Fix euclidean hit mod

Add reset behavior for EXT clock input when MIDI clock source is selected.

Fixes: https://git.pinkduck.xyz/awonak/libGravity/issues/22

examples/clock_mod/clock_mod.ino

@@ -17,7 +17,7 @@
  *
  */
 
-#include "gravity.h"
+#include <libGravity.h>
 
 // Firmware state variables.
 struct Channel {

firmware/Gravity/Gravity.ino

@@ -2,7 +2,7 @@
  * @file Gravity.ino
  * @author Adam Wonak (https://github.com/awonak/)
  * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version v2.0.1 - June 2025 awonak - Full rewrite 
+ * @version v2.0.0 - June 2025 awonak - Full rewrite
  * @version v1.0 - August 2023 Oleksiy H - Initial release
  * @date 2025-07-04
  *
@@ -25,7 +25,7 @@
  * quantization of features like duty cycle (pulse width) or offset.
  * Additionally, this firmware replaces the sequencer with a Euclidean Rhythm
  * generator.
- * 
+ *
  * ENCODER:
  *      Press: change between selecting a parameter and editing the parameter.
  *      Hold & Rotate: change current selected output channel.
@@ -33,20 +33,22 @@
  * BTN1:
  *      Play/pause - start or stop the internal clock.
  *
- * BTN2: 
+ * BTN2:
  *      Shift - hold and rotate encoder to change current selected output channel.
  *
  * EXT:
- *      External clock input. When Gravity is set to INTERNAL clock mode, this
- *      input is used to reset clocks.
- * 
+ *      External clock input. When Gravity is set to INTERNAL or MIDI clock
+ *      source, this input is used to reset clocks.
+ *
  * CV1:
- * CV2:
  *      External analog input used to provide modulation to any channel parameter.
  * 
+ * CV2:
+ *      External analog input used to provide modulation to any channel parameter.
+ *
  */
 
-#include <gravity.h>
+#include <libGravity.h>
 
 #include "app_state.h"
 #include "channel.h"
@@ -64,6 +66,10 @@ void setup() {
     // Start Gravity.
     gravity.Init();
 
+    // Show bootsplash when initializing firmware.
+    Bootsplash();
+    delay(2000);
+
     // Initialize the state manager. This will load settings from EEPROM
     stateManager.initialize(app);
     InitGravity(app);
@@ -135,13 +141,12 @@ void HandleIntClockTick(uint32_t tick) {
                 break;
         }
 
-        const uint32_t pulse_high_ticks = CLOCK_MOD_PULSES[clock_index];
+        const uint16_t pulse_high_ticks = pgm_read_word_near(&CLOCK_MOD_PULSES[clock_index]);
         const uint32_t pulse_low_ticks = tick + max((pulse_high_ticks / 2), 1L);
 
         if (tick % pulse_high_ticks == 0) {
             gravity.pulse.High();
-        }
-        if (pulse_low_ticks % pulse_high_ticks == 0) {
+        } else if (pulse_low_ticks % pulse_high_ticks == 0) {
             gravity.pulse.Low();
         }
     }
@@ -152,13 +157,16 @@ void HandleIntClockTick(uint32_t tick) {
 }
 
 void HandleExtClockTick() {
-    if (gravity.clock.InternalSource()) {
-        // Use EXT as Reset when internally clocked.
-        ResetOutputs();
-        gravity.clock.Reset();
-    } else {
-        // Register clock tick.
-        gravity.clock.Tick();
+    switch (app.selected_source) {
+        case Clock::SOURCE_INTERNAL:
+        case Clock::SOURCE_EXTERNAL_MIDI:
+            // Use EXT as Reset when not used for clock source.
+            ResetOutputs();
+            gravity.clock.Reset();
+            break;
+        default:
+            // Register EXT cv clock tick.
+            gravity.clock.Tick();
     }
     app.refresh_screen = true;
 }
@@ -168,6 +176,21 @@ void HandleExtClockTick() {
 //
 
