reduce flash mem usage by moving common text to a const.

Fixes https://github.com/awonak/alt-gravity/issues/12

Reviewed-on: https://git.pinkduck.xyz/awonak/libGravity/pulls/23

firmware/Euclidean/Euclidean.ino

@@ -1,417 +0,0 @@
-/**
- * @file Gravity.ino
- * @author Adam Wonak (https://github.com/awonak/)
- * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version v2.0.1beta1 - February 2026 awonak
- * @date 2026-02-21
- *
- * @copyright MIT - (c) 2026 - Adam Wonak - adam.wonak@gmail.com
- *
- * This version of Gravity firmware is a full rewrite that leverages the
- * libGravity hardware abstraction library. The goal of this project was to
- * create an open source friendly version of the firmware that makes it easy
- * for users/developers to modify and create their own original alt firmware
- * implementations.
- *
- * The libGravity library represents wrappers around the
- * hardware peripherials to make it easy to interact with and add behavior
- * to them. The library tries not to make any assumptions about what the
- * firmware can or should do.
- *
- * The Gravity firmware is a slightly different implementation of the original
- * firmware. There are a few notable changes; the internal clock operates at
- * 96 PPQN instead of the original 24 PPQN, which allows for more granular
- * 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.
- *
- * BTN1:
- *      Play/pause - start or stop the internal clock.
- *
- * BTN2:
- *      Shift - hold and rotate encoder to change current selected output
- * channel.
- *
- * EXT:
- *      External clock input. When Gravity is set to INTERNAL or MIDI clock
- *      source, this input is used to reset clocks.
- *
- * CV1:
- *      External analog input used to provide modulation to any channel
- * parameter.
- *
- * CV2:
- *      External analog input used to provide modulation to any channel
- * parameter.
- *
- */
-
-#include <libGravity.h>
-
-#include "app_state.h"
-#include "channel.h"
-#include "display.h"
-#include "save_state.h"
-
-AppState app;
-StateManager stateManager;
-
-//
-// Arduino setup and loop.
-//
-
-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);
-
-  // Clock handlers.
-  gravity.clock.AttachIntHandler(HandleIntClockTick);
-  gravity.clock.AttachExtHandler(HandleExtClockTick);
-
-  // Encoder rotate and press handlers.
-  gravity.encoder.AttachPressHandler(HandleEncoderPressed);
-  gravity.encoder.AttachRotateHandler(HandleRotate);
-  gravity.encoder.AttachPressRotateHandler(HandlePressedRotate);
-
-  // Button press handlers.
-  gravity.play_button.AttachPressHandler(HandlePlayPressed);
-}
-
-void loop() {
-  // Process change in state of inputs and outputs.
-  gravity.Process();
-
-  // Read CVs and call the update function for each channel.
-  int cv1 = gravity.cv1.Read();
-  int cv2 = gravity.cv2.Read();
-
-  for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    auto &ch = app.channel[i];
-    // Only apply CV to the channel when the current channel has cv
-    // mod configured.
-    if (ch.isCvModActive()) {
-      ch.applyCvMod(cv1, cv2);
-    }
-  }
-
-  // Clock Run
-  if (app.cv_run == 1 || app.cv_run == 2) {
-    auto &cv = app.cv_run == 1 ? gravity.cv1 : gravity.cv2;
-    int val = cv.Read();
-    if (val > AnalogInput::GATE_THRESHOLD && gravity.clock.IsPaused()) {
-      gravity.clock.Start();
-      app.refresh_screen = true;
-    } else if (val < AnalogInput::GATE_THRESHOLD && !gravity.clock.IsPaused()) {
-      gravity.clock.Stop();
-      ResetOutputs();
-      app.refresh_screen = true;
-    }
-  }
-
-  // Clock Reset
-  if ((app.cv_reset == 1 &&
-       gravity.cv1.IsRisingEdge(AnalogInput::GATE_THRESHOLD)) ||
-      (app.cv_reset == 2 &&
-       gravity.cv2.IsRisingEdge(AnalogInput::GATE_THRESHOLD))) {
-    gravity.clock.Reset();
-  }
-
-  // Check for dirty state eligible to be saved.
-  stateManager.update(app);
-
-  if (app.refresh_screen) {
-    UpdateDisplay();
-  }
-}
-
-//
-// Firmware handlers for clocks.
-//
-
-void HandleIntClockTick(uint32_t tick) {
-  bool refresh = false;
-  for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    app.channel[i].processClockTick(tick, gravity.outputs[i]);
-
-    if (app.channel[i].isCvModActive()) {
-      refresh = true;
-    }
-  }
-
-  // Pulse Out gate
-  if (app.selected_pulse != Clock::PULSE_NONE) {
-    int clock_index;
-    switch (app.selected_pulse) {
-    case Clock::PULSE_PPQN_24:
-      clock_index = PULSE_PPQN_24_CLOCK_MOD_INDEX;
-      break;
-    case Clock::PULSE_PPQN_4:
-      clock_index = PULSE_PPQN_4_CLOCK_MOD_INDEX;
-      break;
-    case Clock::PULSE_PPQN_1:
-      clock_index = PULSE_PPQN_1_CLOCK_MOD_INDEX;
-      break;
-    }
-
-    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();
-    } else if (pulse_low_ticks % pulse_high_ticks == 0) {
-      gravity.pulse.Low();
-    }
-  }
-
-  if (!app.editing_param) {
-    app.refresh_screen |= refresh;
-  }
-}
-
-void HandleExtClockTick() {
-  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;
-}
-
-//
-// UI handlers for encoder and buttons.
-//
-
-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();
-  ResetOutputs();
-  app.refresh_screen = true;
-}
-
-void HandleEncoderPressed() {
-  // Check if leaving editing mode should apply a selection.
-  if (app.editing_param) {
-    if (app.selected_channel == 0) { // main page
-      // TODO: rewrite as switch
-      if (app.selected_param == PARAM_MAIN_ENCODER_DIR) {
-        app.encoder_reversed = app.selected_sub_param == 1;
-        gravity.encoder.SetReverseDirection(app.encoder_reversed);
-      }
-      if (app.selected_param == PARAM_MAIN_ROTATE_DISP) {
-        app.rotate_display = app.selected_sub_param == 1;
-        gravity.display.setFlipMode(app.rotate_display ? 1 : 0);
-      }
-      if (app.selected_param == PARAM_MAIN_SAVE_DATA) {
-        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 < StateManager::MAX_SAVE_SLOTS) {
-          app.selected_save_slot = app.selected_sub_param;
-          // Load pattern data into app state.
-          stateManager.loadData(app, app.selected_save_slot);
-          // Load global performance settings if they have changed.
-          if (gravity.clock.Tempo() != app.tempo) {
-            gravity.clock.SetTempo(app.tempo);
-          }
-          // Load global settings only if clock is not active.
-          if (gravity.clock.IsPaused()) {
-            InitGravity(app);
-          }
-        }
-      }
-      if (app.selected_param == PARAM_MAIN_RESET_STATE) {
-        if (app.selected_sub_param == 0) { // Reset
-          stateManager.reset(app);
-          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();
-    app.selected_sub_param = 0;
-  }
-
-  app.editing_param = !app.editing_param;
-  app.refresh_screen = true;
-}
-
-void HandleRotate(int val) {
-  // Shift & Rotate check
-  if (gravity.shift_button.On()) {
-    HandlePressedRotate(val);
-    return;
-  }
-
-  if (!app.editing_param) {
-    // Navigation Mode
-    const int max_param =
-        (app.selected_channel == 0) ? PARAM_MAIN_LAST : PARAM_CH_LAST;
-    updateSelection(app.selected_param, val, max_param);
-  } else {
-    // Editing Mode
-    if (app.selected_channel == 0) {
-      editMainParameter(val);
-    } else {
-      editChannelParameter(val);
-    }
-  }
-  app.refresh_screen = true;
-}
-
-void HandlePressedRotate(int val) {
-  updateSelection(app.selected_channel, val, Gravity::OUTPUT_COUNT + 1);
-  app.selected_param = 0;
-  stateManager.markDirty();
-  app.refresh_screen = true;
-}
-
-void editMainParameter(int val) {
-  switch (static_cast<ParamsMainPage>(app.selected_param)) {
-  case PARAM_MAIN_TEMPO:
-    if (gravity.clock.ExternalSource()) {
-      break;
-    }
-    gravity.clock.SetTempo(gravity.clock.Tempo() + val);
-    app.tempo = gravity.clock.Tempo();
-    break;
-  case PARAM_MAIN_RUN:
-    updateSelection(app.selected_sub_param, val, 3);
-    app.cv_run = app.selected_sub_param;
-    break;
-  case PARAM_MAIN_RESET:
-    updateSelection(app.selected_sub_param, val, 3);
-    app.cv_reset = app.selected_sub_param;
-    break;
-  case PARAM_MAIN_SOURCE: {
-    byte source = static_cast<int>(app.selected_source);
-    updateSelection(source, val, Clock::SOURCE_LAST);
-    app.selected_source = static_cast<Clock::Source>(source);
-    gravity.clock.SetSource(app.selected_source);
-    break;
-  }
-  case PARAM_MAIN_PULSE: {
-    byte pulse = static_cast<int>(app.selected_pulse);
-    updateSelection(pulse, val, Clock::PULSE_LAST);
-    app.selected_pulse = static_cast<Clock::Pulse>(pulse);
-    if (app.selected_pulse == Clock::PULSE_NONE) {
-      gravity.pulse.Low();
-    }
-    break;
-  }
-  // These changes are applied upon encoder button press.
-  case PARAM_MAIN_ENCODER_DIR:
-    updateSelection(app.selected_sub_param, val, 2);
-    break;
-  case PARAM_MAIN_ROTATE_DISP:
-    updateSelection(app.selected_sub_param, val, 2);
-    break;
-  case PARAM_MAIN_SAVE_DATA:
-  case PARAM_MAIN_LOAD_DATA:
-    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;
-  }
-}
-
-void editChannelParameter(int val) {
-  auto &ch = GetSelectedChannel();
-  switch (app.selected_param) {
-  case PARAM_CH_MOD:
-    ch.setClockMod(ch.getClockModIndex() + val);
-    break;
-  case PARAM_CH_EUC_STEPS:
-    ch.setSteps(ch.getSteps() + val);
-    break;
-  case PARAM_CH_EUC_HITS:
-    ch.setHits(ch.getHits() + val);
-    break;
-  case PARAM_CH_CV1_DEST: {
-    byte dest = static_cast<int>(ch.getCv1Dest());
-    updateSelection(dest, val, CV_DEST_LAST);
-    ch.setCv1Dest(static_cast<CvDestination>(dest));
-    break;
-  }
-  case PARAM_CH_CV2_DEST: {
-    byte dest = static_cast<int>(ch.getCv2Dest());
-    updateSelection(dest, val, CV_DEST_LAST);
-    ch.setCv2Dest(static_cast<CvDestination>(dest));
-    break;
-  }
-  }
-}
-
-// Changes the param by the value provided.
-void updateSelection(byte &param, int change, int maxValue) {
-  // Do not apply acceleration if max value is less than 25.
-  if (maxValue < 25) {
-    change = change > 0 ? 1 : -1;
-  }
-  param = constrain(param + change, 0, maxValue - 1);
-}
-
-//
-// App Helper functions.
-//
-
-void InitGravity(AppState &app) {
-  gravity.clock.SetTempo(app.tempo);
-  gravity.clock.SetSource(app.selected_source);
-  gravity.encoder.SetReverseDirection(app.encoder_reversed);
-  gravity.display.setFlipMode(app.rotate_display ? 1 : 0);
-}
-
-void ResetOutputs() {
-  for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    gravity.outputs[i].Low();
-  }
-}

firmware/Euclidean/app_state.h

@@ -1,44 +0,0 @@
-/**
- * @file app_state.h
- * @author Adam Wonak (https://github.com/awonak/)
- * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version 2.0.1
- * @date 2025-07-04
- *
- * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
- *
- */
-
-#ifndef APP_STATE_H
-#define APP_STATE_H
-
-#include <libGravity.h>
-
-#include "channel.h"
-
-// Global state for settings and app behavior.
-struct AppState {
-  int tempo = Clock::DEFAULT_TEMPO;
-  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
-  byte selected_swing = 0;
-  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;
-  byte cv_run = 0;
-  byte cv_reset = 0;
-  bool editing_param = false;
-  bool encoder_reversed = false;
-  bool rotate_display = false;
-  bool refresh_screen = true;
-};
-
-extern AppState app;
-
-static Channel &GetSelectedChannel() {
-  return app.channel[app.selected_channel - 1];
-}
-
-#endif // APP_STATE_H

