Merge branch 'main' of https://github.com/joeycastillo/Sensor-Watch into main

51 files changed, 349 insertions, 72 deletions

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 00000000..1eab21fc
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,27 @@
+name: Build
+
+on:
+  pull_request:
+  push:
+    branches-ignore:
+      - gh-pages
+
+jobs: 
+  build:
+    container:
+      image: ghcr.io/armmbed/mbed-os-env:latest
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Compile starter-project app
+        run: make
+        working-directory: 'apps/starter-project'
+      - name: Compile accelerometer-test app
+        run: make
+        working-directory: 'apps/accelerometer-test'
+      - name: Upload UF2
+        uses: actions/upload-artifact@v2
+        with:
+          name: watch.uf2
+          path: apps/**/build/watch.uf2
diff --git a/.github/workflows/gh-pages.yml b/.github/workflows/gh-pages.yml
new file mode 100644
index 00000000..cab1c2d1
--- /dev/null
+++ b/.github/workflows/gh-pages.yml
@@ -0,0 +1,21 @@
+name: GitHub Pages
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  gh-pages:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Doxygen Action
+        uses: mattnotmitt/doxygen-action@v1
+      - name: Deploy
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_branch: gh-pages
+          publish_dir: docs/
diff --git a/.gitignore b/.gitignore
index 4c97e2d4..1100e911 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,17 +1,19 @@
-.DS_Store
-*.s#*
+**/build/
 *.b#*
-*.pro
-*.job
-
 *.bin
+*.d
 *.elf
 *.hex
+*.job
 *.lss
 *.map
+*.o
+*.pro
+*.s#*
 *.uf2
 *srec
-*.o
-*.d
+.DS_Store
+.idea/
 .vs
 .vscode
+docs/
\ No newline at end of file
diff --git a/Doxyfile b/Doxyfile
index da710195..7f04a047 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -8,7 +8,7 @@ PROJECT_NAME           = "Sensor Watch"
 PROJECT_NUMBER         = "0.0.0"
 PROJECT_BRIEF          = "A board replacement for the classic Casio F-91W wristwatch, powered by a Microchip SAM L22 microcontroller."
 PROJECT_LOGO           =
-OUTPUT_DIRECTORY       = "../Sensor-Watch-Documentation"
+OUTPUT_DIRECTORY       = "."
 CREATE_SUBDIRS         = NO
 ALLOW_UNICODE_NAMES    = NO
 OUTPUT_LANGUAGE        = English
diff --git a/apps/accelerometer-test/make/Makefile b/apps/accelerometer-test/Makefile
index c66ad20c..5534c178 100755
--- a/apps/accelerometer-test/make/Makefile
+++ b/apps/accelerometer-test/Makefile
@@ -1,10 +1,10 @@
-TOP = ../../..
+TOP = ../..
 include $(TOP)/make.mk
 
 INCLUDES += \
-  -I../
+  -I./
 
 SRCS += \
-  ../app.c
+  ./app.c
 
 include $(TOP)/rules.mk
diff --git a/apps/accelerometer-test/make/.gitignore b/apps/accelerometer-test/make/.gitignore
deleted file mode 100755
index 567609b1..00000000
--- a/apps/accelerometer-test/make/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build/
diff --git a/apps/beats-time/make/.gitignore b/apps/beats-time/make/.gitignore
deleted file mode 100755
index 3722ac63..00000000
--- a/apps/beats-time/make/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build/

diff --git a/apps/buzzer-test/make/.gitignore b/apps/buzzer-test/make/.gitignore
deleted file mode 100755
index 3722ac63..00000000
--- a/apps/buzzer-test/make/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build/

diff --git a/apps/spi-test/make/.gitignore b/apps/spi-test/make/.gitignore
deleted file mode 100755
index 3722ac63..00000000
--- a/apps/spi-test/make/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build/

diff --git a/apps/starter-project/make/Makefile b/apps/starter-project/Makefile
index 09a59a05..7cb3c48d 100755
--- a/apps/starter-project/make/Makefile
+++ b/apps/starter-project/Makefile
@@ -1,26 +1,26 @@
 # Leave these lines at the top of the file.
 # TOP should get us to the root of the project...
-TOP = ../../..
+TOP = ../..
 # ...and make.mk has all the watch library sources and includes.
 include $(TOP)/make.mk
 
-# If you add any other subdirectories with header files you wish to include, add them after ../
+# If you add any other subdirectories with header files you wish to include, add them after ./
 # Note that you will need to add a backslash at the end of any line you wish to continue, i.e.
 # INCLUDES += \
-#   -I../ \
-#   -I../drivers/ \
-#   -I../utils/
+#   -I./ \
+#   -I drivers/ \
+#   -I utils/
 INCLUDES += \
-  -I../ \
+  -I./ \
 
-# If you add any other source files you wish to compile, add them after ../app.c
+# If you add any other source files you wish to compile, add them after app.c
 # Note that you will need to add a backslash at the end of any line you wish to continue, i.e.
 # SRCS += \
-#   ../app.c \
-#   ../drivers/bmp280.c \
-#   ../utils/temperature.c
+#   ./app.c \
+#   ./drivers/bmp280.c \
+#   ./utils/temperature.c
 SRCS += \
-  ../app.c \
+  ./app.c \
 