 void HandlePlayPressed() {
+    // Check if SHIFT is pressed to mute all/current channel.
+    if (gravity.shift_button.On()) {
+        if (app.selected_channel == 0) {
+            // Mute all channels
+            for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
+                app.channel[i].toggleMute();
+            }
+        } else {
+            // Mute selected channel
+            auto& ch = GetSelectedChannel();
+            ch.toggleMute();
+        }
+        return;
+    }
+
     gravity.clock.IsPaused()
         ? gravity.clock.Start()
         : gravity.clock.Stop();
@@ -181,17 +204,17 @@ void HandleEncoderPressed() {
         if (app.selected_channel == 0) {  // main page
             // TODO: rewrite as switch
             if (app.selected_param == PARAM_MAIN_ENCODER_DIR) {
-                bool reversed = app.selected_sub_param == 1;
-                gravity.encoder.SetReverseDirection(reversed);
+                app.encoder_reversed = app.selected_sub_param == 1;
+                gravity.encoder.SetReverseDirection(app.encoder_reversed);
             }
             if (app.selected_param == PARAM_MAIN_SAVE_DATA) {
-                if (app.selected_sub_param < MAX_SAVE_SLOTS) {
+                if (app.selected_sub_param < StateManager::MAX_SAVE_SLOTS) {
                     app.selected_save_slot = app.selected_sub_param;
                     stateManager.saveData(app);
                 }
             }
             if (app.selected_param == PARAM_MAIN_LOAD_DATA) {
-                if (app.selected_sub_param < MAX_SAVE_SLOTS) {
+                if (app.selected_sub_param < StateManager::MAX_SAVE_SLOTS) {
                     app.selected_save_slot = app.selected_sub_param;
                     stateManager.loadData(app, app.selected_save_slot);
                     InitGravity(app);
@@ -203,6 +226,14 @@ void HandleEncoderPressed() {
                     InitGravity(app);
                 }
             }
+            if (app.selected_param == PARAM_MAIN_FACTORY_RESET) {
+                if (app.selected_sub_param == 0) {  // Erase
+                    // Show bootsplash during slow erase operation.
+                    Bootsplash();
+                    stateManager.factoryReset(app);
+                    InitGravity(app);
+                }
+            }
         }
         // Only mark dirty and reset selected_sub_param when leaving editing mode.
         stateManager.markDirty();
@@ -272,11 +303,14 @@ void editMainParameter(int val) {
             break;
         case PARAM_MAIN_SAVE_DATA:
         case PARAM_MAIN_LOAD_DATA:
-            updateSelection(app.selected_sub_param, val, MAX_SAVE_SLOTS + 1);
+            updateSelection(app.selected_sub_param, val, StateManager::MAX_SAVE_SLOTS + 1);
             break;
         case PARAM_MAIN_RESET_STATE:
             updateSelection(app.selected_sub_param, val, 2);
             break;
+        case PARAM_MAIN_FACTORY_RESET:
+            updateSelection(app.selected_sub_param, val, 2);
+            break;
     }
 }
 

firmware/Gravity/app_state.h

@@ -12,16 +12,14 @@
 #ifndef APP_STATE_H
 #define APP_STATE_H
 
-#include <gravity.h>
+#include <libGravity.h>
 
 #include "channel.h"
 
 // Global state for settings and app behavior.
 struct AppState {
     int tempo = Clock::DEFAULT_TEMPO;
-    bool encoder_reversed = false;
-    bool refresh_screen = true;
-    bool editing_param = false;
+    Channel channel[Gravity::OUTPUT_COUNT];
     byte selected_param = 0;
     byte selected_sub_param = 0;  // Temporary value for editing params.
     byte selected_channel = 0;    // 0=tempo, 1-6=output channel
@@ -29,7 +27,9 @@ struct AppState {
     byte selected_save_slot = 0;  // The currently active save slot.
     Clock::Source selected_source = Clock::SOURCE_INTERNAL;
     Clock::Pulse selected_pulse = Clock::PULSE_PPQN_24;
-    Channel channel[Gravity::OUTPUT_COUNT];
+    bool editing_param = false;
+    bool encoder_reversed = false;
+    bool refresh_screen = true;
 };
 
 extern AppState app;
@@ -38,28 +38,4 @@ static Channel& GetSelectedChannel() {
     return app.channel[app.selected_channel - 1];
 }
 
-enum ParamsMainPage : uint8_t {
-    PARAM_MAIN_TEMPO,
-    PARAM_MAIN_SOURCE,
-    PARAM_MAIN_PULSE,
-    PARAM_MAIN_ENCODER_DIR,
-    PARAM_MAIN_SAVE_DATA,
-    PARAM_MAIN_LOAD_DATA,
-    PARAM_MAIN_RESET_STATE,
-    PARAM_MAIN_LAST,
-};
-
-enum ParamsChannelPage : uint8_t {
-    PARAM_CH_MOD,
-    PARAM_CH_PROB,
-    PARAM_CH_DUTY,
-    PARAM_CH_OFFSET,
-    PARAM_CH_SWING,
-    PARAM_CH_EUC_STEPS,
-    PARAM_CH_EUC_HITS,
-    PARAM_CH_CV1_DEST,
-    PARAM_CH_CV2_DEST,
-    PARAM_CH_LAST,
-};
-
 #endif  // APP_STATE_H

firmware/Gravity/channel.h

@@ -13,7 +13,7 @@
 #define CHANNEL_H
 
 #include <Arduino.h>
-#include <gravity.h>
+#include <libGravity.h>
 
 #include "euclidean.h"
 