firmware/Euclidean/channel.h

@@ -1,247 +0,0 @@
-/**
- * @file channel.h
- * @author Adam Wonak (https://github.com/awonak/)
- * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version 2.0.1
- * @date 2025-07-04
- *
- * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
- *
- */
-
-#ifndef CHANNEL_H
-#define CHANNEL_H
-
-#include <Arduino.h>
-#include <libGravity.h>
-
-#include "euclidean.h"
-
-// Enums for CV Mod destination
-enum CvDestination : uint8_t {
-  CV_DEST_NONE,
-  CV_DEST_MOD,
-  CV_DEST_EUC_STEPS,
-  CV_DEST_EUC_HITS,
-  CV_DEST_LAST,
-};
-
-static const byte MOD_CHOICE_SIZE = 25;
-
-// Negative numbers are multipliers, positive are divisors.
-static const int CLOCK_MOD[MOD_CHOICE_SIZE] PROGMEM = {
-    // Divisors
-    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 = {
-    // Divisor Pulses (96 * X)
-    12288, 6144, 3072, 2304, 1536, 1152, 1056, 960, 864, 768, 672, 576, 480,
-    384, 288, 192,
-    // Internal Clock Pulses
-    96,
-    // Multiplier Pulses (96 / X)
-    48, 32, 24, 16, 12, 8, 6, 4};
-
-static const byte DEFAULT_CLOCK_MOD_INDEX = 16; // x1 or 96 PPQN.
-
-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:
-  Channel() { Init(); }
-
-  void Init() {
-    // Reset base values to their defaults
-    base_clock_mod_index = DEFAULT_CLOCK_MOD_INDEX;
-    base_euc_steps = 1;
-    base_euc_hits = 1;
-
-    cvmod_clock_mod_index = base_clock_mod_index;
-
-    cv1_dest = CV_DEST_NONE;
-    cv2_dest = CV_DEST_NONE;
-
-    pattern.Init(DEFAULT_PATTERN);
-
-    // Calcule the clock mod pulses on init.
-    _recalculatePulses();
-  }
-
-  // Setters (Set the BASE value)
-
-  void setClockMod(int index) {
-    base_clock_mod_index = constrain(index, 0, MOD_CHOICE_SIZE - 1);
-    if (!isCvModActive()) {
-      cvmod_clock_mod_index = base_clock_mod_index;
-      _recalculatePulses();
-    }
-  }
-
-  // Euclidean
-  void setSteps(int val) {
-    base_euc_steps = constrain(val, 1, MAX_PATTERN_LEN);
-    if (cv1_dest != CV_DEST_EUC_STEPS && cv2_dest != CV_DEST_EUC_STEPS) {
-      pattern.SetSteps(val);
-    }
-  }
-  void setHits(int val) {
-    base_euc_hits = constrain(val, 1, base_euc_steps);
-    if (cv1_dest != CV_DEST_EUC_HITS && cv2_dest != CV_DEST_EUC_HITS) {
-      pattern.SetHits(val);
-    }
-  }
-
-  void setCv1Dest(CvDestination dest) { cv1_dest = dest; }
-  void setCv2Dest(CvDestination dest) { cv2_dest = dest; }
-  CvDestination getCv1Dest() const { return cv1_dest; }
-  CvDestination getCv2Dest() const { return cv2_dest; }
-
-  // Getters (Get the BASE value for editing or cv modded value for display)
-
-  int getClockMod(bool withCvMod = false) const {
-    return pgm_read_word_near(&CLOCK_MOD[getClockModIndex(withCvMod)]);
-  }
-  int getClockModIndex(bool withCvMod = false) const {
-    return withCvMod ? cvmod_clock_mod_index : base_clock_mod_index;
-  }
-  bool isCvModActive() const {
-    return cv1_dest != CV_DEST_NONE || cv2_dest != CV_DEST_NONE;
-  }
-
-  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.
-   * @param tick The current clock tick count.
-   * @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]);
-
-    // Euclidian rhythm cycle check
-    if (!output.On()) {
-      // Step check
-      if (tick % mod_pulses == 0) {
-        bool hit = true;
-        // Euclidean rhythm hit check
-        switch (pattern.NextStep()) {
-        case Pattern::REST:
-          hit = false;
-          break;
-        case Pattern::HIT:
-          hit &= true;
-          break;
-        }
-        if (hit) {
-          output.High();
-        }
-      }
-    }
-
-    // Output low check. Half pulse width.
-    const uint32_t duty_cycle_end_tick = tick + _duty_pulses;
-    if (duty_cycle_end_tick % mod_pulses == 0) {
-      output.Low();
-    }
-  }
-  /**
-   * @brief Calculate and store cv modded values using bipolar mapping.
-   * Default to base value if not the current CV destination.
-   *
-   * @param cv1_val analog input reading for cv1
-   * @param cv2_val analog input reading for cv2
-   *
-   */
-  void applyCvMod(int cv1_val, int cv2_val) {
-    // Note: This is optimized for cpu performance. This method is called
-    // from the main loop and stores the cv mod values. This reduces CPU
-    // cycles inside the internal clock interrupt, which is preferrable.
-    // However, if RAM usage grows too much, we have an opportunity to
-    // refactor this to store just the CV read values, and calculate the
-    // cv mod value per channel inside the getter methods by passing cv
-    // values. This would reduce RAM usage, but would introduce a
-    // significant CPU cost, which may have undesirable performance issues.
-    if (!isCvModActive()) {
-      cvmod_clock_mod_index = base_clock_mod_index;
-      return;
-    }
-
-    int dest_mod = _calculateMod(CV_DEST_MOD, cv1_val, cv2_val,
-                                 -(MOD_CHOICE_SIZE / 2), MOD_CHOICE_SIZE / 2);
-    cvmod_clock_mod_index = constrain(base_clock_mod_index + dest_mod, 0, 100);
-
-    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,
-                                pattern.GetSteps());
-    pattern.SetHits(base_euc_hits + hit_mod);
-
-    // After all cvmod values are updated, recalculate clock pulse modifiers.
-    _recalculatePulses();
-  }
-
-private:
-  int _calculateMod(CvDestination dest, int cv1_val, int cv2_val, int min_range,
-                    int max_range) {
-    int mod1 =
-        (cv1_dest == dest) ? map(cv1_val, -512, 512, min_range, max_range) : 0;
-    int mod2 =
-        (cv2_dest == dest) ? map(cv2_val, -512, 512, min_range, max_range) : 0;
-    return mod1 + mod2;
-  }
-
-  void _recalculatePulses() {
-    const uint16_t mod_pulses =
-        pgm_read_word_near(&CLOCK_MOD_PULSES[cvmod_clock_mod_index]);
-    _duty_pulses = max((long)(mod_pulses / 2L), 1L);
-  }
-
-  // User-settable base values.
-  byte base_clock_mod_index;
-  byte base_euc_steps;
-  byte base_euc_hits;
-
-  // Base value with cv mod applied.
-  byte cvmod_clock_mod_index;
-
-  // CV mod configuration
-  CvDestination cv1_dest;
-  CvDestination cv2_dest;
-
-  // Euclidean pattern
-  Pattern pattern;
-
-  // Mute channel flag
-  bool mute;
-
-  // Pre-calculated pulse values for ISR performance
-  uint16_t _duty_pulses;
-};
-
-#endif // CHANNEL_H