 # Leave this line at the bottom of the file; rules.mk has all the targets for making your project.
 include $(TOP)/rules.mk
diff --git a/apps/starter-project/make/.gitignore b/apps/starter-project/make/.gitignore
deleted file mode 100755
index 3722ac63..00000000
--- a/apps/starter-project/make/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build/

diff --git a/make.mk b/make.mk
index f6a37c7e..f1301733 100644
--- a/make.mk
+++ b/make.mk
@@ -20,7 +20,8 @@ else
   MKDIR = mkdir
 endif
 
-CFLAGS += -W -Wall --std=gnu99 -Os
+CFLAGS += -W -Wall -Wextra -Wmissing-prototypes -Wmissing-declarations
+CFLAGS += --std=gnu99 -Os
 CFLAGS += -fno-diagnostics-show-caret
 CFLAGS += -fdata-sections -ffunction-sections
 CFLAGS += -funsigned-char -funsigned-bitfields
diff --git a/movement/README.md b/movement/README.md
index f5b9cb15..66c1f890 100644
--- a/movement/README.md
+++ b/movement/README.md
@@ -91,7 +91,7 @@ typedef struct {
 Finally, we define the four required functions, and define the watch face struct that users will use to add the face to their watch:
 
 ```c
-void pulsometer_face_setup(movement_settings_t *settings, void ** context_ptr);
+void pulsometer_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void pulsometer_face_activate(movement_settings_t *settings, void *context);
 bool pulsometer_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void pulsometer_face_resign(movement_settings_t *settings, void *context);
@@ -119,7 +119,7 @@ These define the tick frequency: when the pulsometer widget is updating the scre
 #### Watch Face Setup
 
 ```c
-void pulsometer_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void pulsometer_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
     (void) settings;
     if (*context_ptr == NULL) *context_ptr = malloc(sizeof(pulsometer_state_t));
 }
diff --git a/movement/make/Makefile b/movement/make/Makefile
index b7a0e6e2..4910b102 100755
--- a/movement/make/Makefile
+++ b/movement/make/Makefile
@@ -40,6 +40,7 @@ SRCS += \
   ../watch_faces/demos/voltage_face.c \
   ../watch_faces/demos/lis2dh_logging_face.c \
   ../watch_faces/demos/demo_face.c \
+  ../watch_faces/demos/hello_there_face.c \
   ../watch_faces/complications/beats_face.c \
   ../watch_faces/complications/day_one_face.c \
   ../watch_faces/complications/stopwatch_face.c \
diff --git a/movement/movement.c b/movement/movement.c
index cdd4ff06..3e22ace5 100644
--- a/movement/movement.c
+++ b/movement/movement.c
@@ -7,6 +7,7 @@
 
 movement_state_t movement_state;
 void * watch_face_contexts[MOVEMENT_NUM_FACES];
+watch_date_time scheduled_tasks[MOVEMENT_NUM_FACES];
 const int32_t movement_le_inactivity_deadlines[8] = {INT_MAX, 3600, 7200, 21600, 43200, 86400, 172800, 604800};
 const int16_t movement_timeout_inactivity_deadlines[4] = {60, 120, 300, 1800};
 movement_event_t event;
@@ -99,6 +100,29 @@ static void _movement_handle_background_tasks(void) {
     movement_state.needs_background_tasks_handled = false;
 }
 
+static void _movement_handle_scheduled_tasks(void) {
+    watch_date_time date_time = watch_rtc_get_date_time();
+    uint8_t num_active_tasks = 0;
+
+    for(uint8_t i = 0; i < MOVEMENT_NUM_FACES; i++) {
+        if (scheduled_tasks[i].reg) {
+            if (scheduled_tasks[i].reg == date_time.reg) {
+                scheduled_tasks[i].reg = 0;
+                movement_event_t background_event = { EVENT_BACKGROUND_TASK, 0 };
+                watch_faces[i].loop(background_event, &movement_state.settings, watch_face_contexts[i]);
+            } else {
+                num_active_tasks++;
+            }
+        }
+    }
+
+    if (num_active_tasks == 0) {
+        movement_state.has_scheduled_background_task = false;
+    } else {
+        _movement_reset_inactivity_countdown();
+    }
+}
+
 void movement_request_tick_frequency(uint8_t freq) {
     if (freq == 128) return; // Movement uses the 128 Hz tick internally
     RTC->MODE2.INTENCLR.reg = 0xFE; // disable all callbacks except the 128 Hz one
@@ -125,6 +149,14 @@ void movement_move_to_next_face(void) {
     movement_move_to_face((movement_state.current_watch_face + 1) % MOVEMENT_NUM_FACES);
 }
 
+void movement_schedule_background_task(watch_date_time date_time) {
+    watch_date_time now = watch_rtc_get_date_time();
+    if (date_time.reg > now.reg) {
+        movement_state.has_scheduled_background_task = true;
+        scheduled_tasks[movement_state.current_watch_face].reg = date_time.reg;
+    }
+}
+
 void movement_play_signal(void) {
     watch_buzzer_play_note(BUZZER_NOTE_C8, 75);
     watch_buzzer_play_note(BUZZER_NOTE_REST, 100);
@@ -161,6 +193,7 @@ void app_setup(void) {
     if (is_first_launch) {
         for(uint8_t i = 0; i < MOVEMENT_NUM_FACES; i++) {
             watch_face_contexts[i] = NULL;
+            scheduled_tasks[i].reg = 0;
             is_first_launch = false;
         }
 