@@ -34,28 +34,28 @@ static const byte MOD_CHOICE_SIZE = 25;
 
 // Negative numbers are multipliers, positive are divisors.
 static const int CLOCK_MOD[MOD_CHOICE_SIZE] PROGMEM = {
-    // Multipliers
-    -24, -16, -12, -8, -6, -4, -3, -2,
-    // Internal Clock Unity
-    1,
     // Divisors
-    2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 16, 24, 32, 64, 128};
+    128, 64, 32, 24, 16, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2,
+    // Internal Clock Unity (quarter note)
+    1,
+    // Multipliers
+    -2, -3, -4, -6, -8, -12, -16, -24};
 
 // This represents the number of clock pulses for a 96 PPQN clock source
 // that match the above div/mult mods.
 static const int CLOCK_MOD_PULSES[MOD_CHOICE_SIZE] PROGMEM = {
-    // Multiplier Pulses (96 / X)
-    4, 6, 8, 12, 16, 24, 32, 48,
+    // Divisor Pulses (96 * X)
+    12288, 6144, 3072, 2304, 1536, 1152, 1056, 960, 864, 768, 672, 576, 480, 384, 288, 192,
     // Internal Clock Pulses
     96,
-    // Divisor Pulses (96 * X)
-    192, 288, 384, 480, 576, 672, 768, 864, 960, 1056, 1152, 1536, 2304, 3072, 6144, 12288};
+    // Multiplier Pulses (96 / X)
+    48, 32, 24, 16, 12, 8, 6, 4};
 
-static const byte DEFAULT_CLOCK_MOD_INDEX = 8;  // x1 or 96 PPQN.
+static const byte DEFAULT_CLOCK_MOD_INDEX = 16;  // x1 or 96 PPQN.
 
-static const byte PULSE_PPQN_24_CLOCK_MOD_INDEX = 0;
-static const byte PULSE_PPQN_4_CLOCK_MOD_INDEX = 4;
-static const byte PULSE_PPQN_1_CLOCK_MOD_INDEX = 8;
+static const byte PULSE_PPQN_24_CLOCK_MOD_INDEX = MOD_CHOICE_SIZE - 1;
+static const byte PULSE_PPQN_4_CLOCK_MOD_INDEX = MOD_CHOICE_SIZE - 6;
+static const byte PULSE_PPQN_1_CLOCK_MOD_INDEX = MOD_CHOICE_SIZE - 9;
 
 class Channel {
    public:
@@ -161,6 +161,8 @@ class Channel {
     byte getSteps(bool withCvMod = false) const { return withCvMod ? pattern.GetSteps() : base_euc_steps; }
     byte getHits(bool withCvMod = false) const { return withCvMod ? pattern.GetHits() : base_euc_hits; }
 
+    void toggleMute() { mute = !mute; }
+
     /**
      * @brief Processes a clock tick and determines if the output should be high or low.
      * Note: this method is called from an ISR and must be kept as simple as possible.
@@ -168,6 +170,12 @@ class Channel {
      * @param output The output object to be modified.
      */
     void processClockTick(uint32_t tick, DigitalOutput& output) {
+        // Mute check
+        if (mute) {
+            output.Low();
+            return;
+        }
+
         const uint16_t mod_pulses = pgm_read_word_near(&CLOCK_MOD_PULSES[cvmod_clock_mod_index]);
 
         // Conditionally apply swing on down beats.
@@ -247,7 +255,7 @@ class Channel {
         int step_mod = _calculateMod(CV_DEST_EUC_STEPS, cv1_val, cv2_val, 0, MAX_PATTERN_LEN);
         pattern.SetSteps(base_euc_steps + step_mod);
 
-        int hit_mod = _calculateMod(CV_DEST_EUC_HITS, cv1_val, cv2_val, 0, MAX_PATTERN_LEN);
+        int hit_mod = _calculateMod(CV_DEST_EUC_HITS, cv1_val, cv2_val, 0, pattern.GetSteps());
         pattern.SetHits(base_euc_hits + hit_mod);
 
         // After all cvmod values are updated, recalculate clock pulse modifiers.
@@ -298,6 +306,9 @@ class Channel {
     // Euclidean pattern
     Pattern pattern;
 
+    // Mute channel flag
+    bool mute;
+
     // Pre-calculated pulse values for ISR performance
     uint16_t _duty_pulses;
     uint16_t _offset_pulses;

firmware/Gravity/display.h

@@ -96,6 +96,33 @@ constexpr uint8_t CHANNEL_BOXES_Y = 50;
 constexpr uint8_t CHANNEL_BOX_WIDTH = 18;
 constexpr uint8_t CHANNEL_BOX_HEIGHT = 14;
 