firmware/Euclidean/display.h

@@ -1,520 +0,0 @@
-/**
- * @file display.h
- * @author Adam Wonak (https://github.com/awonak/)
- * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version 2.0.1
- * @date 2025-07-04
- *
- * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
- *
- */
-
-#ifndef DISPLAY_H
-#define DISPLAY_H
-
-#include <Arduino.h>
-
-#include "app_state.h"
-#include "save_state.h"
-
-//
-// UI Display functions for drawing the UI to the OLED display.
-//
-
-/*
- * Font: velvetscreen.bdf 9pt
- * https://stncrn.github.io/u8g2-unifont-helper/
- * "%/0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
- */
-const uint8_t TEXT_FONT[437] U8G2_FONT_SECTION("velvetscreen") PROGMEM =
-    "\64\0\2\2\3\3\2\3\4\5\5\0\0\5\0\5\0\0\221\0\0\1\230 \4\200\134%\11\255tT"
-    "R\271RI(\6\252\334T\31)\7\252\134bJ\12+\7\233\345\322J\0,\5\221T\4-\5\213"
-    "f\6.\5\211T\2/"
-    "\6\244\354c\33\60\10\254\354T\64\223\2\61\7\353\354\222\254\6\62\11\254l"
-    "\66J*"
-    "\217\0\63\11\254l\66J\32\215\4\64\10\254l\242\34\272\0\65\11\254l\206\336h"
-    "$\0\66"
-    "\11\254\354T^\61)\0\67\10\254lF\216u\4\70\11\254\354TL*&"
-    "\5\71\11\254\354TL;"
-    ")\0:\6\231UR\0A\10\254\354T\34S\6B\11\254lV\34)\216\4C\11\254\354T\324\61"
-    ")\0D\10\254lV\64G\2E\10\254l\206\36z\4F\10\254l\206^\71\3G\11\254\354TN"
-    "\63)"
-    "\0H\10\254l\242\34S\6I\6\251T\206\0J\10\254\354k\231\24\0K\11\254l\242J\62"
-    "\225\1L\7\254lr{\4M\11\255t\362ZI\353\0N\11\255t\362TI\356\0O\10\254\354T"
-    "\64\223\2P\11\254lV\34)"
-    "g\0Q\10\254\354T\264b\12R\10\254lV\34\251\31S\11\254\354"
-    "FF\32\215\4T\7\253dVl\1U\10\254l\242\63)\0V\11\255t\262Ne\312\21W\12\255"
-    "t\262J*\251.\0X\11\254l\242L*\312\0Y\12\255tr\252\63\312(\2Z\7\253df*"
-    "\7p\10\255\364V\266\323\2q\7\255\364\216\257\5r\10\253d\242\32*"
-    "\2t\6\255t\376#w\11"
-    "\255\364V\245FN\13x\6\233dR\7\0\0\0\4\377\377\0";
-
-/*
- * Font: STK-L.bdf 36pt
- * https://stncrn.github.io/u8g2-unifont-helper/
- * "%/0123456789ABCDEFILNORSTUVXx"
- */
-const uint8_t LARGE_FONT[766] U8G2_FONT_SECTION("stk-l") =
-    "\35\0\4\4\4\5\3\1\6\20\30\0\0\27\0\0\0\1\77\0\0\2\341%'\17;\226\261\245FL"
-    "\64B\214\30\22\223\220)"
-    "Bj\10Q\232\214\42R\206\310\210\21d\304\30\32a\254\304\270!\0/\14"
-    "\272\272\275\311H\321g\343\306\1\60\37|\373\35CJT\20:"
-    "fW\207\320\210\60\42\304\204\30D\247"
-    "\214\331\354\20\11%"
-    "\212\314\0\61\24z\275\245a\244\12\231\71\63b\214\220q\363\377(E\6\62\33|"
-    "\373\35ShT\20:fl\344\14\211\231\301\306T\71\202#g\371\340\201\1\63\34|"
-    "\373\35ShT"
-    "\20:fl\344@r\264\263\222\344,\215\35\42\241\6\225\31\0\64 "
-    "|\373-!\203\206\214!\62\204"
-    "\314\220A#\10\215\30\65b\324\210Q\306\354\354\1\213\225\363\1\65\32|"
-    "\373\15\25[\214\234/\10)"
-    "Y\61j\350\310Y\32;DB\15*\63\0\66\33}\33\236SiV\14;gt^\230Y\302\202\324"
-    "\71\273;EbM\252\63\0\67\23|\373\205\25\17R\316\207\344\350p\312\201#"
-    "\347\35\0\70 |\373"
-    "\35ShT\20:f\331!\22D\310 "
-    ":\205\206\10\11B\307\354\354\20\11\65\250\314\0\71\32|\373"
-    "\35ShT\20:fg\207H,Q\223r\276\30DB\15*\63\0A\26}\33\246r\247\322P\62"
-    "j\310\250\21\343\354\335\203\357\354w\3B$}"
-    "\33\206Dj\226\214\42\61l\304\260\21\303F\14\33\61"
-    "\212\304\222MF\221\30v\316\236=\10\301b\11\0C\27}"
-    "\33\236Si\226\20Bft\376O\211\215"
-    " Db\215\42$\0D\33}\33\206Dj\226\214\32\62l\304\260\21\343\354\177vl\304("
-    "\22K\324"
-    "$\2E\22|\373\205\17R\316KD\30\215\234_>x`\0F\20|"
-    "\373\205\17R\316\227i\262\31"
-    "\71\377\22\0I\7s\333\204\77HL\15{\333\205\201\363\377\77|\360`\0N$}"
-    "\33\6\201\346\314"
-    "\35;\206\12U\242D&\306\230\30cd\210\221!fF\230\31a(+\314\256\63\67\0O\26}"
-    "\33"
-    "\236Si\226\214\32\61\316\376\277\33\61j\310\232Tg\0R\61\216;\6Ek\230\14#"
-    "\61n\304\270"
-    "\21\343F\214\33\61n\304\60\22\243\210\60Q\224j\310\260\61\243\306\20\232"
-    "\325\230QD\206\221\30\67b"
-    "\334\301\1S\42\216;\236c\211\226\220\42\61n\304\270\21c\307R\232,["
-    "\262\203\307\216\65h\16\25"
-    "\21&\253\320\0T\15}\33\206\17R\15\235\377\377\25\0U\21|"
-    "\373\205a\366\377\237\215\30\64D\15"
-    "*\63\0V\26\177\371\205\221\366\377\313\21\343\206\220\42C\25\11r'"
-    "\313\16\3X)~;\206\201\6"
-    "\217\221\30\66\204\20\31\42\244\206\14Cg\320$Q\222\6\315!"
-    "\33\62\212\10\31BD\206\215 v\320"
-    "\302\1x\24\312\272\205A\206\216\220@c\212\224\31$"
-    "S\14\262h\0\0\0\0\4\377\377\0";
-
-#define play_icon_width 14
-#define play_icon_height 14
-static const unsigned char play_icon[28] PROGMEM = {
-    0x00, 0x00, 0x00, 0x00, 0x3C, 0x00, 0x7C, 0x00, 0xFC, 0x00,
-    0xFC, 0x03, 0xFC, 0x0F, 0xFC, 0x0F, 0xFC, 0x03, 0xFC, 0x00,
-    0x7C, 0x00, 0x3C, 0x00, 0x00, 0x00, 0x00, 0x00};
-static const unsigned char pause_icon[28] PROGMEM = {
-    0x00, 0x00, 0x00, 0x00, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E,
-    0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E,
-    0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x00, 0x00};
-
-// Constants for screen layout and fonts
-constexpr uint8_t SCREEN_CENTER_X = 32;
-constexpr uint8_t MAIN_TEXT_Y = 26;
-constexpr uint8_t SUB_TEXT_Y = 40;
-constexpr uint8_t VISIBLE_MENU_ITEMS = 3;
-constexpr uint8_t MENU_ITEM_HEIGHT = 14;
-constexpr uint8_t MENU_BOX_PADDING = 4;
-constexpr uint8_t MENU_BOX_WIDTH = 64;
-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_RUN,
-  PARAM_MAIN_RESET,
-  PARAM_MAIN_SOURCE,
-  PARAM_MAIN_PULSE,
-  PARAM_MAIN_ENCODER_DIR,
-  PARAM_MAIN_ROTATE_DISP,
-  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_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);
-  int textWidth = gravity.display.getStrWidth(text);
-  gravity.display.drawStr(SCREEN_CENTER_X - (textWidth / 2), y, text);
-}
-
-// Helper function to draw right-aligned text
-void drawRightAlignedText(const char *text, int y) {
-  int textWidth = gravity.display.getStrWidth(text);
-  int drawX = (SCREEN_WIDTH - textWidth) - MENU_BOX_PADDING;
-  gravity.display.drawStr(drawX, y, text);
-}
-
-void drawMainSelection() {
-  gravity.display.setDrawColor(1);
-  const int tickSize = 3;
-  const int mainWidth = SCREEN_WIDTH / 2;
-  const int mainHeight = 49;
-  gravity.display.drawLine(0, 0, tickSize, 0);
-  gravity.display.drawLine(0, 0, 0, tickSize);
-  gravity.display.drawLine(mainWidth, 0, mainWidth - tickSize, 0);
-  gravity.display.drawLine(mainWidth, 0, mainWidth, tickSize);
-  gravity.display.drawLine(mainWidth, mainHeight, mainWidth,
-                           mainHeight - tickSize);
-  gravity.display.drawLine(mainWidth, mainHeight, mainWidth - tickSize,
-                           mainHeight);
-  gravity.display.drawLine(0, mainHeight, tickSize, mainHeight);
-  gravity.display.drawLine(0, mainHeight, 0, mainHeight - tickSize);
-  gravity.display.setDrawColor(2);
-}
-
-void drawMenuItems(String menu_items[], int menu_size) {
-  // Draw menu items
-  gravity.display.setFont(TEXT_FONT);
-
-  // Draw selected menu item box
-  int selectedBoxY = 0;
-  if (menu_size >= VISIBLE_MENU_ITEMS && app.selected_param == menu_size - 1) {
-    selectedBoxY = MENU_ITEM_HEIGHT * min(2, app.selected_param);
-  } else if (app.selected_param > 0) {
-    selectedBoxY = MENU_ITEM_HEIGHT;
-  }
-
-  int boxX = MENU_BOX_WIDTH + 1;
-  int boxY = selectedBoxY + 2;
-  int boxWidth = MENU_BOX_WIDTH - 1;
-  int boxHeight = MENU_ITEM_HEIGHT + 1;
-
-  if (app.editing_param) {
-    gravity.display.drawBox(boxX, boxY, boxWidth, boxHeight);
-    drawMainSelection();
-  } else {
-    gravity.display.drawFrame(boxX, boxY, boxWidth, boxHeight);
-  }
-
-  // Draw the visible menu items
-  int start_index = 0;
-  if (menu_size >= VISIBLE_MENU_ITEMS && app.selected_param == menu_size - 1) {
-    start_index = menu_size - VISIBLE_MENU_ITEMS;
-  } else if (app.selected_param > 0) {
-    start_index = app.selected_param - 1;
-  }
-
-  for (int i = 0; i < min(menu_size, VISIBLE_MENU_ITEMS); ++i) {
-    int idx = start_index + i;
-    drawRightAlignedText(menu_items[idx].c_str(),
-                         MENU_ITEM_HEIGHT * (i + 1) - 1);
-  }
-}
-
-// Visual indicators for main section of screen.
-inline void solidTick() { gravity.display.drawBox(56, 4, 4, 4); }
-inline void hollowTick() { gravity.display.drawBox(56, 4, 4, 4); }
-
-// Human friendly display value for save slot.
-String displaySaveSlot(int slot) {
-  if (slot >= 0 && slot < StateManager::MAX_SAVE_SLOTS / 2) {
-    return String("A") + String(slot + 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);
-  }
-}
-
-// Main display functions
-
-void DisplayMainPage() {
-  gravity.display.setFontMode(1);
-  gravity.display.setDrawColor(2);
-  gravity.display.setFont(TEXT_FONT);
-
-  // Display selected editable value
-  String mainText;
-  String subText;
-
-  switch (app.selected_param) {
-  case PARAM_MAIN_TEMPO:
-    // Serial MIDI is too unstable to display bpm in real time.
-    if (app.selected_source == Clock::SOURCE_EXTERNAL_MIDI) {
-      mainText = F("EXT");
-    } else {
-      mainText = String(gravity.clock.Tempo());
-    }
-    subText = F("BPM");
-    break;
-  case PARAM_MAIN_RUN:
-    mainText = F("RUN");
-    switch (app.cv_run) {
-    case 0:
-      subText = F("NONE");
-      break;
-    case 1:
-      subText = F("CV1 GATE");
-      break;
-    case 2:
-      subText = F("CV2 GATE");
-      break;
-    }
-    break;
-  case PARAM_MAIN_RESET:
-    mainText = F("RST");
-    switch (app.cv_reset) {
-    case 0:
-      subText = F("NONE");
-      break;
-    case 1:
-      subText = F("CV1 TRIG");
-      break;
-    case 2:
-      subText = F("CV2 TRIG");
-      break;
-    }
-    break;
-  case PARAM_MAIN_SOURCE:
-    mainText = F("EXT");
-    switch (app.selected_source) {
-    case Clock::SOURCE_INTERNAL:
-      mainText = F("INT");
-      subText = F("CLOCK");
-      break;
-    case Clock::SOURCE_EXTERNAL_PPQN_24:
-      subText = F("24 PPQN");
-      break;
-    case Clock::SOURCE_EXTERNAL_PPQN_4:
-      subText = F("4 PPQN");
-      break;
-    case Clock::SOURCE_EXTERNAL_PPQN_2:
-      subText = F("2 PPQN");
-      break;
-    case Clock::SOURCE_EXTERNAL_PPQN_1:
-      subText = F("1 PPQN");
-      break;
-    case Clock::SOURCE_EXTERNAL_MIDI:
-      subText = F("MIDI");
-      break;
-    }
-    break;
-  case PARAM_MAIN_PULSE:
-    mainText = F("OUT");
-    switch (app.selected_pulse) {
-    case Clock::PULSE_NONE:
-      subText = F("PULSE OFF");
-      break;
-    case Clock::PULSE_PPQN_24:
-      subText = F("24 PPQN PULSE");
-      break;
-    case Clock::PULSE_PPQN_4:
-      subText = F("4 PPQN PULSE");
-      break;
-    case Clock::PULSE_PPQN_1:
-      subText = F("1 PPQN PULSE");
-      break;
-    }
-    break;
-  case PARAM_MAIN_ENCODER_DIR:
-    mainText = F("DIR");
-    subText = app.selected_sub_param == 0 ? F("DEFAULT") : F("REVERSED");
-    break;
-  case PARAM_MAIN_ROTATE_DISP:
-    mainText = F("DISP");
-    subText = app.selected_sub_param == 0 ? F("DEFAULT") : F("ROTATED");
-    break;
-  case PARAM_MAIN_SAVE_DATA:
-  case PARAM_MAIN_LOAD_DATA:
-    if (app.selected_sub_param == StateManager::MAX_SAVE_SLOTS) {
-      mainText = F("x");
-      subText = F("BACK TO MAIN");
-    } else {
-      // Indicate currently active slot.
-      if (app.selected_sub_param == app.selected_save_slot) {
-        solidTick();
-      }
-      mainText = displaySaveSlot(app.selected_sub_param);
-      subText = (app.selected_param == PARAM_MAIN_SAVE_DATA)
-                    ? F("SAVE TO SLOT")
-                    : F("LOAD FROM SLOT");
-    }
-    break;
-  case PARAM_MAIN_RESET_STATE:
-    if (app.selected_sub_param == 0) {
-      mainText = F("RST");
-      subText = F("RESET ALL");
-    } else {
-      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("RUN"),         F("RST"),         F("SOURCE"),
-      F("PULSE OUT"), F("ENCODER DIR"), F("ROTATE DISP"), F("SAVE"),
-      F("LOAD"),      F("RESET"),       F("ERASE")};
-  drawMenuItems(menu_items, PARAM_MAIN_LAST);
-}
-
-void DisplayChannelPage() {
-  auto &ch = GetSelectedChannel();
-
-  gravity.display.setFontMode(1);
-  gravity.display.setDrawColor(2);
-
-  // Display selected editable value
-  String mainText;
-  String subText;
-
-  // When editing a param, just show the base value. When not editing show
-  // the value with cv mod.
-  bool withCvMod = !app.editing_param;
-
-  switch (app.selected_param) {
-  case PARAM_CH_MOD: {
-    int mod_value = ch.getClockMod(withCvMod);
-    if (mod_value > 1) {
-      mainText = F("/");
-      mainText += String(mod_value);
-      subText = F("DIVIDE");
-    } else {
-      mainText = F("x");
-      mainText += String(abs(mod_value));
-      subText = F("MULTIPLY");
-    }
-    break;
-  }
-
-  case PARAM_CH_EUC_STEPS:
-    mainText = String(ch.getSteps(withCvMod));
-    subText = "EUCLID STEPS";
-    break;
-  case PARAM_CH_EUC_HITS:
-    mainText = String(ch.getHits(withCvMod));
-    subText = "EUCLID HITS";
-    break;
-  case PARAM_CH_CV1_DEST:
-  case PARAM_CH_CV2_DEST: {
-    mainText = (app.selected_param == PARAM_CH_CV1_DEST) ? F("CV1") : F("CV2");
-    switch ((app.selected_param == PARAM_CH_CV1_DEST) ? ch.getCv1Dest()
-                                                      : ch.getCv2Dest()) {
-    case CV_DEST_NONE:
-      subText = F("NONE");
-      break;
-    case CV_DEST_MOD:
-      subText = F("CLOCK MOD");
-      break;
-
-    case CV_DEST_EUC_STEPS:
-      subText = F("EUCLID STEPS");
-      break;
-    case CV_DEST_EUC_HITS:
-      subText = F("EUCLID HITS");
-      break;
-    }
-    break;
-  }
-  }
-
-  drawCenteredText(mainText.c_str(), MAIN_TEXT_Y, LARGE_FONT);
-  drawCenteredText(subText.c_str(), SUB_TEXT_Y, TEXT_FONT);
-
-  // Draw Channel Page menu items
-  String menu_items[PARAM_CH_LAST] = {F("MOD"), F("EUCLID STEPS"),
-                                      F("EUCLID HITS"), F("CV1 MOD"),
-                                      F("CV2 MOD")};
-  drawMenuItems(menu_items, PARAM_CH_LAST);
-}
-
-void DisplaySelectedChannel() {
-  int boxX = CHANNEL_BOX_WIDTH;
-  int boxY = CHANNEL_BOXES_Y;
-  int boxWidth = CHANNEL_BOX_WIDTH;
-  int boxHeight = CHANNEL_BOX_HEIGHT;
-  int textOffset = 7; // Half of font width
-
-  // Draw top and right side of frame.
-  gravity.display.drawHLine(1, boxY, SCREEN_WIDTH - 2);
-  gravity.display.drawVLine(SCREEN_WIDTH - 2, boxY, boxHeight);
-
-  for (int i = 0; i < Gravity::OUTPUT_COUNT + 1; i++) {
-    // Draw box frame or filled selected box.
-    gravity.display.setDrawColor(1);
-    (app.selected_channel == i)
-        ? gravity.display.drawBox(i * boxWidth, boxY, boxWidth, boxHeight)
-        : gravity.display.drawVLine(i * boxWidth, boxY, boxHeight);
-
-    // Draw clock status icon or each channel number.
-    gravity.display.setDrawColor(2);
-    if (i == 0) {
-      gravity.display.setBitmapMode(1);
-      auto icon = gravity.clock.IsPaused() ? pause_icon : play_icon;
-      gravity.display.drawXBMP(2, boxY, play_icon_width, play_icon_height,
-                               icon);
-    } else {
-      gravity.display.setFont(TEXT_FONT);
-      gravity.display.setCursor((i * boxWidth) + textOffset, SCREEN_HEIGHT - 3);
-      gravity.display.print(i);
-    }
-  }
-}
-
-void UpdateDisplay() {
-  app.refresh_screen = false;
-  gravity.display.firstPage();
-  do {
-    if (app.selected_channel == 0) {
-      DisplayMainPage();
-    } else {
-      DisplayChannelPage();
-    }
-    // Global channel select UI.
-    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());
-}
-
-#endif // DISPLAY_H