@@ -185,7 +218,7 @@ void app_setup(void) {
         movement_request_tick_frequency(1);
 
         for(uint8_t i = 0; i < MOVEMENT_NUM_FACES; i++) {
-            watch_faces[i].setup(&movement_state.settings, &watch_face_contexts[i]);
+            watch_faces[i].setup(&movement_state.settings, i, &watch_face_contexts[i]);
         }
 
         watch_faces[movement_state.current_watch_face].activate(&movement_state.settings, watch_face_contexts[movement_state.current_watch_face]);
@@ -230,6 +263,9 @@ bool app_loop(void) {
     // handle background tasks, if the alarm handler told us we need to
     if (movement_state.needs_background_tasks_handled) _movement_handle_background_tasks();
 
+    // if we have a scheduled background task, handle that here:
+    if (event.event_type == EVENT_TICK && movement_state.has_scheduled_background_task) _movement_handle_scheduled_tasks();
+
     // if we have timed out of our low energy mode countdown, enter low energy mode.
     if (movement_state.le_mode_ticks == 0) {
         movement_state.le_mode_ticks = -1;
diff --git a/movement/movement.h b/movement/movement.h
index 62e4120b..edb1fabc 100644
--- a/movement/movement.h
+++ b/movement/movement.h
@@ -2,6 +2,7 @@
 #define MOVEMENT_H_
 #include <stdio.h>
 #include <stdbool.h>
+#include "watch.h"
 
 // Movement Preferences
 // These four 32-bit structs store information about the wearer and their preferences. Tentatively, the plan is
@@ -113,13 +114,16 @@ extern const char movement_valid_position_1_chars[];
   * @param settings A pointer to the global Movement settings. You can use this to inform how you present your
   *                 display to the user (i.e. taking into account whether they have silenced the buttons, or if
   *                 they prefer 12 or 24-hour mode). You can also change these settings if you like.
+  * @param watch_face_index The index of this watch face in the global array of watch faces; 0 is the first face,
+  *                         1 is the second, etc. You may stash this value in your context if you wish to reference
+  *                         it later; your watch face's index is set at launch and will not change.
   * @param context_ptr A pointer to a pointer; at first invocation, this value will be NULL, and you can set it
   *                    to any value you like. Subsequent invocations will pass in whatever value you previously
   *                    set. You may want to check if this is NULL and if so, allocate some space to store any
   *                    data required for your watch face.
   *
   */
-typedef void (*watch_face_setup)(movement_settings_t *settings, void ** context_ptr);
+typedef void (*watch_face_setup)(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 
 /** @brief Prepare to go on-screen.
   * @details This function is called just before your watch enters the foreground. If your watch face has any
@@ -228,6 +232,7 @@ typedef struct {
 
     // background task handling
     bool needs_background_tasks_handled;
+    bool has_scheduled_background_task;
 
     // low energy mode countdown
     int32_t le_mode_ticks;
@@ -244,8 +249,15 @@ typedef struct {
 void movement_move_to_face(uint8_t watch_face_index);
 void movement_move_to_next_face(void);
 void movement_illuminate_led(void);
+
+// note: requesting a tick frequency of 0 will break any scheduled background tasks.
+// this will be fixed in a future refactor of the tick mechanism.
 void movement_request_tick_frequency(uint8_t freq);
 
+// note: watch faces can only schedule a background task when in the foreground, since
+// movement will associate the scheduled task with the currently active face.
+void movement_schedule_background_task(watch_date_time date_time);
+
 void movement_play_signal(void);
 void movement_play_alarm(void);
 
diff --git a/movement/movement_config.h b/movement/movement_config.h
index 6aeb0b83..afb2902c 100644
--- a/movement/movement_config.h
+++ b/movement/movement_config.h
@@ -16,6 +16,7 @@
 #include "totp_face.h"
 #include "lis2dh_logging_face.h"
 #include "demo_face.h"
+#include "hello_there_face.h"
 
 const watch_face_t watch_faces[] = {
     simple_clock_face,
diff --git a/movement/watch_faces/clock/simple_clock_face.c b/movement/watch_faces/clock/simple_clock_face.c
index 72f7713f..b80a3026 100644
--- a/movement/watch_faces/clock/simple_clock_face.c
+++ b/movement/watch_faces/clock/simple_clock_face.c
@@ -3,23 +3,34 @@
 #include "watch.h"
 #include "watch_utility.h"
 
-void simple_clock_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void simple_clock_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
     (void) settings;
-    // the only context we need is the timestamp of the previous tick.
-    if (*context_ptr == NULL) *context_ptr = malloc(sizeof(uint32_t));
+    (void) watch_face_index;
+
+    if (*context_ptr == NULL) {
+        *context_ptr = malloc(sizeof(simple_clock_state_t));
+        simple_clock_state_t *state = (simple_clock_state_t *)*context_ptr;
+        state->signal_enabled = false;
+        state->watch_face_index = watch_face_index;
+    }
 }
 
 void simple_clock_face_activate(movement_settings_t *settings, void *context) {
+    simple_clock_state_t *state = (simple_clock_state_t *)context;
+
     if (watch_tick_animation_is_running()) watch_stop_tick_animation();
 
     if (settings->bit.clock_mode_24h) watch_set_indicator(WATCH_INDICATOR_24H);
+    if (state->signal_enabled) watch_set_indicator(WATCH_INDICATOR_SIGNAL);
 
     watch_set_colon();
+
     // this ensures that none of the timestamp fields will match, so we can re-render them all.
-    *((uint32_t *)context) = 0xFFFFFFFF;
+    state->previous_date_time = 0xFFFFFFFF;
 }
 
 bool simple_clock_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
+    simple_clock_state_t *state = (simple_clock_state_t *)context;
     char buf[11];
     uint8_t pos;
 