+// Menu items for editing global parameters.
+enum ParamsMainPage : uint8_t {
+    PARAM_MAIN_TEMPO,
+    PARAM_MAIN_SOURCE,
+    PARAM_MAIN_PULSE,
+    PARAM_MAIN_ENCODER_DIR,
+    PARAM_MAIN_SAVE_DATA,
+    PARAM_MAIN_LOAD_DATA,
+    PARAM_MAIN_RESET_STATE,
+    PARAM_MAIN_FACTORY_RESET,
+    PARAM_MAIN_LAST,
+};
+
+// Menu items for editing channel parameters.
+enum ParamsChannelPage : uint8_t {
+    PARAM_CH_MOD,
+    PARAM_CH_PROB,
+    PARAM_CH_DUTY,
+    PARAM_CH_OFFSET,
+    PARAM_CH_SWING,
+    PARAM_CH_EUC_STEPS,
+    PARAM_CH_EUC_HITS,
+    PARAM_CH_CV1_DEST,
+    PARAM_CH_CV2_DEST,
+    PARAM_CH_LAST,
+};
+
 // Helper function to draw centered text
 void drawCenteredText(const char* text, int y, const uint8_t* font) {
     gravity.display.setFont(font);
@@ -187,10 +214,10 @@ void swingDivisionMark() {
 
 // Human friendly display value for save slot.
 String displaySaveSlot(int slot) {
-    if (slot >= 0 && slot < MAX_SAVE_SLOTS / 2) {
+    if (slot >= 0 && slot < StateManager::MAX_SAVE_SLOTS / 2) {
         return String("A") + String(slot + 1);
-    } else if (slot >= MAX_SAVE_SLOTS / 2 && slot <= MAX_SAVE_SLOTS) {
-        return String("B") + String(slot - (MAX_SAVE_SLOTS / 2) + 1);
+    } else if (slot >= StateManager::MAX_SAVE_SLOTS / 2 && slot <= StateManager::MAX_SAVE_SLOTS) {
+        return String("B") + String(slot - (StateManager::MAX_SAVE_SLOTS / 2) + 1);
     }
 }
 
@@ -256,7 +283,7 @@ void DisplayMainPage() {
             break;
         case PARAM_MAIN_SAVE_DATA:
         case PARAM_MAIN_LOAD_DATA:
-            if (app.selected_sub_param == MAX_SAVE_SLOTS) {
+            if (app.selected_sub_param == StateManager::MAX_SAVE_SLOTS) {
                 mainText = F("x");
                 subText = F("BACK TO MAIN");
             } else {
@@ -278,13 +305,23 @@ void DisplayMainPage() {
                 mainText = F("x");
                 subText = F("BACK TO MAIN");
             }
+            break;
+        case PARAM_MAIN_FACTORY_RESET:
+            if (app.selected_sub_param == 0) {
+                mainText = F("DEL");
+                subText = F("FACTORY RESET");
+            } else {
+                mainText = F("x");
+                subText = F("BACK TO MAIN");
+            }
+            break;
     }
 
     drawCenteredText(mainText.c_str(), MAIN_TEXT_Y, LARGE_FONT);
     drawCenteredText(subText.c_str(), SUB_TEXT_Y, TEXT_FONT);
 
     // Draw Main Page menu items
-    String menu_items[PARAM_MAIN_LAST] = {F("TEMPO"), F("SOURCE"), F("PULSE OUT"), F("ENCODER DIR"), F("SAVE"), F("LOAD"), F("RESET")};
+    String menu_items[PARAM_MAIN_LAST] = {F("TEMPO"), F("SOURCE"), F("PULSE OUT"), F("ENCODER DIR"), F("SAVE"), F("LOAD"), F("RESET"), F("ERASE")};
     drawMenuItems(menu_items, PARAM_MAIN_LAST);
 }
 
@@ -428,7 +465,25 @@ void UpdateDisplay() {
             DisplayChannelPage();
         }
         // Global channel select UI.
-        DisplaySelectedChannel();
+            DisplaySelectedChannel();
+    } while (gravity.display.nextPage());
+}
+
+void Bootsplash() {
+    gravity.display.firstPage();
+    do {
+        int textWidth;
+        String loadingText = F("LOADING....");
+        gravity.display.setFont(TEXT_FONT);
+
+        textWidth = gravity.display.getStrWidth(StateManager::SKETCH_NAME);
+        gravity.display.drawStr(16 + (textWidth / 2), 20, StateManager::SKETCH_NAME);
+
+        textWidth = gravity.display.getStrWidth(StateManager::SEMANTIC_VERSION);
+        gravity.display.drawStr(16 + (textWidth / 2), 32, StateManager::SEMANTIC_VERSION);
+
+        textWidth = gravity.display.getStrWidth(loadingText.c_str());
+        gravity.display.drawStr(26 + (textWidth / 2), 44, loadingText.c_str());
     } while (gravity.display.nextPage());
 }
 

firmware/Gravity/save_state.cpp

@@ -15,65 +15,86 @@
 
 #include "app_state.h"
 