firmware/Euclidean/save_state.cpp

@@ -1,237 +0,0 @@
-/**
- * @file save_state.cpp
- * @author Adam Wonak (https://github.com/awonak/)
- * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version 2.0.1
- * @date 2025-07-04
- *
- * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
- *
- */
-
-#include "save_state.h"
-
-#include <EEPROM.h>
-
-#include "app_state.h"
-
-// Define the constants for the current firmware.
-const char StateManager::SKETCH_NAME[] = "ALT EUCLIDEAN";
-const char StateManager::SEMANTIC_VERSION[] =
-    "V2.0.1BETA1"; // 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.
-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) {
-  noInterrupts();
-  bool success = false;
-  if (_isDataValid()) {
-    // Load global settings.
-    _loadMetadata(app);
-    // Load app data from the transient slot.
-    _loadState(app, TRANSIENT_SLOT);
-    success = 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);
-  }
-  interrupts();
-  return success;
-}
-
-bool StateManager::loadData(AppState &app, byte slot_index) {
-  // Check if slot_index is within max range + 1 for transient.
-  if (slot_index >= MAX_SAVE_SLOTS + 1)
-    return false;
-
-  noInterrupts();
-
-  // 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 on next update.
-  _isDirty = true;
-
-  interrupts();
-  return true;
-}
-
-// Save app state to user specified save slot.
-void StateManager::saveData(const AppState &app) {
-  noInterrupts();
-  // Check if slot_index is within max range + 1 for transient.
-  if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1) {
-    interrupts();
-    return;
-  }
-
-  _saveState(app, app.selected_save_slot);
-  _saveMetadata(app);
-  _isDirty = false;
-  interrupts();
-}
-
-// 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)) {
-    noInterrupts();
-    _saveState(app, TRANSIENT_SLOT);
-    _saveMetadata(app);
-    _isDirty = false;
-    interrupts();
-  }
-}
-
-void StateManager::reset(AppState &app) {
-  noInterrupts();
-
-  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;
-  app.cv_run = default_app.cv_run;
-  app.cv_reset = default_app.cv_reset;
-
-  for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    app.channel[i].Init();
-  }
-
-  // Load global settings from Metadata
-  _loadMetadata(app);
-
-  _isDirty = false;
-  interrupts();
-}
-
-void StateManager::markDirty() {
-  _isDirty = true;
-  _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 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) {
-  // Check if slot_index is within max range + 1 for transient.
-  if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1)
-    return;
-
-  static EepromData save_data;
-
-  save_data.tempo = app.tempo;
-  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.cv_run = app.cv_run;
-  save_data.cv_reset = app.cv_reset;
-
-  // 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];
-    save_ch.base_clock_mod_index = ch.getClockModIndex(false);
-    save_ch.base_euc_steps = ch.getSteps(false);
-    save_ch.base_euc_hits = ch.getHits(false);
-    save_ch.cv1_dest = static_cast<byte>(ch.getCv1Dest());
-    save_ch.cv2_dest = static_cast<byte>(ch.getCv2Dest());
-  }
-
-  int address = EEPROM_DATA_START_ADDR + (slot_index * sizeof(EepromData));
-  EEPROM.put(address, save_data);
-}
-
-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;
-
-  static EepromData load_data;
-  int address = EEPROM_DATA_START_ADDR + (slot_index * sizeof(EepromData));
-  EEPROM.get(address, load_data);
-
-  // Restore app state from loaded data.
-  app.tempo = load_data.tempo;
-  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.cv_run = load_data.cv_run;
-  app.cv_reset = load_data.cv_reset;
-
-  for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    auto &ch = app.channel[i];
-    const auto &saved_ch_state = load_data.channel_data[i];
-
-    ch.setClockMod(saved_ch_state.base_clock_mod_index);
-    ch.setSteps(saved_ch_state.base_euc_steps);
-    ch.setHits(saved_ch_state.base_euc_hits);
-    ch.setCv1Dest(static_cast<CvDestination>(saved_ch_state.cv1_dest));
-    ch.setCv2Dest(static_cast<CvDestination>(saved_ch_state.cv2_dest));
-  }
-}
-
-void StateManager::_saveMetadata(const AppState &app) {
-  Metadata current_meta;
-  strcpy(current_meta.sketch_name, SKETCH_NAME);
-  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;
-  current_meta.rotate_display = app.rotate_display;
-
-  EEPROM.put(METADATA_START_ADDR, current_meta);
-}
-
-void StateManager::_loadMetadata(AppState &app) {
-  Metadata metadata;
-  EEPROM.get(METADATA_START_ADDR, metadata);
-  app.selected_save_slot = metadata.selected_save_slot;
-  app.encoder_reversed = metadata.encoder_reversed;
-  app.rotate_display = metadata.rotate_display;
-}

firmware/Euclidean/save_state.h

@@ -1,96 +0,0 @@
-/**
- * @file save_state.h
- * @author Adam Wonak (https://github.com/awonak/)
- * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version 2.0.1
- * @date 2025-07-04
- *
- * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
- *
- */
-
-#ifndef SAVE_STATE_H
-#define SAVE_STATE_H
-
-#include <Arduino.h>
-#include <libGravity.h>
-
-// Forward-declare AppState to avoid circular dependencies.
-struct AppState;
-
-/**
- * @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 is reseved for transient state to persist state between power
- * cycles before state is explicitly saved to a user slot. Metadata is stored in
- * the beginning of the memory space which stores firmware version information
- * to validate that the data can be loaded into the current version of AppState.
- */
-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.
-  bool initialize(AppState &app);
-  // Load data from specified slot.
-  bool loadData(AppState &app, byte slot_index);
-  // Save data to specified slot.
-  void saveData(const AppState &app);
-  // Reset AppState instance back to default values.
-  void reset(AppState &app);
-  // Call from main loop, check if state has changed and needs to be saved.
-  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 {
-    char sketch_name[16];
-    char version[16];
-    // Additional global/hardware settings
-    byte selected_save_slot;
-    bool encoder_reversed;
-    bool rotate_display;
-  };
-  struct ChannelState {
-    byte base_clock_mod_index;
-    byte base_euc_steps;
-    byte base_euc_hits;
-    byte cv1_dest; // Cast the CvDestination enum as a byte for storage
-    byte cv2_dest; // Cast the CvDestination enum as a byte for storage
-  };
-  // This struct holds all the parameters we want to save.
-  struct EepromData {
-    int tempo;
-    byte selected_param;
-    byte selected_channel;
-    byte selected_source;
-    byte selected_pulse;
-    byte cv_run;
-    byte cv_reset;
-    ChannelState channel_data[Gravity::OUTPUT_COUNT];
-  };
-
-private:
-  bool _isDataValid();
-  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;
-};
-
-#endif // SAVE_STATE_H

firmware/Gravity/Gravity.ino

@@ -2,10 +2,11 @@
  * @file Gravity.ino
  * @author Adam Wonak (https://github.com/awonak/)
  * @brief Alt firmware version of Gravity by Sitka Instruments.
- * @version v2.0.1beta1 - February 2026 awonak
+ * @version v2.0.0 - June 2025 awonak - Full rewrite
- * @date 2026-02-21
+ * @version v1.0 - August 2023 Oleksiy H - Initial release
+ * @date 2025-07-04
  *
- * @copyright MIT - (c) 2026 - Adam Wonak - adam.wonak@gmail.com
+ * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
  *
  * This version of Gravity firmware is a full rewrite that leverages the
  * libGravity hardware abstraction library. The goal of this project was to
@@ -33,20 +34,17 @@
  *      Play/pause - start or stop the internal clock.
  *
  * BTN2:
- *      Shift - hold and rotate encoder to change current selected output
+ *      Shift - hold and rotate encoder to change current selected output channel.
- * channel.
  *
  * EXT:
  *      External clock input. When Gravity is set to INTERNAL or MIDI clock
  *      source, this input is used to reset clocks.
  *
  * CV1:
- *      External analog input used to provide modulation to any channel
+ *      External analog input used to provide modulation to any channel parameter.
- * parameter.
  *
  * CV2:
- *      External analog input used to provide modulation to any channel
+ *      External analog input used to provide modulation to any channel parameter.
- * parameter.
  *
  */
 
@@ -93,40 +91,8 @@ void loop() {
     // Process change in state of inputs and outputs.
     gravity.Process();
 
-  // Read CVs and call the update function for each channel.
+    // Check if cv run or reset is active and read cv.
-  int cv1 = gravity.cv1.Read();
+    CheckRunReset(gravity.cv1, gravity.cv2);
-  int cv2 = gravity.cv2.Read();
-
-  for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    auto &ch = app.channel[i];
-    // Only apply CV to the channel when the current channel has cv
-    // mod configured.
-    if (ch.isCvModActive()) {
-      ch.applyCvMod(cv1, cv2);
-    }
-  }
-
-  // Clock Run
-  if (app.cv_run == 1 || app.cv_run == 2) {
-    auto &cv = app.cv_run == 1 ? gravity.cv1 : gravity.cv2;
-    int val = cv.Read();
-    if (val > AnalogInput::GATE_THRESHOLD && gravity.clock.IsPaused()) {
-      gravity.clock.Start();
-      app.refresh_screen = true;
-    } else if (val < AnalogInput::GATE_THRESHOLD && !gravity.clock.IsPaused()) {
-      gravity.clock.Stop();
-      ResetOutputs();
-      app.refresh_screen = true;
-    }
-  }
-
-  // Clock Reset
-  if ((app.cv_reset == 1 &&
-       gravity.cv1.IsRisingEdge(AnalogInput::GATE_THRESHOLD)) ||
-      (app.cv_reset == 2 &&
-       gravity.cv2.IsRisingEdge(AnalogInput::GATE_THRESHOLD))) {
-    gravity.clock.Reset();
-  }
 