@@ -30,8 +41,8 @@ bool simple_clock_face_loop(movement_event_t event, movement_settings_t *setting
         case EVENT_TICK:
         case EVENT_LOW_ENERGY_UPDATE:
             date_time = watch_rtc_get_date_time();
-            previous_date_time = *((uint32_t *)context);
-            *((uint32_t *)context) = date_time.reg;
+            previous_date_time = state->previous_date_time;
+            state->previous_date_time = date_time.reg;
 
             if (date_time.reg >> 6 == previous_date_time >> 6 && event.event_type != EVENT_LOW_ENERGY_UPDATE) {
                 // everything before seconds is the same, don't waste cycles setting those segments.
@@ -69,7 +80,25 @@ bool simple_clock_face_loop(movement_event_t event, movement_settings_t *setting
         case EVENT_LIGHT_BUTTON_DOWN:
             movement_illuminate_led();
             break;
-        case EVENT_ALARM_BUTTON_UP:
+        case EVENT_ALARM_LONG_PRESS:
+            state->signal_enabled = !state->signal_enabled;
+            if (state->signal_enabled) watch_set_indicator(WATCH_INDICATOR_SIGNAL);
+            else watch_clear_indicator(WATCH_INDICATOR_SIGNAL);
+            break;
+        case EVENT_BACKGROUND_TASK:
+            // uncomment this line to snap back to the clock face when the hour signal sounds:
+            // movement_move_to_face(state->watch_face_index);
+            if (watch_is_buzzer_or_led_enabled()) {
+                // if we are in the foreground, we can just beep.
+                movement_play_signal();
+            } else {
+                // if we were in the background, we need to enable the buzzer peripheral first,
+                watch_enable_buzzer();
+                // beep quickly (this call blocks for 275 ms),
+                movement_play_signal();
+                // and then turn the buzzer peripheral off again.
+                watch_disable_buzzer();
+            }
             break;
         default:
             break;
@@ -82,3 +111,13 @@ void simple_clock_face_resign(movement_settings_t *settings, void *context) {
     (void) settings;
     (void) context;
 }
+
+bool simple_clock_face_wants_background_task(movement_settings_t *settings, void *context) {
+    (void) settings;
+    simple_clock_state_t *state = (simple_clock_state_t *)context;
+    if (!state->signal_enabled) return false;
+
+    watch_date_time date_time = watch_rtc_get_date_time();
+
+    return date_time.unit.minute == 59;
+}
diff --git a/movement/watch_faces/clock/simple_clock_face.h b/movement/watch_faces/clock/simple_clock_face.h
index 3db894d2..e2ad0ee8 100644
--- a/movement/watch_faces/clock/simple_clock_face.h
+++ b/movement/watch_faces/clock/simple_clock_face.h
@@ -3,19 +3,24 @@
 
 #include "movement.h"
 
-void simple_clock_face_setup(movement_settings_t *settings, void ** context_ptr);
+typedef struct {
+    uint32_t previous_date_time;
+    uint8_t watch_face_index;
+    bool signal_enabled;
+} simple_clock_state_t;
+
+void simple_clock_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void simple_clock_face_activate(movement_settings_t *settings, void *context);
 bool simple_clock_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void simple_clock_face_resign(movement_settings_t *settings, void *context);
-
-uint8_t simple_clock_face_get_weekday(uint16_t day, uint16_t month, uint16_t year);
+bool simple_clock_face_wants_background_task(movement_settings_t *settings, void *context);
 
 static const watch_face_t simple_clock_face = {
     simple_clock_face_setup,
     simple_clock_face_activate,
     simple_clock_face_loop,
     simple_clock_face_resign,
-    NULL
+    simple_clock_face_wants_background_task
 };
 
-#endif // SIMPLE_CLOCK_FACE_H_
\ No newline at end of file
+#endif // SIMPLE_CLOCK_FACE_H_
diff --git a/movement/watch_faces/clock/world_clock_face.c b/movement/watch_faces/clock/world_clock_face.c
index e1d96c97..5f2a1a86 100644
--- a/movement/watch_faces/clock/world_clock_face.c
+++ b/movement/watch_faces/clock/world_clock_face.c
@@ -4,8 +4,9 @@
 #include "watch.h"
 #include "watch_utility.h"
 
-void world_clock_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void world_clock_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(world_clock_state_t));
         world_clock_state_t *state = (world_clock_state_t *)*context_ptr;
diff --git a/movement/watch_faces/clock/world_clock_face.h b/movement/watch_faces/clock/world_clock_face.h
index 1c4525a4..b5e766bd 100644
--- a/movement/watch_faces/clock/world_clock_face.h
+++ b/movement/watch_faces/clock/world_clock_face.h
@@ -15,7 +15,7 @@ typedef struct {
     uint32_t previous_date_time;
 } world_clock_state_t;
 
-void world_clock_face_setup(movement_settings_t *settings, void ** context_ptr);
+void world_clock_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void world_clock_face_activate(movement_settings_t *settings, void *context);
 bool world_clock_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void world_clock_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/complications/beats_face.c b/movement/watch_faces/complications/beats_face.c
index 519d3e4e..b4c76db1 100644
--- a/movement/watch_faces/complications/beats_face.c
+++ b/movement/watch_faces/complications/beats_face.c
@@ -5,8 +5,9 @@
 
 const uint8_t BEAT_REFRESH_FREQUENCY = 8;
 
