Add stock stopwatch face (#140)

* buzzer sequences: first draft, does not work on hardware yet (but in simulator)

* buzzer sequences: add changes to movement.c

* buzzer sequences: add demo face to Makefile

* buzzer sequences: fix problem of interrupted sounds. Add logic for repeating sub sequences. Tidy up (move logic to watch_buzzer files, remove buzzer_demo_face)

* buzzer sequences: tidy up even more

* buzzer sequences: disable registering a 32 Hz tick callback for watch faces, so it will be used exclusively by the buzzer sequences functionality

* buzzer sequences: add callback slot functionality to watch_rtc and make watch_buzzer use it. Switch internal buzzer sequences tick frequency to 64 Hz. Revert changes to movement.c

* buzzer sequences: fix parameter sanity check in watch_rtc code

* stock stopwatch: first fully functional implementation

* stock stopwatch: fix typo in comment

* stock stopwatch: handle resuming from deep sleep mode properly

* buzzer sequences/watch_rtc: optimize calling tick callbacks in RTC_Handler

* buzzer sequences/watch_rtc: fix error in calling callback functions

* stock stopwatch: implement workaround for sleep mode

* stock stopwatch: merge current main into stock-stopwatch

* stock stopwatch: use TC counters as source for callbacks

* stock-stopwatch: revert unnecessary changes to watch_buzzer

Co-authored-by: joeycastillo <joeycastillo@utexas.edu>

5 files changed, 387 insertions, 1 deletions

diff --git a/movement/make/Makefile b/movement/make/Makefile
index 9def50de..40f798c6 100644
--- a/movement/make/Makefile
+++ b/movement/make/Makefile
@@ -76,6 +76,7 @@ SRCS += \
   ../watch_faces/complication/alarm_face.c \
   ../watch_faces/complication/ratemeter_face.c \
   ../watch_faces/complication/rpn_calculator_alt_face.c \
+  ../watch_faces/complication/stock_stopwatch_face.c \
 # New watch faces go above this line.
 
 # Leave this line at the bottom of the file; it has all the targets for making your project.
diff --git a/movement/movement.h b/movement/movement.h
index 9dc5fe82..7b5c4647 100644
--- a/movement/movement.h
+++ b/movement/movement.h
@@ -61,7 +61,7 @@ typedef union {
         // altimeter to display feet or meters as easily as it tells a thermometer to display degrees in F or C.
         bool clock_mode_24h : 1;            // indicates whether clock should use 12 or 24 hour mode.
         bool use_imperial_units : 1;        // indicates whether to use metric units (the default) or imperial.
-        bool alarm_enabled : 1;             // indicates wheter there is at least one alarm enabled.
+        bool alarm_enabled : 1;             // indicates whether there is at least one alarm enabled.
         uint8_t reserved : 6;               // room for more preferences if needed.
     } bit;
     uint32_t reg;
diff --git a/movement/movement_faces.h b/movement/movement_faces.h
index 98d0a5c5..2e6c4c33 100644
--- a/movement/movement_faces.h
+++ b/movement/movement_faces.h
@@ -61,6 +61,7 @@
 #include "ratemeter_face.h"
 #include "rpn_calculator_alt_face.h"
 #include "weeknumber_clock_face.h"
+#include "stock_stopwatch_face.h"
 // New includes go above this line.
 