+// Define the constants for the current firmware.
+const char StateManager::SKETCH_NAME[] = "ALT GRAVITY";
+const char StateManager::SEMANTIC_VERSION[] = "V2.0.0BETA2";  // NOTE: This should match the version in the library.properties file.
+
+// Number of available save slots.
+const byte StateManager::MAX_SAVE_SLOTS = 10;
+const byte StateManager::TRANSIENT_SLOT = 10;
+
+// Define the minimum amount of time between EEPROM writes.
+const unsigned long StateManager::SAVE_DELAY_MS = 2000;
+
 // Calculate the starting address for EepromData, leaving space for metadata.
-static const int EEPROM_DATA_START_ADDR = sizeof(StateManager::Metadata);
+const int StateManager::METADATA_START_ADDR = 0;
+const int StateManager::EEPROM_DATA_START_ADDR = sizeof(StateManager::Metadata);
 
 StateManager::StateManager() : _isDirty(false), _lastChangeTime(0) {}
 
 bool StateManager::initialize(AppState& app) {
     if (_isDataValid()) {
-        // Load data from the transient slot.
-        return loadData(app, MAX_SAVE_SLOTS);
-    } else {
-        // EEPROM does not contain save data for this firmware & version.
-        // Initialize eeprom and save default patter to all save slots.
-        reset(app);
-        _saveMetadata();
-        // MAX_SAVE_SLOTS slot is reserved for transient state.
-        for (int i = 0; i <= MAX_SAVE_SLOTS; i++) {
-            app.selected_save_slot = i;
-            _saveState(app, i);
-        }
+        // Load global settings.
+        _loadMetadata(app);
+        // Load app data from the transient slot.
+        _loadState(app, TRANSIENT_SLOT);
+        return true;
+    }
+    // EEPROM does not contain save data for this firmware & version.
+    else {
+        // Erase EEPROM and initialize state. Save default pattern to all save slots.
+        factoryReset(app);
         return false;
     }
 }
 
 bool StateManager::loadData(AppState& app, byte slot_index) {
-    if (slot_index >= MAX_SAVE_SLOTS) return false;
+    // Check if slot_index is within max range + 1 for transient.
+    if (slot_index >= MAX_SAVE_SLOTS + 1) return false;
 
+    // Load the state data from the specified EEPROM slot and update the app state save slot.
     _loadState(app, slot_index);
+    app.selected_save_slot = slot_index;
+    // Persist this change in the global metadata.
+    _saveMetadata(app);
 
     return true;
 }
 
+// Save app state to user specified save slot.
 void StateManager::saveData(const AppState& app) {
-    if (app.selected_save_slot >= MAX_SAVE_SLOTS) return;
+    // Check if slot_index is within max range + 1 for transient.
+    if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1) return;
 
     _saveState(app, app.selected_save_slot);
+    _saveMetadata(app);
     _isDirty = false;
 }
 
+// Save transient state if it has changed and enough time has passed since last save.
 void StateManager::update(const AppState& app) {
     if (_isDirty && (millis() - _lastChangeTime > SAVE_DELAY_MS)) {
-        // MAX_SAVE_SLOTS slot is reserved for transient state.
-        _saveState(app, MAX_SAVE_SLOTS);
+        _saveState(app, TRANSIENT_SLOT);
+        _saveMetadata(app);
         _isDirty = false;
     }
 }
 
 void StateManager::reset(AppState& app) {
-    app.tempo = Clock::DEFAULT_TEMPO;
-    app.encoder_reversed = false;
-    app.selected_param = 0;
-    app.selected_channel = 0;
-    app.selected_source = Clock::SOURCE_INTERNAL;
-    app.selected_pulse = Clock::PULSE_PPQN_24;
-    app.selected_save_slot = 0;
+    AppState default_app;
+    app.tempo = default_app.tempo;
+    app.selected_param = default_app.selected_param;
+    app.selected_channel = default_app.selected_channel;
+    app.selected_source = default_app.selected_source;
+    app.selected_pulse = default_app.selected_pulse;
 
     for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
         app.channel[i].Init();
     }
 
+    // Load global settings from Metadata
+    _loadMetadata(app);
+
     _isDirty = false;
 }
 
@@ -82,28 +103,48 @@ void StateManager::markDirty() {
     _lastChangeTime = millis();
 }
 
