUDED
 ////< @file watch_led.h
 
+#include "watch.h"
+
 /** @addtogroup led LED Control
   * @brief This section covers functions related to the bi-color red/green LED mounted behind the LCD.
   * @details The SAM L22 is an exceedingly power efficient chip, whereas the LED's are relatively power-
@@ -86,3 +90,4 @@ void watch_enable_led(bool unused);
 __attribute__((deprecated("Use watch_disable_leds instead")))
 void watch_disable_led(bool unused);
 /// @}
+#endif
diff --git a/watch-library/watch/watch_private.c b/watch-library/watch/watch_private.c
index bdf6b78a..270208dc 100644
--- a/watch-library/watch/watch_private.c
+++ b/watch-library/watch/watch_private.c
@@ -22,6 +22,7 @@
  * SOFTWARE.
  */
 
+#include "watch_private.h"
 #include "tusb.h"
 
 void _watch_init() {
@@ -56,8 +57,7 @@ void _watch_init() {
     SUPC->BOD33.bit.ENABLE = 1;
 
     // External wake depends on RTC; calendar is a required module.
-    CALENDAR_0_init();
-    calendar_enable(&CALENDAR_0);
+    _watch_rtc_init();
 
     // set up state
     btn_alarm_callback = NULL;
diff --git a/watch-library/watch/watch_private.h b/watch-library/watch/watch_private.h
index abee085a..8045e438 100644
--- a/watch-library/watch/watch_private.h
+++ b/watch-library/watch/watch_private.h
@@ -21,10 +21,17 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_PRIVATE_H_INCLUDED
+#define _WATCH_PRIVATE_H_INCLUDED
+
+#include "watch.h"
 
 /// Called by main.c while setting up the app. You should not call this from your app.
 void _watch_init();
 
+/// Initializes the real-time clock peripheral.
+void _watch_rtc_init();
+
 /// Called by buzzer and LED setup functions. You should not call this from your app.
 void _watch_enable_tcc();
 
@@ -33,3 +40,4 @@ void _watch_disable_tcc();
 
 /// Called by main.c if plugged in to USB. You should not call this from your app.
 void _watch_enable_usb();
+#endif
diff --git a/watch-library/watch/watch_rtc.c b/watch-library/watch/watch_rtc.c
index 2d6d598f..a50da7c4 100644
--- a/watch-library/watch/watch_rtc.c
+++ b/watch-library/watch/watch_rtc.c
@@ -22,19 +22,174 @@
  * SOFTWARE.
  */
 
- bool _watch_rtc_is_enabled() {
-    return RTC->MODE0.CTRLA.bit.ENABLE;
+#include "watch_rtc.h"
+
+ext_irq_cb_t tick_callbacks[8];
+ext_irq_cb_t alarm_callback;
+ext_irq_cb_t btn_alarm_callback;
+ext_irq_cb_t a2_callback;
+ext_irq_cb_t a4_callback;
+
+bool _watch_rtc_is_enabled() {
+    return RTC->MODE2.CTRLA.bit.ENABLE;
+}
+
+void _sync_rtc() {
+    while (RTC->MODE2.SYNCBUSY.reg);
 }
 