 #endif // MOVEMENT_FACES_H_
diff --git a/movement/watch_faces/complication/stock_stopwatch_face.c b/movement/watch_faces/complication/stock_stopwatch_face.c
new file mode 100644
index 00000000..1164eb9a
--- /dev/null
+++ b/movement/watch_faces/complication/stock_stopwatch_face.c
@@ -0,0 +1,326 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2022 Andreas Nebinger
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include "stock_stopwatch_face.h"
+#include "watch.h"
+#include "watch_utility.h"
+#include "watch_rtc.h"
+
+/*
+    This watch face implements the original F-91W stopwatch functionality
+    including counting hundredths of seconds and lap timing. There are two
+    improvements compared to the functionality of the original: 
+    1. When reaching 59:59 the counter does not simply jump back to zero,
+       but keeps track of hours in the upper right hand corner. (Up to 24h)
+    2. Long pressing the light button toggles the led behaviour: it either
+       turns on on each button press or it doesn't.
+*/
+
+#if __EMSCRIPTEN__
+#include <emscripten.h>
+#include <emscripten/html5.h>
+#else
+#include "../../../watch-library/hardware/include/saml22j18a.h"
+#include "../../../watch-library/hardware/include/component/tc.h"
+#include "../../../watch-library/hardware/hri/hri_tc_l22.h"
+#endif
+
+// distant future for background task: January 1, 2083
+static const watch_date_time distant_future = {
+    .unit = {0, 0, 0, 1, 1, 63}
+};
+
+static uint32_t _ticks;
+static uint32_t _lap_ticks;
+static uint8_t _blink_ticks;
+static uint32_t _old_seconds;
+static uint8_t _old_minutes;
+static uint8_t _hours;
+static bool _colon;
+static bool _is_running;
+
+#if __EMSCRIPTEN__
+
+static long _em_interval_id = 0;
+
+void em_cb_handler(void *userData) {
+    // interrupt handler for emscripten 128 Hz callbacks
+    (void) userData;
+    _ticks++;
+}
+
+static void _cb_initialize() { }
+
+static inline void _cb_stop() {
+    emscripten_clear_interval(_em_interval_id);
+    _em_interval_id = 0;
+    _is_running = false;
+}
+
+static inline void _cb_start() {
+    // initiate 128 hz callback
+    _em_interval_id = emscripten_set_interval(em_cb_handler, (double)(1000/128), (void *)NULL);
+}
+
+#else
+
+static inline void _cb_start() {
+    // start the TC2 timer
+    hri_tc_set_CTRLA_ENABLE_bit(TC2);
+    _is_running = true;
+}
+
+static inline void _cb_stop() {
+    // stop the TC2 timer
+    hri_tc_clear_CTRLA_ENABLE_bit(TC2);
+    _is_running = false;
+}
+
+static void _cb_initialize() {
+    // setup and initialize TC2 for a 64 Hz interrupt
+    hri_mclk_set_APBCMASK_TC2_bit(MCLK);
+    hri_gclk_write_PCHCTRL_reg(GCLK, TC2_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK3 | GCLK_PCHCTRL_CHEN);
+    _cb_stop();
+    hri_tc_write_CTRLA_reg(TC2, TC_CTRLA_SWRST);
+    hri_tc_wait_for_sync(TC2, TC_SYNCBUSY_SWRST);
+    hri_tc_write_CTRLA_reg(TC2, TC_CTRLA_PRESCALER_DIV64 | // 32 Khz divided by 64 divided by 4 results in a 128 Hz interrupt
+                           TC_CTRLA_MODE_COUNT8 | 
+                           TC_CTRLA_RUNSTDBY);
+    hri_tccount8_write_PER_reg(TC2, 3);
+    hri_tc_set_INTEN_OVF_bit(TC2);
+    NVIC_ClearPendingIRQ(TC2_IRQn);
+    NVIC_EnableIRQ (TC2_IRQn);
+}
+
+void TC2_Handler(void) {
+    // interrupt handler for TC2 (globally!)
+    _ticks++;
+    TC2->COUNT8.INTFLAG.reg |= TC_INTFLAG_OVF;
+}
+
+#endif
+
+static inline void _button_beep(movement_settings_t *settings) {
+    // play a beep as confirmation for a button press (if applicable)
+    if (settings->bit.button_should_sound) watch_buzzer_play_note(BUZZER_NOTE_C7, 50);
+}
+
+/// @brief Display minutes, seconds and fractions derived from 128 Hz tick counter
+///        on the lcd.
+/// @param ticks
+static void _display_ticks(uint32_t ticks) {
+    char buf[14];
+    uint8_t sec_100 = (ticks & 0x7F) * 100 / 128;
+    uint32_t seconds = ticks >> 7;
+    uint32_t minutes = seconds / 60;
+    if (_hours)
+        sprintf(buf, "%2u%02lu%02lu%02u", _hours, minutes, (seconds % 60), sec_100);
+    else
+        sprintf(buf, "  %02lu%02lu%02u", minutes, (seconds % 60), sec_100);
+    watch_display_string(buf, 2);