-void beats_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void beats_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
     (void) settings;
+    (void) watch_face_index;
     (void) context_ptr;
     if (*context_ptr == NULL) {
         *context_ptr = malloc(sizeof(beats_face_state_t));
diff --git a/movement/watch_faces/complications/beats_face.h b/movement/watch_faces/complications/beats_face.h
index bbe2396c..f11126d1 100644
--- a/movement/watch_faces/complications/beats_face.h
+++ b/movement/watch_faces/complications/beats_face.h
@@ -9,7 +9,7 @@ typedef struct {
 } beats_face_state_t;
 
 uint32_t clock2beats(uint32_t hours, uint32_t minutes, uint32_t seconds, uint32_t subseconds, int16_t utc_offset);
-void beats_face_setup(movement_settings_t *settings, void ** context_ptr);
+void beats_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void beats_face_activate(movement_settings_t *settings, void *context);
 bool beats_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void beats_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/complications/day_one_face.c b/movement/watch_faces/complications/day_one_face.c
index 3b185d04..6cc26106 100644
--- a/movement/watch_faces/complications/day_one_face.c
+++ b/movement/watch_faces/complications/day_one_face.c
@@ -17,8 +17,9 @@ static void _day_one_face_update(day_one_state_t state) {
     watch_display_string(buf, 0);
 }
 
-void day_one_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void day_one_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(day_one_state_t));
         memset(*context_ptr, 0, sizeof(day_one_state_t));
diff --git a/movement/watch_faces/complications/day_one_face.h b/movement/watch_faces/complications/day_one_face.h
index 06c7816e..3eb91195 100644
--- a/movement/watch_faces/complications/day_one_face.h
+++ b/movement/watch_faces/complications/day_one_face.h
@@ -15,7 +15,7 @@ typedef struct {
     bool birthday_changed;
 } day_one_state_t;
 
-void day_one_face_setup(movement_settings_t *settings, void ** context_ptr);
+void day_one_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void day_one_face_activate(movement_settings_t *settings, void *context);
 bool day_one_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void day_one_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/complications/pulsometer_face.c b/movement/watch_faces/complications/pulsometer_face.c
index d54d8ddf..f1da9633 100644
--- a/movement/watch_faces/complications/pulsometer_face.c
+++ b/movement/watch_faces/complications/pulsometer_face.c
@@ -6,8 +6,9 @@
 #define PULSOMETER_FACE_FREQUENCY_FACTOR (4ul) // refresh rate will be 2 to this power Hz (0 for 1 Hz, 2 for 4 Hz, etc.)
 #define PULSOMETER_FACE_FREQUENCY (1 << PULSOMETER_FACE_FREQUENCY_FACTOR)
 
-void pulsometer_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void pulsometer_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(pulsometer_state_t));
 }
 
diff --git a/movement/watch_faces/complications/pulsometer_face.h b/movement/watch_faces/complications/pulsometer_face.h
index cdb5b977..cb0b86bd 100644
--- a/movement/watch_faces/complications/pulsometer_face.h
+++ b/movement/watch_faces/complications/pulsometer_face.h
@@ -9,7 +9,7 @@ typedef struct {
     int16_t ticks;
 } pulsometer_state_t;
 
-void pulsometer_face_setup(movement_settings_t *settings, void ** context_ptr);
+void pulsometer_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void pulsometer_face_activate(movement_settings_t *settings, void *context);
 bool pulsometer_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void pulsometer_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/complications/stopwatch_face.c b/movement/watch_faces/complications/stopwatch_face.c
index d1d1ee73..4a145abf 100644
--- a/movement/watch_faces/complications/stopwatch_face.c
+++ b/movement/watch_faces/complications/stopwatch_face.c
@@ -3,8 +3,9 @@
 #include "stopwatch_face.h"
 #include "watch.h"
 
-void stopwatch_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void 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(stopwatch_state_t));
 }
 
diff --git a/movement/watch_faces/complications/stopwatch_face.h b/movement/watch_faces/complications/stopwatch_face.h
index 537c01ce..ff0c1796 100644
--- a/movement/watch_faces/complications/stopwatch_face.h
+++ b/movement/watch_faces/complications/stopwatch_face.h
@@ -10,7 +10,7 @@ typedef struct {
     uint8_t hours;
 } stopwatch_state_t;
 
-void stopwatch_face_setup(movement_settings_t *settings, void ** context_ptr);
+void stopwatch_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void stopwatch_face_activate(movement_settings_t *settings, void *context);
 bool stopwatch_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void stopwatch_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/complications/totp_face.c b/movement/watch_faces/complications/totp_face.c
index 4a34d7ad..468e6a8c 100644
--- a/movement/watch_faces/complications/totp_face.c
+++ b/movement/watch_faces/complications/totp_face.c
@@ -17,8 +17,9 @@ static uint8_t hmacKey[] = {0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x21, 0xde, 0xad, 0xbe
 
 static const uint32_t TIMESTEP = 30;
 
-void totp_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void totp_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(totp_state_t));
     TOTP(hmacKey, sizeof(hmacKey), TIMESTEP);
 }
diff --git a/movement/watch_faces/complications/totp_face.h b/movement/watch_faces/complications/totp_face.h
index 0527627a..1e2c5c02 100644
--- a/movement/watch_faces/complications/totp_face.h
+++ b/movement/watch_faces/complications/totp_face.h
@@ -10,7 +10,7 @@ typedef struct {
 