+// Erases all data in the EEPROM by writing 0 to every address.
+void StateManager::factoryReset(AppState& app) {
+    noInterrupts();
+    for (unsigned int i = 0; i < EEPROM.length(); i++) {
+        EEPROM.write(i, 0);
+    }
+    // Initialize eeprom and save default patter to all save slots.
+    _saveMetadata(app);
+    reset(app);
+    for (int i = 0; i < MAX_SAVE_SLOTS; i++) {
+        app.selected_save_slot = i;
+        _saveState(app, i);
+    }
+    _saveState(app, TRANSIENT_SLOT);
+    interrupts();
+}
+
 bool StateManager::_isDataValid() {
-    Metadata load_meta;
-    EEPROM.get(0, load_meta);
-    bool name_match = (strcmp(load_meta.sketch_name, SKETCH_NAME) == 0);
-    bool version_match = (load_meta.version == SKETCH_VERSION);
+    Metadata metadata;
+    EEPROM.get(METADATA_START_ADDR, metadata);
+    bool name_match = (strcmp(metadata.sketch_name, SKETCH_NAME) == 0);
+    bool version_match = (strcmp(metadata.version, SEMANTIC_VERSION) == 0);
     return name_match && version_match;
 }
 
 void StateManager::_saveState(const AppState& app, byte slot_index) {
-    if (app.selected_save_slot >= MAX_SAVE_SLOTS) return;
+    // Check if slot_index is within max range + 1 for transient.
+    if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1) return;
 
     noInterrupts();
     static EepromData save_data;
 
     save_data.tempo = app.tempo;
-    save_data.encoder_reversed = app.encoder_reversed;
     save_data.selected_param = app.selected_param;
     save_data.selected_channel = app.selected_channel;
     save_data.selected_source = static_cast<byte>(app.selected_source);
     save_data.selected_pulse = static_cast<byte>(app.selected_pulse);
-    save_data.selected_save_slot = app.selected_save_slot;
 
+    // TODO: break this out into a separate function. Save State should be
+    // broken out into global / per-channel save methods. When saving via
+    // "update" only save state for the current channel since other channels
+    // will not have changed when saving user edits.
     for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
         const auto& ch = app.channel[i];
         auto& save_ch = save_data.channel_data[i];
@@ -124,6 +165,9 @@ void StateManager::_saveState(const AppState& app, byte slot_index) {
 }
 
 void StateManager::_loadState(AppState& app, byte slot_index) {
+    // Check if slot_index is within max range + 1 for transient.
+    if (slot_index >= MAX_SAVE_SLOTS + 1) return;
+
     noInterrupts();
     static EepromData load_data;
     int address = EEPROM_DATA_START_ADDR + (slot_index * sizeof(EepromData));
@@ -131,12 +175,10 @@ void StateManager::_loadState(AppState& app, byte slot_index) {
 
     // Restore app state from loaded data.
     app.tempo = load_data.tempo;
-    app.encoder_reversed = load_data.encoder_reversed;
     app.selected_param = load_data.selected_param;
     app.selected_channel = load_data.selected_channel;
     app.selected_source = static_cast<Clock::Source>(load_data.selected_source);
     app.selected_pulse = static_cast<Clock::Pulse>(load_data.selected_pulse);
-    app.selected_save_slot = slot_index;
 
     for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
         auto& ch = app.channel[i];
@@ -155,11 +197,25 @@ void StateManager::_loadState(AppState& app, byte slot_index) {
     interrupts();
 }
 
-void StateManager::_saveMetadata() {
+void StateManager::_saveMetadata(const AppState& app) {
     noInterrupts();
     Metadata current_meta;
     strcpy(current_meta.sketch_name, SKETCH_NAME);
-    current_meta.version = SKETCH_VERSION;
-    EEPROM.put(0, current_meta);
+    strcpy(current_meta.version, SEMANTIC_VERSION);
+
+    // Global user settings
+    current_meta.selected_save_slot = app.selected_save_slot;
+    current_meta.encoder_reversed = app.encoder_reversed;
+
+    EEPROM.put(METADATA_START_ADDR, current_meta);
     interrupts();
 }
+
+void StateManager::_loadMetadata(AppState& app) {
+    noInterrupts();
+    Metadata metadata;
+    EEPROM.get(METADATA_START_ADDR, metadata);
+    app.selected_save_slot = metadata.selected_save_slot;
+    app.encoder_reversed = metadata.encoder_reversed;
+    interrupts();
+}

firmware/Gravity/save_state.h

@@ -13,21 +13,11 @@
 #define SAVE_STATE_H
 
 #include <Arduino.h>
-#include <gravity.h>
+#include <libGravity.h>
 
 // Forward-declare AppState to avoid circular dependencies.
 struct AppState;
 