+}
+
+/// @brief Displays the current stopwatch time on the LCD (more optimized than _display_ticks())
+static void _draw() {
+    if (_lap_ticks == 0) {
+        char buf[14];
+        uint8_t sec_100 = (_ticks & 0x7F) * 100 / 128;
+        if (_is_running) {
+            uint32_t seconds = _ticks >> 7;
+            if (seconds != _old_seconds) {
+                // seconds have changed
+                _old_seconds = seconds;
+                uint8_t minutes = seconds / 60;
+                seconds %= 60;
+                if (minutes != _old_minutes) {
+                    // minutes have changed, draw everything
+                    _old_minutes = minutes;
+                    minutes %= 60;
+                    if (_hours)
+                        // with hour indicator
+                        sprintf(buf, "%2u%02u%02lu%02u", _hours, minutes, seconds, sec_100);
+                    else
+                        // no hour indicator
+                        sprintf(buf, "  %02u%02lu%02u", minutes, seconds, sec_100);
+                    watch_display_string(buf, 2);
+                } else {
+                    // just draw seconds
+                    sprintf(buf, "%02lu%02u", seconds, sec_100);
+                    watch_display_string(buf, 6);
+                }
+            } else {
+                // only draw 100ths of seconds
+                sprintf(buf, "%02u", sec_100);
+                watch_display_string(buf, 8);
+            }
+        } else {
+            _display_ticks(_ticks);
+        }
+    }
+    if (_is_running) {
+        // blink the colon every half second
+        uint8_t blink_ticks = ((_ticks >> 6) & 1);
+        if (blink_ticks != _blink_ticks) {
+            _blink_ticks = blink_ticks;
+            _colon = !_colon;
+            if (_colon) watch_set_colon();
+            else watch_clear_colon();
+        }
+    }
+}
+
+static inline void _update_lap_indicator() {
+    if (_lap_ticks) watch_set_indicator(WATCH_INDICATOR_LAP);
+    else  watch_clear_indicator(WATCH_INDICATOR_LAP);
+}
+
+static inline void _set_colon() {
+    watch_set_colon();
+    _colon = true;
+}
+
+void stock_stopwatch_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
+    (void) settings;
+    (void) watch_face_index;
+    if (*context_ptr == NULL) {
+        *context_ptr = malloc(sizeof(stock_stopwatch_state_t));
+        memset(*context_ptr, 0, sizeof(stock_stopwatch_state_t));
+        stock_stopwatch_state_t *state = (stock_stopwatch_state_t *)*context_ptr;
+        _ticks = _lap_ticks = _blink_ticks = _old_minutes = _old_seconds = _hours = 0;
+    _is_running = _colon = false;
+        state->light_on_button = true;
+    }
+    if (!_is_running) {
+        // prepare the 128 Hz callback source
+        _cb_initialize();
+    }
+}
+
+void stock_stopwatch_face_activate(movement_settings_t *settings, void *context) {
+    (void) settings;
+    (void) context;
+    if (_is_running) {
+        // The background task will keep the watch from entering low energy mode while the stopwatch is on screen.
+        movement_schedule_background_task(distant_future);
+    }
+}
+
+bool stock_stopwatch_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
+    stock_stopwatch_state_t *state = (stock_stopwatch_state_t *)context;
+
+    // handle overflow of fast ticks
+    while (_ticks >= (128 * 60 * 60)) {
+        _ticks -= (128 * 60 * 60);
+        _hours++;
+        if (_hours >= 24) _hours -= 24;
+        // initiate a re-draw
+        _old_minutes = 59;
+    }
+
+    switch (event.event_type) {
+        case EVENT_ACTIVATE:
+            _set_colon();
+            watch_display_string("ST  ", 0);
+            _update_lap_indicator();
+            if (_is_running) movement_request_tick_frequency(16);
+            _display_ticks(_lap_ticks ? _lap_ticks : _ticks);
+            break;
+        case EVENT_TICK:
+            _draw();
+            break;
+        case EVENT_MODE_BUTTON_UP:
+            movement_move_to_next_face();
+            break;
+        case EVENT_LIGHT_LONG_PRESS:
+            // kind od hidden feature: long press toggles light on or off