 } totp_state_t;
 
-void totp_face_setup(movement_settings_t *settings, void ** context_ptr);
+void totp_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void totp_face_activate(movement_settings_t *settings, void *context);
 bool totp_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void totp_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/demos/character_set_face.c b/movement/watch_faces/demos/character_set_face.c
index eabb133f..127c0fb3 100644
--- a/movement/watch_faces/demos/character_set_face.c
+++ b/movement/watch_faces/demos/character_set_face.c
@@ -3,8 +3,9 @@
 #include "character_set_face.h"
 #include "watch.h"
 
-void character_set_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void character_set_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(char));
 }
 
diff --git a/movement/watch_faces/demos/character_set_face.h b/movement/watch_faces/demos/character_set_face.h
index b27a8359..0c7cb85c 100644
--- a/movement/watch_faces/demos/character_set_face.h
+++ b/movement/watch_faces/demos/character_set_face.h
@@ -3,7 +3,7 @@
 
 #include "movement.h"
 
-void character_set_face_setup(movement_settings_t *settings, void ** context_ptr);
+void character_set_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void character_set_face_activate(movement_settings_t *settings, void *context);
 bool character_set_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void character_set_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/demos/demo_face.c b/movement/watch_faces/demos/demo_face.c
index 82256767..44a180ab 100644
--- a/movement/watch_faces/demos/demo_face.c
+++ b/movement/watch_faces/demos/demo_face.c
@@ -14,8 +14,9 @@ typedef enum {
     DEMO_FACE_NUM_FACES
 } demo_face_index_t;
 
-void demo_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void demo_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(demo_face_index_t));
         memset(*context_ptr, 0, sizeof(demo_face_index_t));
diff --git a/movement/watch_faces/demos/demo_face.h b/movement/watch_faces/demos/demo_face.h
index b9e36ffc..1bc39c4f 100644
--- a/movement/watch_faces/demos/demo_face.h
+++ b/movement/watch_faces/demos/demo_face.h
@@ -3,7 +3,7 @@
 
 #include "movement.h"
 
-void demo_face_setup(movement_settings_t *settings, void ** context_ptr);
+void demo_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void demo_face_activate(movement_settings_t *settings, void *context);
 bool demo_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void demo_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/demos/hello_there_face.c b/movement/watch_faces/demos/hello_there_face.c
new file mode 100644
index 00000000..fa7ea54e
--- /dev/null
+++ b/movement/watch_faces/demos/hello_there_face.c
@@ -0,0 +1,88 @@
+#include <stdlib.h>
+#include <string.h>
+#include "hello_there_face.h"
+#include "watch.h"
+
+void hello_there_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
+    // These next two lines just silence the compiler warnings associated with unused parameters.
+    // We have no use for the settings or the watch_face_index, so we make that explicit here.
+    (void) settings;
+    (void) watch_face_index;
+    // At boot, context_ptr will be NULL indicating that we don't have anyplace to store our context.
+    if (*context_ptr == NULL) {
+        // in this case, we allocate an area of memory sufficient to store the stuff we need to track.
+        *context_ptr = malloc(sizeof(hello_there_state_t));
+    }
+}
+
+void hello_there_face_activate(movement_settings_t *settings, void *context) {
+    // same as above: silence the warning, we don't need to check the settings.
+    (void) settings;
+    // we do however need to set some things in our context. Here we cast it to the correct type...
+    hello_there_state_t *state = (hello_there_state_t *)context;
+    // ...and set the initial state of our watch face. We start out displaying the word 'Hello',
+    state->current_word = 0;
+    // and animate by default.
+    state->animating = true;
+}
+
+bool hello_there_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
+    (void) settings;
+    hello_there_state_t *state = (hello_there_state_t *)context;
+
+    switch (event.event_type) {
+        case EVENT_ACTIVATE:
+        case EVENT_TICK:
+            // on activate and tick, if we are animating,
+            if (state->animating) {
+                // we display the current word,
+                if (state->current_word == 0) watch_display_string("Hello ", 4);
+                else watch_display_string(" there", 4);
+                // and increment it so that it will update on the next tick.
+                state->current_word = (state->current_word + 1) % 2;
+            }
+            break;
+        case EVENT_LIGHT_BUTTON_UP:
+            // when the user presses 'light', we illuminate the LED. We could override this if
+            // our UI needed an additional button for input, consuming the light button press
+            // but not illuminating the LED.
+            movement_illuminate_led();
+            break;
+        case EVENT_MODE_BUTTON_UP:
+            // when the user presses 'mode', we tell movement to move to the next watch face.
+            // movement will call our resign function, clear the screen, and transfer control
+            // to the next watch face in the list.
+            movement_move_to_next_face();
+            break;
+        case EVENT_ALARM_BUTTON_UP:
+            // when the user presses 'alarm', we toggle the state of the animation. If animating,
+            // we stop; if stopped, we resume.
+            state->animating = !state->animating;   
+            break;
+        case EVENT_LOW_ENERGY_UPDATE:
+            // This low energy mode update occurs once a minute, if the watch face is in the
+            // foreground when Movement enters low energy mode. We have the option of supporting
+            // this mode, but since our watch face animates once a second, the "Hello there" face
+            // isn't very useful in this mode. So we choose not to support it. (continued below)
+            break;
+        case EVENT_TIMEOUT:
+            // ... Instead, we respond to the timeout event. This event happens after a configurable
+            // interval on screen (1-30 minutes). The watch will give us this event as a chance to
+            // resign control if we want to, and in this case, we do.
+            // This function will return the watch to the first screen (usually a simple clock),
+            // and it will do it long before the watch enters low energy mode. This ensures we
+            // won't be on screen, and thus opts us out of getting the EVENT_LOW_ENERGY_UPDATE above.
+            movement_move_to_face(0);
+        default:
+            break;
+    }
+
+    return true;
+}
+
+void hello_there_face_resign(movement_settings_t *settings, void *context) {
+    // our watch face, like most watch faces, has nothing special to do when resigning.
+    // watch faces that enable a peripheral or interact with a sensor may want to turn it off here.
+    (void) settings;
+    (void) context;
+}
diff --git a/movement/watch_faces/demos/hello_there_face.h b/movement/watch_faces/demos/hello_there_face.h
new file mode 100644
index 00000000..0174b6f0
--- /dev/null
+++ b/movement/watch_faces/demos/hello_there_face.h
@@ -0,0 +1,24 @@
+#ifndef HELLO_THERE_FACE_H_
+#define HELLO_THERE_FACE_H_
+
+#include "movement.h"
+
+typedef struct {
+    uint8_t current_word;
+    bool animating;
+} hello_there_state_t;
+
+void hello_there_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
+void hello_there_face_activate(movement_settings_t *settings, void *context);
+bool hello_there_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
+void hello_there_face_resign(movement_settings_t *settings, void *context);
+
+static const watch_face_t hello_there_face = {
+    hello_there_face_setup,
+    hello_there_face_activate,
+    hello_there_face_loop,
+    hello_there_face_resign,
+    NULL
+};
+
+#endif // HELLO_THERE_FACE_H_
diff --git a/movement/watch_faces/demos/lis2dh_logging_face.c b/movement/watch_faces/demos/lis2dh_logging_face.c
index 9f5783fe..76892d07 100644
--- a/movement/watch_faces/demos/lis2dh_logging_face.c
+++ b/movement/watch_faces/demos/lis2dh_logging_face.c
@@ -86,8 +86,9 @@ static void _lis2dh_logging_face_log_data(lis2dh_logger_state_t *logger_state) {
     logger_state->z_interrupts_this_hour = 0;
 }
 