-// Define the constants for the current firmware.
-const char SKETCH_NAME[] = "Gravity";
-const byte SKETCH_VERSION = 7;
-
-// Number of available save slots.
-const byte MAX_SAVE_SLOTS = 10;
-
-// Define the minimum amount of time between EEPROM writes.
-static const unsigned long SAVE_DELAY_MS = 2000;
-
 /**
  * @brief Manages saving and loading of the application state to and from EEPROM.
  * The number of user slots is defined by MAX_SAVE_SLOTS, and one additional slot
@@ -38,6 +28,11 @@ static const unsigned long SAVE_DELAY_MS = 2000;
  */
 class StateManager {
    public:
+    static const char SKETCH_NAME[];
+    static const char SEMANTIC_VERSION[];
+    static const byte MAX_SAVE_SLOTS;
+    static const byte TRANSIENT_SLOT;
+
     StateManager();
 
     // Populate the AppState instance with values from EEPROM if they exist.
@@ -52,11 +47,16 @@ class StateManager {
     void update(const AppState& app);
     // Indicate that state has changed and we should save.
     void markDirty();
+    // Erase all data stored in the EEPROM.
+    void factoryReset(AppState& app);
 
     // This struct holds the data that identifies the firmware version.
     struct Metadata {
-        byte version;
         char sketch_name[16];
+        char version[16];
+        // Additional global/hardware settings
+        byte selected_save_slot;
+        bool encoder_reversed;
     };
     struct ChannelState {
         byte base_clock_mod_index;
@@ -72,21 +72,24 @@ class StateManager {
     // This struct holds all the parameters we want to save.
     struct EepromData {
         int tempo;
-        bool encoder_reversed;
         byte selected_param;
         byte selected_channel;
         byte selected_source;
         byte selected_pulse;
-        byte selected_save_slot;
         ChannelState channel_data[Gravity::OUTPUT_COUNT];
     };
 
    private:
     bool _isDataValid();
-    void _saveMetadata();
+    void _saveMetadata(const AppState& app);
+    void _loadMetadata(AppState& app);
     void _saveState(const AppState& app, byte slot_index);
     void _loadState(AppState& app, byte slot_index);
 
+    static const unsigned long SAVE_DELAY_MS;
+    static const int METADATA_START_ADDR;
+    static const int EEPROM_DATA_START_ADDR;
+
     bool _isDirty;
     unsigned long _lastChangeTime;
 };

library.properties

@@ -0,0 +1,10 @@
+name=libGravity
+version=2.0.0beta2
+author=Adam Wonak
+maintainer=awonak <github.com/awonak>
+sentence=Hardware abstraction library for Sitka Instruments Gravity eurorack module
+category=Other
+license=MIT
+url=https://github.com/awonak/libGravity
+architectures=avr
+depends=uClock,RotaryEncoder,U8g2

src/clock.h

@@ -15,7 +15,7 @@
 #include <NeoHWSerial.h>
 
 #include "peripherials.h"
-#include "uClock.h"
+#include "uClock/uClock.h"
 
 // MIDI clock, start, stop, and continue byte definitions - based on MIDI 1.0 Standards.
 #define MIDI_CLOCK 0xF8
@@ -50,9 +50,6 @@ class Clock {
     void Init() {
         NeoSerial.begin(31250);
 
-        // Static pin definition for pulse out.
-        pinMode(PULSE_OUT_PIN, OUTPUT);
-
         // Initialize the clock library
         uClock.init();
         uClock.setClockMode(uClock.INTERNAL_CLOCK);

src/libGravity.cpp

@@ -1,5 +1,5 @@
 /**
- * @file gravity.cpp
+ * @file libGravity.cpp
  * @author Adam Wonak (https://github.com/awonak)
  * @brief Library for building custom scripts for the Sitka Instruments Gravity module.
  * @version 0.1
@@ -9,7 +9,7 @@
  *
  */
 
-#include "gravity.h"
+#include "libGravity.h"
 
 // Initialize the static pointer for the EncoderDir class to null. We want to
 // have a static pointer to decouple the ISR from the global gravity object.

src/libGravity.h

@@ -1,5 +1,5 @@
 /**
- * @file gravity.h
+ * @file libGravity.h
  * @author Adam Wonak (https://github.com/awonak)
  * @brief Library for building custom scripts for the Sitka Instruments Gravity module.
  * @version 0.1

src/uClock/uClock.cpp

@@ -32,7 +32,7 @@
  * DEALINGS IN THE SOFTWARE.
  */
 #include "uClock.h"
-#include "uClock/platforms/avr.h"
+#include "platforms/avr.h"
 