+void _watch_rtc_init() {
+    MCLK->APBAMASK.reg |= MCLK_APBAMASK_RTC;
+
+    if (_watch_rtc_is_enabled()) return; // don't reset the RTC if it's already set up.
+
+    RTC->MODE2.CTRLA.bit.ENABLE = 0;
+    _sync_rtc();
+
+    RTC->MODE2.CTRLA.bit.SWRST = 1;
+    _sync_rtc();
+
+    RTC->MODE2.CTRLA.bit.MODE = RTC_MODE2_CTRLA_MODE_CLOCK_Val;
+    RTC->MODE2.CTRLA.bit.PRESCALER = RTC_MODE2_CTRLA_PRESCALER_DIV1024_Val;
+    RTC->MODE2.CTRLA.bit.CLOCKSYNC = 1;
+    RTC->MODE2.CTRLA.bit.ENABLE = 1;
+    _sync_rtc();
+}
+
+void watch_rtc_set_date_time(watch_date_time date_time) {
+    RTC->MODE2.CLOCK.reg = date_time.reg;
+    _sync_rtc();
+}
+
+watch_date_time watch_rtc_get_date_time() {
+    watch_date_time retval;
+
+    _sync_rtc();
+    retval.reg = RTC->MODE2.CLOCK.reg;
+
+    return retval;
+}
+
+void watch_rtc_register_tick_callback(ext_irq_cb_t callback) {
+    watch_rtc_register_periodic_callback(callback, 1);
+}
+
+void watch_rtc_disable_tick_callback() {
+    watch_rtc_disable_periodic_callback(1);
+}
+
+void watch_rtc_register_periodic_callback(ext_irq_cb_t callback, uint8_t frequency) {
+    // we told them, it has to be a power of 2.
+    if (__builtin_popcount(frequency) != 1) return;
+
+    // this left-justifies the period in a 32-bit integer.
+    uint32_t tmp = frequency << 24;
+    // now we can count the leading zeroes to get the value we need.
+    // 0x01 (1 Hz) will have 7 leading zeros for PER7. 0xF0 (128 Hz) will have no leading zeroes for PER0.
+    uint8_t per_n = __builtin_clz(tmp);
+
+    // this also maps nicely to an index for our list of tick callbacks.
+    tick_callbacks[per_n] = callback;
+
+    NVIC_ClearPendingIRQ(RTC_IRQn);
+    NVIC_EnableIRQ(RTC_IRQn);
+    RTC->MODE2.INTENSET.reg = 1 << per_n;
+}
+
+void watch_rtc_disable_periodic_callback(uint8_t frequency) {
+    if (__builtin_popcount(frequency) != 1) return;
+    uint8_t per_n = __builtin_clz(frequency << 24);
+    RTC->MODE2.INTENCLR.reg = 1 << per_n;
+}
+
+void watch_rtc_disable_all_periodic_callbacks() {
+    RTC->MODE2.INTENCLR.reg = 0xFF;
+}
+
+void watch_rtc_register_alarm_callback(ext_irq_cb_t callback, watch_date_time alarm_time, watch_rtc_alarm_match mask) {
+    RTC->MODE2.Mode2Alarm[0].ALARM.reg = alarm_time.reg;
+    RTC->MODE2.Mode2Alarm[0].MASK.reg = mask;
+    RTC->MODE2.INTENSET.reg = RTC_MODE2_INTENSET_ALARM0;
+    alarm_callback = callback;
+    NVIC_ClearPendingIRQ(RTC_IRQn);
+    NVIC_EnableIRQ(RTC_IRQn);
+    RTC->MODE2.INTENSET.reg = RTC_MODE2_INTENSET_ALARM0;
+}
+
+void watch_rtc_disable_alarm_callback() {
+    RTC->MODE2.INTENCLR.reg = RTC_MODE2_INTENCLR_ALARM0;
+}
+
+void RTC_Handler(void) {
+    uint16_t interrupt_status = RTC->MODE2.INTFLAG.reg;
+    uint16_t interrupt_enabled = RTC->MODE2.INTENSET.reg;
+
+    if ((interrupt_status & interrupt_enabled) & RTC_MODE2_INTFLAG_PER_Msk) {
+        // handle the tick callback first, it's what we do the most.
+        // start from PER7, the 1 Hz tick.
+        for(int8_t i = 7; i >= 0; i--) {
+            if ((interrupt_status & interrupt_enabled) & (1 << i)) {
+                if (tick_callbacks[i] != NULL) {
+                    tick_callbacks[i]();
+                }
+                RTC->MODE2.INTFLAG.reg = 1 << i;
+                break;
+            }
+        }
+    } else if ((interrupt_status & interrupt_enabled) & RTC_MODE2_INTFLAG_TAMPER) {
+        // handle the extwake interrupts next.
+        uint8_t reason = RTC->MODE2.TAMPID.reg;
+        if (reason & RTC_TAMPID_TAMPID2) {
+            if (btn_alarm_callback != NULL) btn_alarm_callback();
+        } else if (reason & RTC_TAMPID_TAMPID1) {
+            if (a2_callback != NULL) a2_callback();
+        } else if (reason & RTC_TAMPID_TAMPID0) {
+            if (a4_callback != NULL) a4_callback();
+        }
+        RTC->MODE2.TAMPID.reg = reason;
+        RTC->MODE2.INTFLAG.reg = RTC_MODE2_INTFLAG_TAMPER;
+    } else if ((interrupt_status & interrupt_enabled) & RTC_MODE2_INTFLAG_ALARM0) {
+        // finally handle the alarm.
+        if (alarm_callback != NULL) {
+            alarm_callback();
+        }
+        RTC->MODE2.INTFLAG.reg = RTC_MODE2_INTFLAG_ALARM0;
+    }
+}
+
+///////////////////////
+// Deprecated functions
+
 void watch_set_date_time(struct calendar_date_time date_time) {
-    calendar_set_date(&CALENDAR_0, &date_time.date);
-    calendar_set_time(&CALENDAR_0, &date_time.time);
+    RTC_MODE2_CLOCK_Type val;
+
+    val.bit.SECOND = date_time.time.sec;
+    val.bit.MINUTE = date_time.time.min;
+    val.bit.HOUR = date_time.time.hour;
+    val.bit.DAY = date_time.date.day;
+    val.bit.MONTH = date_time.date.month;
+    val.bit.YEAR = (uint8_t)(date_time.date.year - WATCH_RTC_REFERENCE_YEAR);
+
+    RTC->MODE2.CLOCK.reg = val.reg;
+
+    _sync_rtc();
 }
 