-void lis2dh_logging_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void lis2dh_logging_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(lis2dh_logger_state_t));
         memset(*context_ptr, 0, sizeof(lis2dh_logger_state_t));
diff --git a/movement/watch_faces/demos/lis2dh_logging_face.h b/movement/watch_faces/demos/lis2dh_logging_face.h
index b0faeca5..02b7ce9b 100644
--- a/movement/watch_faces/demos/lis2dh_logging_face.h
+++ b/movement/watch_faces/demos/lis2dh_logging_face.h
@@ -25,7 +25,7 @@ typedef struct {
     lis2dh_logger_data_point_t data[LIS2DH_LOGGING_NUM_DATA_POINTS];
 } lis2dh_logger_state_t;
 
-void lis2dh_logging_face_setup(movement_settings_t *settings, void ** context_ptr);
+void lis2dh_logging_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void lis2dh_logging_face_activate(movement_settings_t *settings, void *context);
 bool lis2dh_logging_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void lis2dh_logging_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/demos/voltage_face.c b/movement/watch_faces/demos/voltage_face.c
index fe43343f..a2b66854 100644
--- a/movement/watch_faces/demos/voltage_face.c
+++ b/movement/watch_faces/demos/voltage_face.c
@@ -11,8 +11,9 @@ static void _voltage_face_update_display(void) {
     watch_display_string(buf, 0);
 }
 
-void voltage_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void voltage_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
     (void) settings;
+    (void) watch_face_index;
     (void) context_ptr;
 }
 
diff --git a/movement/watch_faces/demos/voltage_face.h b/movement/watch_faces/demos/voltage_face.h
index da580da5..530cf34f 100644
--- a/movement/watch_faces/demos/voltage_face.h
+++ b/movement/watch_faces/demos/voltage_face.h
@@ -3,7 +3,7 @@
 
 #include "movement.h"
 
-void voltage_face_setup(movement_settings_t *settings, void ** context_ptr);
+void voltage_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void voltage_face_activate(movement_settings_t *settings, void *context);
 bool voltage_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void voltage_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/settings/preferences_face.c b/movement/watch_faces/settings/preferences_face.c
index ef65b1af..8cbe4c68 100644
--- a/movement/watch_faces/settings/preferences_face.c
+++ b/movement/watch_faces/settings/preferences_face.c
@@ -17,8 +17,9 @@ const char preferences_face_titles[PREFERENCES_FACE_NUM_PREFEFENCES][11] = {
     "LT   red  ",   // Light: red component
 };
 
-void preferences_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void preferences_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(uint8_t));
 }
 
diff --git a/movement/watch_faces/settings/preferences_face.h b/movement/watch_faces/settings/preferences_face.h
index af628ba3..54b4cff0 100644
--- a/movement/watch_faces/settings/preferences_face.h
+++ b/movement/watch_faces/settings/preferences_face.h
@@ -3,7 +3,7 @@
 
 #include "movement.h"
 