 //
 // Platform specific timer setup/control

uClock/uClock.h

@@ -1,180 +0,0 @@
-/*!
- *  @file       uClock.h
- *  Project     BPM clock generator for Arduino
- *  @brief      A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(RPI2040, Teensy, Seedstudio XIAO M0 and ESP32)
- *  @version    2.2.1
- *  @author     Romulo Silva
- *  @date       10/06/2017
- *  @license    MIT - (c) 2024 - Romulo Silva - contact@midilab.co
- *
- * 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 __U_CLOCK_H__
-#define __U_CLOCK_H__
-
-#include <Arduino.h>
-#include <inttypes.h>
-
-namespace umodular { namespace clock {
-
-#define MIN_BPM	1
-#define MAX_BPM	400
-
-#define PHASE_FACTOR 16
-#define PLL_X 220
-
-#define SECS_PER_MIN  (60UL)
-#define SECS_PER_HOUR (3600UL)
-#define SECS_PER_DAY  (SECS_PER_HOUR * 24L)
-
-class uClockClass {
-
-    public:
-        enum ClockMode {
-            INTERNAL_CLOCK = 0,
-            EXTERNAL_CLOCK
-        };
-
-        enum ClockState {
-            PAUSED = 0,
-            STARTING,
-            STARTED
-        };
-
-        enum PPQNResolution {
-            PPQN_1 = 1,
-            PPQN_2 = 2,
-            PPQN_4 = 4,
-            PPQN_8 = 8,
-            PPQN_12 = 12,
-            PPQN_24 = 24,
-            PPQN_48 = 48,
-            PPQN_96 = 96,
-            PPQN_384 = 384,
-            PPQN_480 = 480,
-            PPQN_960 = 960
-        };
-
-        ClockState clock_state;
-
-        uClockClass();
-
-        void setOnOutputPPQN(void (*callback)(uint32_t tick)) {
-            onOutputPPQNCallback = callback;
-        }
-
-        void setOnSync24(void (*callback)(uint32_t tick)) {
-            onSync24Callback = callback;
-        }
-
-        void setOnClockStart(void (*callback)()) {
-            onClockStartCallback = callback;
-        }
-
-        void setOnClockStop(void (*callback)()) {
-            onClockStopCallback = callback;
-        }
-
-        void init();
-        void setOutputPPQN(PPQNResolution resolution);
-        void setInputPPQN(PPQNResolution resolution);
-
-        void handleTimerInt();
-        void handleExternalClock();
-        void resetCounters();
-
-        // external class control
-        void start();
-        void stop();
-        void pause();
-        void setTempo(float bpm);
-        float getTempo();
-
-        // for software timer implementation(fallback for no board support)
-        void run();
-
-        // external timming control
-        void setClockMode(ClockMode tempo_mode);
-        ClockMode getClockMode();
-        void clockMe();
-        // for smooth slave tempo calculate display you should raise the
-        // buffer_size of ext_interval_buffer in between 64 to 128. 254 max size.
-        // note: this doesn't impact on sync time, only display time getTempo()
-        // if you dont want to use it, it is default set it to 1 for memory save
-        void setExtIntervalBuffer(uint8_t buffer_size);
-
-        // elapsed time support
-        uint8_t getNumberOfSeconds(uint32_t time);
-        uint8_t getNumberOfMinutes(uint32_t time);
-        uint8_t getNumberOfHours(uint32_t time);
-        uint8_t getNumberOfDays(uint32_t time);
-        uint32_t getNowTimer();
-        uint32_t getPlayTime();
-
-        uint32_t bpmToMicroSeconds(float bpm);
-
-    private:
-        float inline freqToBpm(uint32_t freq);
-        float inline constrainBpm(float bpm);
-        void calculateReferencedata();
-
-        void (*onOutputPPQNCallback)(uint32_t tick);
-        void (*onSync24Callback)(uint32_t tick);
-        void (*onClockStartCallback)();
-        void (*onClockStopCallback)();
-
-        // clock input/output control
-        PPQNResolution output_ppqn = PPQN_96;
-        PPQNResolution input_ppqn = PPQN_24;
-        // output and internal counters, ticks and references
-        uint32_t tick;
-        uint32_t int_clock_tick;
-        uint8_t mod_clock_counter;
-        uint16_t mod_clock_ref;
-
-        uint8_t mod_sync24_counter;
-        uint16_t mod_sync24_ref;
-        uint32_t sync24_tick;
-
-        // external clock control
-        volatile uint32_t ext_clock_us;
-        volatile uint32_t ext_clock_tick;
-        volatile uint32_t ext_interval;
-        uint32_t last_interval;
-        uint32_t sync_interval;
-
-        float tempo;
-        uint32_t start_timer;
-        ClockMode clock_mode;
-
-        volatile uint32_t * ext_interval_buffer = nullptr;
-        uint8_t ext_interval_buffer_size;
-        uint16_t ext_interval_idx;
-};
-
-} } // end namespace umodular::clock
-
-extern umodular::clock::uClockClass uClock;
-
-extern "C" {
-    extern volatile uint32_t _millis;
-}
-
-#endif /* __U_CLOCK_H__ */