     // Check for dirty state eligible to be saved.
     stateManager.update(app);
@@ -165,8 +131,7 @@ void HandleIntClockTick(uint32_t tick) {
                 break;
         }
 
-    const uint16_t pulse_high_ticks =
+        const uint16_t pulse_high_ticks = pgm_read_word_near(&CLOCK_MOD_PULSES[clock_index]);
-        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) {
@@ -196,6 +161,27 @@ void HandleExtClockTick() {
     app.refresh_screen = true;
 }
 
+void CheckRunReset(AnalogInput& cv1, AnalogInput& cv2) {
+    // Clock Run
+    if (app.cv_run == 1 || app.cv_run == 2) {
+        const int val = (app.cv_run == 1) ? cv1.Read() : cv2.Read();
+        if (val > AnalogInput::GATE_THRESHOLD && gravity.clock.IsPaused()) {
+            gravity.clock.Start();
+            app.refresh_screen = true;
+        } else if (val < AnalogInput::GATE_THRESHOLD && !gravity.clock.IsPaused()) {
+            gravity.clock.Stop();
+            ResetOutputs();
+            app.refresh_screen = true;
+        }
+    }
+
+    // Clock Reset
+    if ((app.cv_reset == 1 && cv1.IsRisingEdge(AnalogInput::GATE_THRESHOLD)) ||
+        (app.cv_reset == 2 && cv2.IsRisingEdge(AnalogInput::GATE_THRESHOLD))) {
+        gravity.clock.Reset();
+    }
+}
+
 //
 // UI handlers for encoder and buttons.
 //
@@ -210,13 +196,15 @@ void HandlePlayPressed() {
             }
         } else {
             // Mute selected channel
-      auto &ch = GetSelectedChannel();
+            auto& ch = GetSelectedChannel();
             ch.toggleMute();
         }
         return;
     }
 
-  gravity.clock.IsPaused() ? gravity.clock.Start() : gravity.clock.Stop();
+    gravity.clock.IsPaused()
+        ? gravity.clock.Start()
+        : gravity.clock.Stop();
     ResetOutputs();
     app.refresh_screen = true;
 }
@@ -230,10 +218,6 @@ void HandleEncoderPressed() {
                 app.encoder_reversed = app.selected_sub_param == 1;
                 gravity.encoder.SetReverseDirection(app.encoder_reversed);
             }
-      if (app.selected_param == PARAM_MAIN_ROTATE_DISP) {
-        app.rotate_display = app.selected_sub_param == 1;
-        gravity.display.setFlipMode(app.rotate_display ? 1 : 0);
-      }
             if (app.selected_param == PARAM_MAIN_SAVE_DATA) {
                 if (app.selected_sub_param < StateManager::MAX_SAVE_SLOTS) {
                     app.selected_save_slot = app.selected_sub_param;
@@ -243,21 +227,7 @@ void HandleEncoderPressed() {
             if (app.selected_param == PARAM_MAIN_LOAD_DATA) {
                 if (app.selected_sub_param < StateManager::MAX_SAVE_SLOTS) {
                     app.selected_save_slot = app.selected_sub_param;
-          // Load pattern data into app state.
                     stateManager.loadData(app, app.selected_save_slot);
-          // Load global performance settings if they have changed.
-          if (gravity.clock.Tempo() != app.tempo) {
-            gravity.clock.SetTempo(app.tempo);
-          }
-          // Load global settings only if clock is not active.
-          if (gravity.clock.IsPaused()) {
-            InitGravity(app);
-          }
-        }
-      }
-      if (app.selected_param == PARAM_MAIN_RESET_STATE) {
-        if (app.selected_sub_param == 0) { // Reset
-          stateManager.reset(app);
                     InitGravity(app);
                 }
             }
@@ -288,8 +258,7 @@ void HandleRotate(int val) {
 
     if (!app.editing_param) {
         // Navigation Mode
-    const int max_param =
+        const int max_param = (app.selected_channel == 0) ? PARAM_MAIN_LAST : PARAM_CH_LAST;
-        (app.selected_channel == 0) ? PARAM_MAIN_LAST : PARAM_CH_LAST;
         updateSelection(app.selected_param, val, max_param);
     } else {
         // Editing Mode
@@ -346,16 +315,9 @@ void editMainParameter(int val) {
         case PARAM_MAIN_ENCODER_DIR:
             updateSelection(app.selected_sub_param, val, 2);
             break;
-  case PARAM_MAIN_ROTATE_DISP:
-    updateSelection(app.selected_sub_param, val, 2);
-    break;
         case PARAM_MAIN_SAVE_DATA:
         case PARAM_MAIN_LOAD_DATA:
-    updateSelection(app.selected_sub_param, val,
+            updateSelection(app.selected_sub_param, val, StateManager::MAX_SAVE_SLOTS + 1);
-                    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);
@@ -364,7 +326,7 @@ void editMainParameter(int val) {
 }
 
 void editChannelParameter(int val) {
-  auto &ch = GetSelectedChannel();
+    auto& ch = GetSelectedChannel();
     switch (app.selected_param) {
         case PARAM_CH_MOD:
             ch.setClockMod(ch.getClockModIndex() + val);
@@ -381,6 +343,12 @@ void editChannelParameter(int val) {
         case PARAM_CH_SWING:
             ch.setSwing(ch.getSwing() + val);
             break;
+        case PARAM_CH_EUC_STEPS:
+            ch.setSteps(ch.getSteps() + val);
+            break;
+        case PARAM_CH_EUC_HITS:
+            ch.setHits(ch.getHits() + val);
+            break;
         case PARAM_CH_CV1_DEST: {
             byte dest = static_cast<int>(ch.getCv1Dest());
             updateSelection(dest, val, CV_DEST_LAST);
@@ -397,7 +365,7 @@ void editChannelParameter(int val) {
 }
 
 // Changes the param by the value provided.
-void updateSelection(byte &param, int change, int maxValue) {
+void updateSelection(byte& param, int change, int maxValue) {
     // Do not apply acceleration if max value is less than 25.
     if (maxValue < 25) {
         change = change > 0 ? 1 : -1;
@@ -409,11 +377,10 @@ void updateSelection(byte &param, int change, int maxValue) {
 // App Helper functions.
 //
 
-void InitGravity(AppState &app) {
+void InitGravity(AppState& app) {
     gravity.clock.SetTempo(app.tempo);
     gravity.clock.SetSource(app.selected_source);
     gravity.encoder.SetReverseDirection(app.encoder_reversed);
-  gravity.display.setFlipMode(app.rotate_display ? 1 : 0);
 }
 
 void ResetOutputs() {

firmware/Gravity/app_state.h

@@ -31,13 +31,12 @@ struct AppState {
     Clock::Pulse selected_pulse = Clock::PULSE_PPQN_24;
     bool editing_param = false;
     bool encoder_reversed = false;
-  bool rotate_display = false;
     bool refresh_screen = true;
 };
 
 extern AppState app;
 
-static Channel &GetSelectedChannel() {
+static Channel& GetSelectedChannel() {
     return app.channel[app.selected_channel - 1];
 }
 

firmware/Gravity/channel.h

@@ -15,6 +15,8 @@
 #include <Arduino.h>
 #include <libGravity.h>
 
+#include "euclidean.h"
+
 // Enums for CV Mod destination
 enum CvDestination : uint8_t {
     CV_DEST_NONE,
@@ -23,6 +25,8 @@ enum CvDestination : uint8_t {
     CV_DEST_DUTY,
     CV_DEST_OFFSET,
     CV_DEST_SWING,
+    CV_DEST_EUC_STEPS,
+    CV_DEST_EUC_HITS,
     CV_DEST_LAST,
 };
 
@@ -41,8 +45,7 @@ static const int CLOCK_MOD[MOD_CHOICE_SIZE] PROGMEM = {
 // that match the above div/mult mods.
 static const int CLOCK_MOD_PULSES[MOD_CHOICE_SIZE] PROGMEM = {
     // Divisor Pulses (96 * X)
-    12288, 6144, 3072, 2304, 1536, 1152, 1056, 960, 864, 768, 672, 576, 480,
+    12288, 6144, 3072, 2304, 1536, 1152, 1056, 960, 864, 768, 672, 576, 480, 384, 288, 192,
-    384, 288, 192,
     // Internal Clock Pulses
     96,
     // Multiplier Pulses (96 / X)
@@ -55,8 +58,10 @@ 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:
+   public:
-  Channel() { Init(); }
+    Channel() {
+        Init();
+    }
 
     void Init() {
         // Reset base values to their defaults
@@ -66,107 +71,133 @@ public:
         base_offset = 0;
         base_swing = 50;
 
-    cvmod_clock_mod_index = base_clock_mod_index;
-    cvmod_probability = base_probability;
-    cvmod_duty_cycle = base_duty_cycle;
-    cvmod_offset = base_offset;
-    cvmod_swing = base_swing;
-
         cv1_dest = CV_DEST_NONE;
         cv2_dest = CV_DEST_NONE;
 
+        pattern.Init(DEFAULT_PATTERN);
+
         // Calcule the clock mod pulses on init.
         _recalculatePulses();
     }
 
+    bool isCvModActive() const { return cv1_dest != CV_DEST_NONE || cv2_dest != CV_DEST_NONE; }
+
     // Setters (Set the BASE value)
 
     void setClockMod(int index) {
         base_clock_mod_index = constrain(index, 0, MOD_CHOICE_SIZE - 1);
-    if (!isCvModActive()) {
-      cvmod_clock_mod_index = base_clock_mod_index;
-      _recalculatePulses();
-    }
     }
 
     void setProbability(int prob) {
         base_probability = constrain(prob, 0, 100);
-    if (!isCvModActive()) {
-      cvmod_probability = base_probability;
-      _recalculatePulses();
-    }
     }
 
     void setDutyCycle(int duty) {
         base_duty_cycle = constrain(duty, 1, 99);
-    if (!isCvModActive()) {
-      cvmod_duty_cycle = base_duty_cycle;
-      _recalculatePulses();
-    }
     }
 
     void setOffset(int off) {
         base_offset = constrain(off, 0, 99);
-    if (!isCvModActive()) {
-      cvmod_offset = base_offset;
-      _recalculatePulses();
-    }
     }
     void setSwing(int val) {
         base_swing = constrain(val, 50, 95);
-    if (!isCvModActive()) {
-      cvmod_swing = base_swing;
-      _recalculatePulses();
-    }
     }
 
-  void setCv1Dest(CvDestination dest) { cv1_dest = dest; }
+    // Euclidean
-  void setCv2Dest(CvDestination dest) { cv2_dest = dest; }
+    void setSteps(int val) {
+        pattern.SetSteps(val);
+    }
+    void setHits(int val) {
+        pattern.SetHits(val);
+    }
+
+    void setCv1Dest(CvDestination dest) {
+        cv1_dest = dest;
+        _recalculatePulses();
+    }
+    void setCv2Dest(CvDestination dest) {
+        cv2_dest = dest;
+        _recalculatePulses();
+    }
     CvDestination getCv1Dest() const { return cv1_dest; }
     CvDestination getCv2Dest() const { return cv2_dest; }
 
     // Getters (Get the BASE value for editing or cv modded value for display)
+    int getProbability() const { return base_probability; }
+    int getDutyCycle() const { return base_duty_cycle; }
+    int getOffset() const { return base_offset; }
+    int getSwing() const { return base_swing; }
+    int getClockMod() const { return pgm_read_word_near(&CLOCK_MOD[getClockModIndex()]); }
+    int getClockModIndex() const { return base_clock_mod_index; }
+    byte getSteps() const { return pattern.GetSteps(); }
+    byte getHits() const { return pattern.GetHits(); }
 