-void preferences_face_setup(movement_settings_t *settings, void ** context_ptr);
+void preferences_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void preferences_face_activate(movement_settings_t *settings, void *context);
 bool preferences_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void preferences_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/settings/set_time_face.c b/movement/watch_faces/settings/set_time_face.c
index 0f5af312..a32efe9f 100644
--- a/movement/watch_faces/settings/set_time_face.c
+++ b/movement/watch_faces/settings/set_time_face.c
@@ -5,8 +5,9 @@
 #define SET_TIME_FACE_NUM_SETTINGS (7)
 const char set_time_face_titles[SET_TIME_FACE_NUM_SETTINGS][3] = {"HR", "M1", "SE", "YR", "MO", "DA", "ZO"};
 
-void set_time_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void set_time_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(uint8_t));
 }
 
diff --git a/movement/watch_faces/settings/set_time_face.h b/movement/watch_faces/settings/set_time_face.h
index 21fb1e44..d58c4618 100644
--- a/movement/watch_faces/settings/set_time_face.h
+++ b/movement/watch_faces/settings/set_time_face.h
@@ -3,7 +3,7 @@
 
 #include "movement.h"
 
-void set_time_face_setup(movement_settings_t *settings, void ** context_ptr);
+void set_time_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void set_time_face_activate(movement_settings_t *settings, void *context);
 bool set_time_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void set_time_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/thermistor/thermistor_logging_face.c b/movement/watch_faces/thermistor/thermistor_logging_face.c
index 0d456785..094600c2 100644
--- a/movement/watch_faces/thermistor/thermistor_logging_face.c
+++ b/movement/watch_faces/thermistor/thermistor_logging_face.c
@@ -48,8 +48,9 @@ static void _thermistor_logging_face_update_display(thermistor_logger_state_t *l
     watch_display_string(buf, 0);
 }
 
-void thermistor_logging_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void thermistor_logging_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(thermistor_logger_state_t));
         memset(*context_ptr, 0, sizeof(thermistor_logger_state_t));
diff --git a/movement/watch_faces/thermistor/thermistor_logging_face.h b/movement/watch_faces/thermistor/thermistor_logging_face.h
index ece89396..03e7ff3c 100644
--- a/movement/watch_faces/thermistor/thermistor_logging_face.h
+++ b/movement/watch_faces/thermistor/thermistor_logging_face.h
@@ -18,7 +18,7 @@ typedef struct {
     thermistor_logger_data_point_t data[THERMISTOR_LOGGING_NUM_DATA_POINTS];
 } thermistor_logger_state_t;
 
-void thermistor_logging_face_setup(movement_settings_t *settings, void ** context_ptr);
+void thermistor_logging_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void thermistor_logging_face_activate(movement_settings_t *settings, void *context);
 bool thermistor_logging_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void thermistor_logging_face_resign(movement_settings_t *settings, void *context);
diff --git a/movement/watch_faces/thermistor/thermistor_readout_face.c b/movement/watch_faces/thermistor/thermistor_readout_face.c
index 5478f07d..f55a4210 100644
--- a/movement/watch_faces/thermistor/thermistor_readout_face.c
+++ b/movement/watch_faces/thermistor/thermistor_readout_face.c
@@ -17,8 +17,9 @@ static void _thermistor_readout_face_update_display(bool in_fahrenheit) {
     thermistor_driver_disable();
 }
 
-void thermistor_readout_face_setup(movement_settings_t *settings, void ** context_ptr) {
+void thermistor_readout_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
     (void) settings;
+    (void) watch_face_index;
     (void) context_ptr;
 }
 
diff --git a/movement/watch_faces/thermistor/thermistor_readout_face.h b/movement/watch_faces/thermistor/thermistor_readout_face.h
index 71d15427..dc4f1b99 100644
--- a/movement/watch_faces/thermistor/thermistor_readout_face.h
+++ b/movement/watch_faces/thermistor/thermistor_readout_face.h
@@ -3,7 +3,7 @@
 
 #include "movement.h"
 
-void thermistor_readout_face_setup(movement_settings_t *settings, void ** context_ptr);
+void thermistor_readout_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
 void thermistor_readout_face_activate(movement_settings_t *settings, void *context);
 bool thermistor_readout_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
 void thermistor_readout_face_resign(movement_settings_t *settings, void *context);
diff --git a/watch-library/watch/watch.c b/watch-library/watch/watch.c
index 844ed3d9..791fd974 100644
--- a/watch-library/watch/watch.c
+++ b/watch-library/watch/watch.c
@@ -38,3 +38,7 @@ void SYSTEM_Handler(void) {
 bool watch_is_battery_low(void) {
     return battery_is_low;
 }
+
+bool watch_is_buzzer_or_led_enabled(void){
+    return hri_mclk_get_APBCMASK_TCC0_bit(MCLK);
+}
diff --git a/watch-library/watch/watch.h b/watch-library/watch/watch.h
index 669a5ed1..064f90ec 100644
--- a/watch-library/watch/watch.h
+++ b/watch-library/watch/watch.h
@@ -73,4 +73,11 @@
   */
 bool watch_is_battery_low(void);
 
+/** @brief Returns true if either the buzzer or the LED driver is enabled.
+  * @details Both the buzzer and the LED use the TCC peripheral to drive their behavior. This function returns true if that
+  *          peripheral is enabled. You can use this function to determine whether you need to call the watch_disable_leds or
+  *          or watch_enable_buzzer functions before using these peripherals.
+  */
+bool watch_is_buzzer_or_led_enabled(void);
+
 #endif /* WATCH_H_ */
\ No newline at end of file