 void watch_get_date_time(struct calendar_date_time *date_time) {
-    calendar_get_date_time(&CALENDAR_0, date_time);
+    _sync_rtc();
+    RTC_MODE2_CLOCK_Type val = RTC->MODE2.CLOCK;
+
+    date_time->time.sec = val.bit.SECOND;
+    date_time->time.min = val.bit.MINUTE;
+    date_time->time.hour = val.bit.HOUR;
+    date_time->date.day = val.bit.DAY;
+    date_time->date.month = val.bit.MONTH;
+    date_time->date.year = val.bit.YEAR + WATCH_RTC_REFERENCE_YEAR;
 }
 
 void watch_register_tick_callback(ext_irq_cb_t callback) {
-    _prescaler_register_callback(&CALENDAR_0.device, callback);
+    tick_callbacks[7] = callback;
+    NVIC_ClearPendingIRQ(RTC_IRQn);
+    NVIC_EnableIRQ(RTC_IRQn);
+    RTC->MODE2.INTENSET.reg = RTC_MODE2_INTENSET_PER7;
 }
diff --git a/watch-library/watch/watch_rtc.h b/watch-library/watch/watch_rtc.h
index c685ac26..1776a712 100644
--- a/watch-library/watch/watch_rtc.h
+++ b/watch-library/watch/watch_rtc.h
@@ -21,8 +21,11 @@
  * 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
@@ -35,24 +38,127 @@
   *          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 sbould always return true.
+  * You may call this function, but outside of app_init, it should always return true.
   */
 bool _watch_rtc_is_enabled();
 
+/** @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();
+
+/** @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 both shallow and deep 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();
+
+/** @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();
+
+/** @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 all periodic callbacks, including the once-per-second tick callback.
+  */
+void watch_rtc_disable_all_periodic_callbacks();
+
 /** @brief Sets the system date and time.
   * @param date_time A struct representing the date and time you wish to set.
   */
+__attribute__((deprecated("Use watch_rtc_set_date_time function instead")))
 void watch_set_date_time(struct calendar_date_time date_time);
 
 /** @brief Returns the system date and time in the provided struct.
-  * @param date_time A pointer to a calendar_date_time struct.
-                     It will be populated with the correct date and time on return.
+  * @param date_time A pointer to a calendar_date_time struct. It will have with the correct date and time on return.
   */
+__attribute__((deprecated("Use the watch_rtc_get_date_time function instead")))
 void watch_get_date_time(struct calendar_date_time *date_time);
 
 /** @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.
+  * @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.
   */
+__attribute__((deprecated("Use the watch_rtc_register_tick_callback function instead")))
 void watch_register_tick_callback(ext_irq_cb_t callback);
+
 /// @}
+#endif
diff --git a/watch-library/watch/watch_slcd.c b/watch-library/watch/watch_slcd.c
index 7210713a..ba9d12b2 100644
--- a/watch-library/watch/watch_slcd.c
+++ b/watch-library/watch/watch_slcd.c
@@ -22,6 +22,8 @@
  * SOFTWARE.
  */
 
+#include "watch_slcd.h"
+
  //////////////////////////////////////////////////////////////////////////////////////////
 // Segmented Display
 
diff --git a/watch-library/watch/watch_slcd.h b/watch-library/watch/watch_slcd.h
index efef99ac..4f5a617c 100644
--- a/watch-library/watch/watch_slcd.h
+++ b/watch-library/watch/watch_slcd.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_SLCD_H_INCLUDED
+#define _WATCH_SLCD_H_INCLUDED
 ////< @file watch_slcd.h
 
+#include "watch.h"
+
 /** @addtogroup slcd Segment LCD Display
   * @brief This section covers functions related to the Segment LCD display driver, which is responsible
   *        for displaying strings of characters and indicators on the main watch display.
@@ -100,3 +104,4 @@ void watch_clear_indicator(WatchIndicatorSegment indicator);
 void watch_clear_all_indicators();
 
 /// @}
+#endif
diff --git a/watch-library/watch/watch_uart.c b/watch-library/watch/watch_uart.c
index 3d97803d..d35533d0 100644
--- a/watch-library/watch/watch_uart.c
+++ b/watch-library/watch/watch_uart.c
@@ -50,6 +50,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include "watch_uart.h"
 #include "peripheral_clk_config.h"
 
 void watch_enable_debug_uart(uint32_t baud) {
diff --git a/watch-library/watch/watch_uart.h b/watch-library/watch/watch_uart.h
index 3c4f7aef..3e98bd35 100644
--- a/watch-library/watch/watch_uart.h
+++ b/watch-library/watch/watch_uart.h
@@ -21,8 +21,12 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+#ifndef _WATCH_UART_H_INCLUDED
+#define _WATCH_UART_H_INCLUDED
 ////< @file watch_uart.h
 
+#include "watch.h"
+
 /** @addtogroup debug Debug UART
   * @brief This section covers functions related to the debug UART, available on
   *        pin D1 of the 9-pin connector.
@@ -51,3 +55,4 @@ void watch_debug_putc(char c);
 __attribute__((deprecated("Use printf to log debug messages over USB.")))
 void watch_debug_puts(char *s);
 /// @}
+#endif