-  int getProbability(bool withCvMod = false) const {
+    // Getters that calculate the value with CV modulation applied.
-    return withCvMod ? cvmod_probability : base_probability;
+    int getClockModIndexWithMod(int cv1_val, int cv2_val) {
+        int clock_mod_index = _calculateMod(CV_DEST_MOD, cv1_val, cv2_val, -(MOD_CHOICE_SIZE / 2), MOD_CHOICE_SIZE / 2);
+        return constrain(base_clock_mod_index + clock_mod_index, 0, MOD_CHOICE_SIZE - 1);
     }
-  int getDutyCycle(bool withCvMod = false) const {
+
-    return withCvMod ? cvmod_duty_cycle : base_duty_cycle;
+    int getClockModWithMod(int cv1_val, int cv2_val) {
+        int clock_mod = _calculateMod(CV_DEST_MOD, cv1_val, cv2_val, -(MOD_CHOICE_SIZE / 2), MOD_CHOICE_SIZE / 2);
+        return pgm_read_word_near(&CLOCK_MOD[getClockModIndexWithMod(cv1_val, cv2_val)]);
     }
-  int getOffset(bool withCvMod = false) const {
+
-    return withCvMod ? cvmod_offset : base_offset;
+    int getProbabilityWithMod(int cv1_val, int cv2_val) {
+        int prob_mod = _calculateMod(CV_DEST_PROB, cv1_val, cv2_val, -50, 50);
+        return constrain(base_probability + prob_mod, 0, 100);
     }
-  int getSwing(bool withCvMod = false) const {
+
-    return withCvMod ? cvmod_swing : base_swing;
+    int getDutyCycleWithMod(int cv1_val, int cv2_val) {
+        int duty_mod = _calculateMod(CV_DEST_DUTY, cv1_val, cv2_val, -50, 50);
+        return constrain(base_duty_cycle + duty_mod, 1, 99);
     }
-  int getClockMod(bool withCvMod = false) const {
+
-    return pgm_read_word_near(&CLOCK_MOD[getClockModIndex(withCvMod)]);
+    int getOffsetWithMod(int cv1_val, int cv2_val) {
+        int offset_mod = _calculateMod(CV_DEST_OFFSET, cv1_val, cv2_val, -50, 50);
+        return constrain(base_offset + offset_mod, 0, 99);
     }
-  int getClockModIndex(bool withCvMod = false) const {
+
-    return withCvMod ? cvmod_clock_mod_index : base_clock_mod_index;
+    int getSwingWithMod(int cv1_val, int cv2_val) {
+        int swing_mod = _calculateMod(CV_DEST_SWING, cv1_val, cv2_val, -25, 25);
+        return constrain(base_swing + swing_mod, 50, 95);
     }
-  bool isCvModActive() const {
+
-    return cv1_dest != CV_DEST_NONE || cv2_dest != CV_DEST_NONE;
+    byte getStepsWithMod(int cv1_val, int cv2_val) {
+        int step_mod = _calculateMod(CV_DEST_EUC_STEPS, cv1_val, cv2_val, 0, MAX_PATTERN_LEN);
+        return constrain(pattern.GetSteps() + step_mod, 1, MAX_PATTERN_LEN);
+    }
+
+    byte getHitsWithMod(int cv1_val, int cv2_val) {
+        // The number of hits is dependent on the modulated number of steps.
+        byte modulated_steps = getStepsWithMod(cv1_val, cv2_val);
+        int hit_mod = _calculateMod(CV_DEST_EUC_HITS, cv1_val, cv2_val, 0, modulated_steps);
+        return constrain(pattern.GetHits() + hit_mod, 1, modulated_steps);
     }
 
     void toggleMute() { mute = !mute; }
 
     /**
-   * @brief Processes a clock tick and determines if the output should be high
+     * @brief Processes a clock tick and determines if the output should be high or low.
-   * or low. Note: this method is called from an ISR and must be kept as simple
+     * Note: this method is called from an ISR and must be kept as simple as possible.
-   * as possible.
      * @param tick The current clock tick count.
      * @param output The output object to be modified.
      */
-  void processClockTick(uint32_t tick, DigitalOutput &output) {
+    void processClockTick(uint32_t tick, DigitalOutput& output) {
         // Mute check
         if (mute) {
             output.Low();
             return;
         }
 
-    const uint16_t mod_pulses =
+        if (isCvModActive()) _recalculatePulses();
-        pgm_read_word_near(&CLOCK_MOD_PULSES[cvmod_clock_mod_index]);
+
+        int cv1 = gravity.cv1.Read();
+        int cv2 = gravity.cv2.Read();
+        int cvmod_clock_mod_index = getClockModIndexWithMod(cv1, cv2);
+        int cvmod_probability = getProbabilityWithMod(cv1, cv2);
+
+        const uint16_t mod_pulses = pgm_read_word_near(&CLOCK_MOD_PULSES[cvmod_clock_mod_index]);
 
         // Conditionally apply swing on down beats.
         uint16_t swing_pulses = 0;
@@ -180,6 +211,15 @@ public:
             // Step check
             if (current_tick_offset % mod_pulses == 0) {
                 bool hit = cvmod_probability >= random(0, 100);
+                // Euclidean rhythm hit check
+                switch (pattern.NextStep()) {
+                    case Pattern::REST:  // Rest when active or fall back to probability
+                        hit = false;
+                        break;
+                    case Pattern::HIT:  // Hit if probability is true
+                        hit &= true;
+                        break;
+                }
                 if (hit) {
                     output.High();
                 }
@@ -187,80 +227,34 @@ public:
         }
 
         // Duty cycle low check
-    const uint32_t duty_cycle_end_tick =
+        const uint32_t duty_cycle_end_tick = tick + _duty_pulses + _offset_pulses + swing_pulses;
-        tick + _duty_pulses + _offset_pulses + swing_pulses;
         if (duty_cycle_end_tick % mod_pulses == 0) {
             output.Low();
         }
     }
-  /**
-   * @brief Calculate and store cv modded values using bipolar mapping.
-   * Default to base value if not the current CV destination.
-   *
-   * @param cv1_val analog input reading for cv1
-   * @param cv2_val analog input reading for cv2
-   *
-   */
-  void applyCvMod(int cv1_val, int cv2_val) {
-    // Note: This is optimized for cpu performance. This method is called
-    // from the main loop and stores the cv mod values. This reduces CPU
-    // cycles inside the internal clock interrupt, which is preferrable.
-    // However, if RAM usage grows too much, we have an opportunity to
-    // refactor this to store just the CV read values, and calculate the
-    // cv mod value per channel inside the getter methods by passing cv
-    // values. This would reduce RAM usage, but would introduce a
-    // significant CPU cost, which may have undesirable performance issues.
-    if (!isCvModActive()) {
-      cvmod_clock_mod_index = base_clock_mod_index;
-      cvmod_probability = base_clock_mod_index;
-      cvmod_duty_cycle = base_clock_mod_index;
-      cvmod_offset = base_clock_mod_index;
-      cvmod_swing = base_clock_mod_index;
-      return;
-    }
 
-    int dest_mod = _calculateMod(CV_DEST_MOD, cv1_val, cv2_val,
+   private:
-                                 -(MOD_CHOICE_SIZE / 2), MOD_CHOICE_SIZE / 2);
+    int _calculateMod(CvDestination dest, int cv1_val, int cv2_val, int min_range, int max_range) {
-    cvmod_clock_mod_index = constrain(base_clock_mod_index + dest_mod, 0, 100);
+        int mod1 = (cv1_dest == dest) ? map(cv1_val, -512, 512, min_range, max_range) : 0;
-
+        int mod2 = (cv2_dest == dest) ? map(cv2_val, -512, 512, min_range, max_range) : 0;
-    int prob_mod = _calculateMod(CV_DEST_PROB, cv1_val, cv2_val, -50, 50);
-    cvmod_probability = constrain(base_probability + prob_mod, 0, 100);
-
-    int duty_mod = _calculateMod(CV_DEST_DUTY, cv1_val, cv2_val, -50, 50);
-    cvmod_duty_cycle = constrain(base_duty_cycle + duty_mod, 1, 99);
-
-    int offset_mod = _calculateMod(CV_DEST_OFFSET, cv1_val, cv2_val, -50, 50);
-    cvmod_offset = constrain(base_offset + offset_mod, 0, 99);
-
-    int swing_mod = _calculateMod(CV_DEST_SWING, cv1_val, cv2_val, -25, 25);
-    cvmod_swing = constrain(base_swing + swing_mod, 50, 95);
-
-    // After all cvmod values are updated, recalculate clock pulse modifiers.
-    _recalculatePulses();
-  }
-
-private:
-  int _calculateMod(CvDestination dest, int cv1_val, int cv2_val, int min_range,
-                    int max_range) {
-    int mod1 =
-        (cv1_dest == dest) ? map(cv1_val, -512, 512, min_range, max_range) : 0;
-    int mod2 =
-        (cv2_dest == dest) ? map(cv2_val, -512, 512, min_range, max_range) : 0;
         return mod1 + mod2;
     }
 
     void _recalculatePulses() {
-    const uint16_t mod_pulses =
+        int cv1 = gravity.cv1.Read();
-        pgm_read_word_near(&CLOCK_MOD_PULSES[cvmod_clock_mod_index]);
+        int cv2 = gravity.cv2.Read();
-    _duty_pulses =
+        int clock_mod_index = getClockModIndexWithMod(cv1, cv2);
-        max((long)((mod_pulses * (100L - cvmod_duty_cycle)) / 100L), 1L);
+        int duty_cycle = getDutyCycleWithMod(cv1, cv2);
-    _offset_pulses = (long)((mod_pulses * (100L - cvmod_offset)) / 100L);
+        int offset = getOffsetWithMod(cv1, cv2);
+        int swing = getSwingWithMod(cv1, cv2);
+        const uint16_t mod_pulses = pgm_read_word_near(&CLOCK_MOD_PULSES[clock_mod_index]);
+        _duty_pulses = max((long)((mod_pulses * (100L - duty_cycle)) / 100L), 1L);
+        _offset_pulses = (long)((mod_pulses * (100L - offset)) / 100L);
 
         // Calculate the down beat swing amount.
-    if (cvmod_swing > 50) {
+        if (swing > 50) {
-      int shifted_swing = cvmod_swing - 50;
+            int shifted_swing = swing - 50;
-      _swing_pulse_amount =
+            _swing_pulse_amount = (long)((mod_pulses * (100L - shifted_swing)) / 100L);
-          (long)((mod_pulses * (100L - shifted_swing)) / 100L);
         } else {
             _swing_pulse_amount = 0;
         }
@@ -273,17 +267,13 @@ private:
     byte base_offset;
     byte base_swing;
 
-  // Base value with cv mod applied.
-  byte cvmod_clock_mod_index;
-  byte cvmod_probability;
-  byte cvmod_duty_cycle;
-  byte cvmod_offset;
-  byte cvmod_swing;
-
     // CV mod configuration
     CvDestination cv1_dest;
     CvDestination cv2_dest;
 
+    // Euclidean pattern
+    Pattern pattern;
+
     // Mute channel flag
     bool mute;
 

firmware/Gravity/display.h

@@ -29,24 +29,17 @@
 const uint8_t TEXT_FONT[437] U8G2_FONT_SECTION("velvetscreen") PROGMEM =
     "\64\0\2\2\3\3\2\3\4\5\5\0\0\5\0\5\0\0\221\0\0\1\230 \4\200\134%\11\255tT"
     "R\271RI(\6\252\334T\31)\7\252\134bJ\12+\7\233\345\322J\0,\5\221T\4-\5\213"
-    "f\6.\5\211T\2/"
+    "f\6.\5\211T\2/\6\244\354c\33\60\10\254\354T\64\223\2\61\7\353\354\222\254\6\62\11\254l"
-    "\6\244\354c\33\60\10\254\354T\64\223\2\61\7\353\354\222\254\6\62\11\254l"
+    "\66J*\217\0\63\11\254l\66J\32\215\4\64\10\254l\242\34\272\0\65\11\254l\206\336h$\0\66"
-    "\66J*"
+    "\11\254\354T^\61)\0\67\10\254lF\216u\4\70\11\254\354TL*&\5\71\11\254\354TL;"
-    "\217\0\63\11\254l\66J\32\215\4\64\10\254l\242\34\272\0\65\11\254l\206\336h"
-    "$\0\66"
-    "\11\254\354T^\61)\0\67\10\254lF\216u\4\70\11\254\354TL*&"
-    "\5\71\11\254\354TL;"
     ")\0:\6\231UR\0A\10\254\354T\34S\6B\11\254lV\34)\216\4C\11\254\354T\324\61"
     ")\0D\10\254lV\64G\2E\10\254l\206\36z\4F\10\254l\206^\71\3G\11\254\354TN"
-    "\63)"
+    "\63)\0H\10\254l\242\34S\6I\6\251T\206\0J\10\254\354k\231\24\0K\11\254l\242J\62"
-    "\0H\10\254l\242\34S\6I\6\251T\206\0J\10\254\354k\231\24\0K\11\254l\242J\62"
     "\225\1L\7\254lr{\4M\11\255t\362ZI\353\0N\11\255t\362TI\356\0O\10\254\354T"
-    "\64\223\2P\11\254lV\34)"
+    "\64\223\2P\11\254lV\34)g\0Q\10\254\354T\264b\12R\10\254lV\34\251\31S\11\254\354"
-    "g\0Q\10\254\354T\264b\12R\10\254lV\34\251\31S\11\254\354"
     "FF\32\215\4T\7\253dVl\1U\10\254l\242\63)\0V\11\255t\262Ne\312\21W\12\255"
     "t\262J*\251.\0X\11\254l\242L*\312\0Y\12\255tr\252\63\312(\2Z\7\253df*"
-    "\7p\10\255\364V\266\323\2q\7\255\364\216\257\5r\10\253d\242\32*"
+    "\7p\10\255\364V\266\323\2q\7\255\364\216\257\5r\10\253d\242\32*\2t\6\255t\376#w\11"
-    "\2t\6\255t\376#w\11"
     "\255\364V\245FN\13x\6\233dR\7\0\0\0\4\377\377\0";
 