+            state->light_on_button = !state->light_on_button;
+            if (state->light_on_button) movement_illuminate_led();
+            else watch_set_led_off();
+            break;
+        case EVENT_ALARM_BUTTON_DOWN:
+            _is_running = !_is_running;
+            if (_is_running) {
+                // start or continue stopwatch
+                movement_request_tick_frequency(16);
+                // register 128 hz callback for time measuring
+                _cb_start();
+                // schedule the keepalive task when running
+                movement_schedule_background_task(distant_future);
+            } else {
+                // stop the stopwatch
+                _cb_stop();
+                movement_request_tick_frequency(1);
+                _set_colon();
+                // cancel the keepalive task
+                movement_cancel_background_task();
+            }
+            _draw();
+            _button_beep(settings);
+            break;
+        case EVENT_LIGHT_BUTTON_DOWN:
+            if (state->light_on_button) movement_illuminate_led();
+            if (_is_running) {
+                if (_lap_ticks) {
+                    // clear lap and continue running
+                    _lap_ticks = 0;
+                    movement_request_tick_frequency(16);
+                } else {
+                    // set lap ticks and stop updating the display
+                    _lap_ticks = _ticks;
+                    movement_request_tick_frequency(2);
+                    _set_colon();
+                }
+            } else {
+                if (_lap_ticks) {
+                    // clear lap and show running stopwatch
+                    _lap_ticks = 0;
+                } else if (_ticks) {
+                    // reset stopwatch
+                    _ticks = _lap_ticks = _blink_ticks = _old_minutes = _old_seconds = _hours = 0;
+                    _button_beep(settings);
+                }
+            }
+            _display_ticks(_ticks);
+            _update_lap_indicator();
+            break;
+        case EVENT_TIMEOUT:
+            if (!_is_running) movement_move_to_face(0);
+            break;
+        case EVENT_LOW_ENERGY_UPDATE:
+            _draw();
+            break;
+        default:
+            break;
+    }
+    return true;
+}
+
+void stock_stopwatch_face_resign(movement_settings_t *settings, void *context) {
+    (void) settings;
+    (void) context;
+    // cancel the keepalive task
+    movement_cancel_background_task();
+}
\ No newline at end of file
diff --git a/movement/watch_faces/complication/stock_stopwatch_face.h b/movement/watch_faces/complication/stock_stopwatch_face.h
new file mode 100644
index 00000000..d8880df7
--- /dev/null
+++ b/movement/watch_faces/complication/stock_stopwatch_face.h
@@ -0,0 +1,58 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2022 Andreas Nebinger
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef STOCK_STOPWATCH_FACE_H_
+#define STOCK_STOPWATCH_FACE_H_
+
+#include "movement.h"
+
+// This watch face relies heavily on static vars in stock_stopwatch.c.
+// The disadvantage is that you cannot use more than one instance of this watch face on
+// your custom firmware - but then again, who would want that? The advantage is that accessing
+// vars is more direct and faster, and we can save some precious cpu cycles  :-) 
+
+typedef struct {
+    bool light_on_button;   // determines whether the light button actually triggers the led
+} stock_stopwatch_state_t;
+
+void stock_stopwatch_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
+void stock_stopwatch_face_activate(movement_settings_t *settings, void *context);
+bool stock_stopwatch_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
+void stock_stopwatch_face_resign(movement_settings_t *settings, void *context);
+
+#if __EMSCRIPTEN__
+void em_cb_handler(void *userData);
+#else
+void TC2_Handler(void);
+#endif
+
+#define stock_stopwatch_face ((const watch_face_t){ \
+    stock_stopwatch_face_setup, \
+    stock_stopwatch_face_activate, \
+    stock_stopwatch_face_loop, \
+    stock_stopwatch_face_resign, \
+    NULL, \
+})
+
+#endif // STOCK_STOPWATCH_FACE_H_