 /*
@@ -54,63 +47,42 @@ const uint8_t TEXT_FONT[437] U8G2_FONT_SECTION("velvetscreen") PROGMEM =
  * https://stncrn.github.io/u8g2-unifont-helper/
  * "%/0123456789ABCDEFILNORSTUVXx"
  */
-const uint8_t LARGE_FONT[766] U8G2_FONT_SECTION("stk-l") =
+const uint8_t LARGE_FONT[766] U8G2_FONT_SECTION("stk-l") PROGMEM =
     "\35\0\4\4\4\5\3\1\6\20\30\0\0\27\0\0\0\1\77\0\0\2\341%'\17;\226\261\245FL"
-    "\64B\214\30\22\223\220)"
+    "\64B\214\30\22\223\220)Bj\10Q\232\214\42R\206\310\210\21d\304\30\32a\254\304\270!\0/\14"
-    "Bj\10Q\232\214\42R\206\310\210\21d\304\30\32a\254\304\270!\0/\14"
+    "\272\272\275\311H\321g\343\306\1\60\37|\373\35CJT\20:fW\207\320\210\60\42\304\204\30D\247"
-    "\272\272\275\311H\321g\343\306\1\60\37|\373\35CJT\20:"
+    "\214\331\354\20\11%\212\314\0\61\24z\275\245a\244\12\231\71\63b\214\220q\363\377(E\6\62\33|"
-    "fW\207\320\210\60\42\304\204\30D\247"
+    "\373\35ShT\20:fl\344\14\211\231\301\306T\71\202#g\371\340\201\1\63\34|\373\35ShT"
-    "\214\331\354\20\11%"
+    "\20:fl\344@r\264\263\222\344,\215\35\42\241\6\225\31\0\64 |\373-!\203\206\214!\62\204"
-    "\212\314\0\61\24z\275\245a\244\12\231\71\63b\214\220q\363\377(E\6\62\33|"
+    "\314\220A#\10\215\30\65b\324\210Q\306\354\354\1\213\225\363\1\65\32|\373\15\25[\214\234/\10)"
-    "\373\35ShT\20:fl\344\14\211\231\301\306T\71\202#g\371\340\201\1\63\34|"
-    "\373\35ShT"
-    "\20:fl\344@r\264\263\222\344,\215\35\42\241\6\225\31\0\64 "
-    "|\373-!\203\206\214!\62\204"
-    "\314\220A#\10\215\30\65b\324\210Q\306\354\354\1\213\225\363\1\65\32|"
-    "\373\15\25[\214\234/\10)"
     "Y\61j\350\310Y\32;DB\15*\63\0\66\33}\33\236SiV\14;gt^\230Y\302\202\324"
-    "\71\273;EbM\252\63\0\67\23|\373\205\25\17R\316\207\344\350p\312\201#"
+    "\71\273;EbM\252\63\0\67\23|\373\205\25\17R\316\207\344\350p\312\201#\347\35\0\70 |\373"
-    "\347\35\0\70 |\373"
+    "\35ShT\20:f\331!\22D\310 :\205\206\10\11B\307\354\354\20\11\65\250\314\0\71\32|\373"
-    "\35ShT\20:f\331!\22D\310 "
-    ":\205\206\10\11B\307\354\354\20\11\65\250\314\0\71\32|\373"
     "\35ShT\20:fg\207H,Q\223r\276\30DB\15*\63\0A\26}\33\246r\247\322P\62"
-    "j\310\250\21\343\354\335\203\357\354w\3B$}"
+    "j\310\250\21\343\354\335\203\357\354w\3B$}\33\206Dj\226\214\42\61l\304\260\21\303F\14\33\61"
-    "\33\206Dj\226\214\42\61l\304\260\21\303F\14\33\61"
+    "\212\304\222MF\221\30v\316\236=\10\301b\11\0C\27}\33\236Si\226\20Bft\376O\211\215"
-    "\212\304\222MF\221\30v\316\236=\10\301b\11\0C\27}"
+    " Db\215\42$\0D\33}\33\206Dj\226\214\32\62l\304\260\21\343\354\177vl\304(\22K\324"
-    "\33\236Si\226\20Bft\376O\211\215"
+    "$\2E\22|\373\205\17R\316KD\30\215\234_>x`\0F\20|\373\205\17R\316\227i\262\31"
-    " Db\215\42$\0D\33}\33\206Dj\226\214\32\62l\304\260\21\343\354\177vl\304("
+    "\71\377\22\0I\7s\333\204\77HL\15{\333\205\201\363\377\77|\360`\0N$}\33\6\201\346\314"
-    "\22K\324"
+    "\35;\206\12U\242D&\306\230\30cd\210\221!fF\230\31a(+\314\256\63\67\0O\26}\33"
-    "$\2E\22|\373\205\17R\316KD\30\215\234_>x`\0F\20|"
+    "\236Si\226\214\32\61\316\376\277\33\61j\310\232Tg\0R\61\216;\6Ek\230\14#\61n\304\270"
-    "\373\205\17R\316\227i\262\31"
+    "\21\343F\214\33\61n\304\60\22\243\210\60Q\224j\310\260\61\243\306\20\232\325\230QD\206\221\30\67b"
-    "\71\377\22\0I\7s\333\204\77HL\15{\333\205\201\363\377\77|\360`\0N$}"
+    "\334\301\1S\42\216;\236c\211\226\220\42\61n\304\270\21c\307R\232,[\262\203\307\216\65h\16\25"
-    "\33\6\201\346\314"
+    "\21&\253\320\0T\15}\33\206\17R\15\235\377\377\25\0U\21|\373\205a\366\377\237\215\30\64D\15"
-    "\35;\206\12U\242D&\306\230\30cd\210\221!fF\230\31a(+\314\256\63\67\0O\26}"
+    "*\63\0V\26\177\371\205\221\366\377\313\21\343\206\220\42C\25\11r'\313\16\3X)~;\206\201\6"
-    "\33"
+    "\217\221\30\66\204\20\31\42\244\206\14Cg\320$Q\222\6\315!\33\62\212\10\31BD\206\215 v\320"
-    "\236Si\226\214\32\61\316\376\277\33\61j\310\232Tg\0R\61\216;\6Ek\230\14#"
+    "\302\1x\24\312\272\205A\206\216\220@c\212\224\31$S\14\262h\0\0\0\0\4\377\377\0";
-    "\61n\304\270"
-    "\21\343F\214\33\61n\304\60\22\243\210\60Q\224j\310\260\61\243\306\20\232"
-    "\325\230QD\206\221\30\67b"
-    "\334\301\1S\42\216;\236c\211\226\220\42\61n\304\270\21c\307R\232,["
-    "\262\203\307\216\65h\16\25"
-    "\21&\253\320\0T\15}\33\206\17R\15\235\377\377\25\0U\21|"
-    "\373\205a\366\377\237\215\30\64D\15"
-    "*\63\0V\26\177\371\205\221\366\377\313\21\343\206\220\42C\25\11r'"
-    "\313\16\3X)~;\206\201\6"
-    "\217\221\30\66\204\20\31\42\244\206\14Cg\320$Q\222\6\315!"
-    "\33\62\212\10\31BD\206\215 v\320"
-    "\302\1x\24\312\272\205A\206\216\220@c\212\224\31$"
-    "S\14\262h\0\0\0\0\4\377\377\0";
 
 #define play_icon_width 14
 #define play_icon_height 14
 static const unsigned char play_icon[28] PROGMEM = {
-    0x00, 0x00, 0x00, 0x00, 0x3C, 0x00, 0x7C, 0x00, 0xFC, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x3C, 0x00, 0x7C, 0x00, 0xFC, 0x00, 0xFC, 0x03,
-    0xFC, 0x03, 0xFC, 0x0F, 0xFC, 0x0F, 0xFC, 0x03, 0xFC, 0x00,
+    0xFC, 0x0F, 0xFC, 0x0F, 0xFC, 0x03, 0xFC, 0x00, 0x7C, 0x00, 0x3C, 0x00,
-    0x7C, 0x00, 0x3C, 0x00, 0x00, 0x00, 0x00, 0x00};
+    0x00, 0x00, 0x00, 0x00};
 static const unsigned char pause_icon[28] PROGMEM = {
-    0x00, 0x00, 0x00, 0x00, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E,
+    0x00, 0x00, 0x00, 0x00, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E,
-    0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E,
+    0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E,
-    0x38, 0x0E, 0x38, 0x0E, 0x38, 0x0E, 0x00, 0x00};
+    0x38, 0x0E, 0x00, 0x00};
 
 // Constants for screen layout and fonts
 constexpr uint8_t SCREEN_CENTER_X = 32;
@@ -132,10 +104,8 @@ enum ParamsMainPage : uint8_t {
     PARAM_MAIN_RESET,
     PARAM_MAIN_PULSE,
     PARAM_MAIN_ENCODER_DIR,
-  PARAM_MAIN_ROTATE_DISP,
     PARAM_MAIN_SAVE_DATA,
     PARAM_MAIN_LOAD_DATA,
-  PARAM_MAIN_RESET_STATE,
     PARAM_MAIN_FACTORY_RESET,
     PARAM_MAIN_LAST,
 };
@@ -147,20 +117,38 @@ enum ParamsChannelPage : uint8_t {
     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,
 };
 
+// Common/resused strings stored as const to save on flash memory.
+const char* const STR_24_PPQN = "24 PPQN";
+const char* const STR_4_PPQN = "4 PPQN";
+const char* const STR_1_PPQN = "1 PPQN";
+const char* const STR_CV_1 = "CV 1";
+const char* const STR_CV_2 = "CV 2";
+const char* const STR_NONE = "NONE";
+const char* const STR_EXT = "EXT";
+const char* const STR_X = "X";
+const char* const STR_DEFAULT = "DEFAULT";
+const char* const STR_REVERSED = "REVERSED";
+const char* const STR_FLIPPED = "FLIPPED";
+const char* const STR_BACK = "BACK TO MAIN";
+const char* const STR_EUC_STEPS = "EUCLID STEPS";
+const char* const STR_EUC_HITS = "EUCLID HITS";
+
 // Helper function to draw centered text
-void drawCenteredText(const char *text, int y, const uint8_t *font) {
+void drawCenteredText(const char* text, int y, const uint8_t* font) {
     gravity.display.setFont(font);
     int textWidth = gravity.display.getStrWidth(text);
     gravity.display.drawStr(SCREEN_CENTER_X - (textWidth / 2), y, text);
 }
 
 // Helper function to draw right-aligned text
-void drawRightAlignedText(const char *text, int y) {
+void drawRightAlignedText(const char* text, int y) {
     int textWidth = gravity.display.getStrWidth(text);
     int drawX = (SCREEN_WIDTH - textWidth) - MENU_BOX_PADDING;
     gravity.display.drawStr(drawX, y, text);
@@ -175,10 +163,8 @@ void drawMainSelection() {
     gravity.display.drawLine(0, 0, 0, tickSize);
     gravity.display.drawLine(mainWidth, 0, mainWidth - tickSize, 0);
     gravity.display.drawLine(mainWidth, 0, mainWidth, tickSize);
-  gravity.display.drawLine(mainWidth, mainHeight, mainWidth,
+    gravity.display.drawLine(mainWidth, mainHeight, mainWidth, mainHeight - tickSize);
-                           mainHeight - tickSize);
+    gravity.display.drawLine(mainWidth, mainHeight, mainWidth - tickSize, mainHeight);
-  gravity.display.drawLine(mainWidth, mainHeight, mainWidth - tickSize,
-                           mainHeight);
     gravity.display.drawLine(0, mainHeight, tickSize, mainHeight);
     gravity.display.drawLine(0, mainHeight, 0, mainHeight - tickSize);
     gravity.display.setDrawColor(2);
@@ -218,8 +204,7 @@ void drawMenuItems(String menu_items[], int menu_size) {
 
     for (int i = 0; i < min(menu_size, VISIBLE_MENU_ITEMS); ++i) {
         int idx = start_index + i;
-    drawRightAlignedText(menu_items[idx].c_str(),
+        drawRightAlignedText(menu_items[idx].c_str(), MENU_ITEM_HEIGHT * (i + 1) - 1);
-                         MENU_ITEM_HEIGHT * (i + 1) - 1);
     }
 }
 
@@ -229,7 +214,7 @@ inline void hollowTick() { gravity.display.drawBox(56, 4, 4, 4); }
 
 // Display an indicator when swing percentage matches a musical note.
 void swingDivisionMark() {
-  auto &ch = GetSelectedChannel();
+    auto& ch = GetSelectedChannel();
     switch (ch.getSwing()) {
         case 58:  // 1/32nd
         case 66:  // 1/16th
@@ -248,8 +233,7 @@ void swingDivisionMark() {
 String displaySaveSlot(int slot) {
     if (slot >= 0 && slot < StateManager::MAX_SAVE_SLOTS / 2) {
         return String("A") + String(slot + 1);
-  } else if (slot >= StateManager::MAX_SAVE_SLOTS / 2 &&
+    } else if (slot >= StateManager::MAX_SAVE_SLOTS / 2 && slot <= StateManager::MAX_SAVE_SLOTS) {
-             slot <= StateManager::MAX_SAVE_SLOTS) {
         return String("B") + String(slot - (StateManager::MAX_SAVE_SLOTS / 2) + 1);
     }
 }
@@ -269,30 +253,27 @@ void DisplayMainPage() {
         case PARAM_MAIN_TEMPO:
             // Serial MIDI is too unstable to display bpm in real time.
             if (app.selected_source == Clock::SOURCE_EXTERNAL_MIDI) {
-      mainText = F("EXT");
+                mainText = STR_EXT;
             } else {
                 mainText = String(gravity.clock.Tempo());
             }
             subText = F("BPM");
             break;
         case PARAM_MAIN_SOURCE:
-    mainText = F("EXT");
+            mainText = STR_EXT;
             switch (app.selected_source) {
                 case Clock::SOURCE_INTERNAL:
                     mainText = F("INT");
                     subText = F("CLOCK");
                     break;
                 case Clock::SOURCE_EXTERNAL_PPQN_24:
-      subText = F("24 PPQN");
+                    subText = STR_24_PPQN;
                     break;
                 case Clock::SOURCE_EXTERNAL_PPQN_4:
-      subText = F("4 PPQN");
+                    subText = STR_4_PPQN;
-      break;
-    case Clock::SOURCE_EXTERNAL_PPQN_2:
-      subText = F("2 PPQN");
                     break;
                 case Clock::SOURCE_EXTERNAL_PPQN_1:
-      subText = F("1 PPQN");
+                    subText = STR_1_PPQN;
                     break;
                 case Clock::SOURCE_EXTERNAL_MIDI:
                     subText = F("MIDI");
@@ -303,13 +284,13 @@ void DisplayMainPage() {
             mainText = F("RUN");
             switch (app.cv_run) {
                 case 0:
-      subText = F("NONE");
+                    subText = STR_NONE;
                     break;
                 case 1:
-      subText = F("CV 1");
+                    subText = STR_CV_1;
                     break;
                 case 2:
-      subText = F("CV 2");
+                    subText = STR_CV_2;
                     break;
             }
             break;
@@ -317,13 +298,13 @@ void DisplayMainPage() {
             mainText = F("RST");
             switch (app.cv_reset) {
                 case 0:
-      subText = F("NONE");
+                    subText = STR_NONE;
                     break;
                 case 1:
-      subText = F("CV 1");
+                    subText = STR_CV_1;
                     break;
                 case 2:
-      subText = F("CV 2");
+                    subText = STR_CV_2;
                     break;
             }
             break;
@@ -334,29 +315,25 @@ void DisplayMainPage() {
                     subText = F("PULSE OFF");
                     break;
                 case Clock::PULSE_PPQN_24:
-      subText = F("24 PPQN PULSE");
+                    subText = STR_24_PPQN;
                     break;
                 case Clock::PULSE_PPQN_4:
-      subText = F("4 PPQN PULSE");
+                    subText = STR_4_PPQN;
                     break;
                 case Clock::PULSE_PPQN_1:
-      subText = F("1 PPQN PULSE");
+                    subText = STR_1_PPQN;
                     break;
             }
             break;
         case PARAM_MAIN_ENCODER_DIR:
             mainText = F("DIR");
-    subText = app.selected_sub_param == 0 ? F("DEFAULT") : F("REVERSED");
+            subText = app.selected_sub_param == 0 ? STR_DEFAULT : STR_REVERSED;
-    break;
-  case PARAM_MAIN_ROTATE_DISP:
-    mainText = F("DISP");
-    subText = app.selected_sub_param == 0 ? F("DEFAULT") : F("ROTATED");
             break;
         case PARAM_MAIN_SAVE_DATA:
         case PARAM_MAIN_LOAD_DATA:
             if (app.selected_sub_param == StateManager::MAX_SAVE_SLOTS) {
-      mainText = F("x");
+                mainText = STR_X;
-      subText = F("BACK TO MAIN");
+                subText = STR_BACK;
             } else {
                 // Indicate currently active slot.
                 if (app.selected_sub_param == app.selected_save_slot) {
@@ -368,22 +345,13 @@ void DisplayMainPage() {
                               : F("LOAD FROM SLOT");
             }
             break;
-  case PARAM_MAIN_RESET_STATE:
-    if (app.selected_sub_param == 0) {
-      mainText = F("RST");
-      subText = F("RESET ALL");
-    } else {
-      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");
+                mainText = STR_X;
-      subText = F("BACK TO MAIN");
+                subText = STR_BACK;
             }
             break;
     }
@@ -392,15 +360,12 @@ void DisplayMainPage() {
     drawCenteredText(subText.c_str(), SUB_TEXT_Y, TEXT_FONT);
 
     // Draw Main Page menu items
-  String menu_items[PARAM_MAIN_LAST] = {
+    String menu_items[PARAM_MAIN_LAST] = {F("TEMPO"), F("SOURCE"), F("CLK RUN"), F("CLK RESET"), F("PULSE OUT"), F("ENCODER DIR"), F("SAVE"), F("LOAD"), F("ERASE")};
-      F("TEMPO"),     F("RUN"),         F("RST"),         F("SOURCE"),
-      F("PULSE OUT"), F("ENCODER DIR"), F("ROTATE DISP"), F("SAVE"),
-      F("LOAD"),      F("RESET"),       F("ERASE")};
     drawMenuItems(menu_items, PARAM_MAIN_LAST);
 }
 
 void DisplayChannelPage() {
-  auto &ch = GetSelectedChannel();
+    auto& ch = GetSelectedChannel();
 
     gravity.display.setFontMode(1);
     gravity.display.setDrawColor(2);
@@ -412,10 +377,12 @@ void DisplayChannelPage() {
     // When editing a param, just show the base value. When not editing show
     // the value with cv mod.
     bool withCvMod = !app.editing_param;
+    int cv1 = gravity.cv1.Read();
+    int cv2 = gravity.cv2.Read();
 
     switch (app.selected_param) {
         case PARAM_CH_MOD: {
-    int mod_value = ch.getClockMod(withCvMod);
+            int mod_value = withCvMod ? ch.getClockModWithMod(cv1, cv2): ch.getClockMod();
             if (mod_value > 1) {
                 mainText = F("/");
                 mainText += String(mod_value);
@@ -428,28 +395,36 @@ void DisplayChannelPage() {
             break;
         }
         case PARAM_CH_PROB:
-    mainText = String(ch.getProbability(withCvMod)) + F("%");
+            mainText = String(withCvMod ? ch.getProbabilityWithMod(cv1, cv2) : ch.getProbability()) + F("%");
             subText = F("HIT CHANCE");
             break;
         case PARAM_CH_DUTY:
-    mainText = String(ch.getDutyCycle(withCvMod)) + F("%");
+            mainText = String(withCvMod ? ch.getDutyCycleWithMod(cv1, cv2) : ch.getDutyCycle()) + F("%");
             subText = F("PULSE WIDTH");
             break;
         case PARAM_CH_OFFSET:
-    mainText = String(ch.getOffset(withCvMod)) + F("%");
+            mainText = String(withCvMod ? ch.getOffsetWithMod(cv1, cv2) : ch.getOffset()) + F("%");
             subText = F("SHIFT HIT");
             break;
         case PARAM_CH_SWING:
-    ch.getSwing() == 50 ? mainText = F("OFF")
+            ch.getSwing() == 50
-                        : mainText = String(ch.getSwing(withCvMod)) + F("%");
+                ? mainText = F("OFF")
-    subText = "DOWN BEAT";
+                : mainText = String(withCvMod ? ch.getSwingWithMod(cv1, cv2) : ch.getSwing()) + F("%");
+            subText = F("DOWN BEAT");
             swingDivisionMark();
             break;
+        case PARAM_CH_EUC_STEPS:
+            mainText = String(withCvMod ? ch.getStepsWithMod(cv1, cv2) : ch.getSteps());
+            subText = STR_EUC_STEPS;
+            break;
+        case PARAM_CH_EUC_HITS:
+            mainText = String(withCvMod ? ch.getHitsWithMod(cv1, cv2) : ch.getHits());
+            subText = STR_EUC_HITS;
+            break;
         case PARAM_CH_CV1_DEST:
         case PARAM_CH_CV2_DEST: {
             mainText = (app.selected_param == PARAM_CH_CV1_DEST) ? F("CV1") : F("CV2");
-    switch ((app.selected_param == PARAM_CH_CV1_DEST) ? ch.getCv1Dest()
+            switch ((app.selected_param == PARAM_CH_CV1_DEST) ? ch.getCv1Dest() : ch.getCv2Dest()) {
-                                                      : ch.getCv2Dest()) {
                 case CV_DEST_NONE:
                     subText = F("NONE");
                     break;
@@ -468,6 +443,12 @@ void DisplayChannelPage() {
                 case CV_DEST_SWING:
                     subText = F("SWING");
                     break;
+                case CV_DEST_EUC_STEPS:
+                    subText = STR_EUC_STEPS;
+                    break;
+                case CV_DEST_EUC_HITS:
+                    subText = STR_EUC_HITS;
+                    break;
             }
             break;
         }
@@ -478,8 +459,8 @@ void DisplayChannelPage() {
 
     // Draw Channel Page menu items
     String menu_items[PARAM_CH_LAST] = {
-      F("MOD"),   F("PROBABILITY"), F("DUTY"),   F("OFFSET"),
+        F("MOD"), F("PROBABILITY"), F("DUTY"), F("OFFSET"), F("SWING"), F("EUCLID STEPS"),
-      F("SWING"), F("CV1 MOD"),     F("CV2 MOD")};
+        F("EUCLID HITS"), F("CV1 MOD"), F("CV2 MOD")};
     drawMenuItems(menu_items, PARAM_CH_LAST);
 }
 
@@ -506,8 +487,7 @@ void DisplaySelectedChannel() {
         if (i == 0) {
             gravity.display.setBitmapMode(1);
             auto icon = gravity.clock.IsPaused() ? pause_icon : play_icon;
-      gravity.display.drawXBMP(2, boxY, play_icon_width, play_icon_height,
+            gravity.display.drawXBMP(2, boxY, play_icon_width, play_icon_height, icon);
-                               icon);
         } else {
             gravity.display.setFont(TEXT_FONT);
             gravity.display.setCursor((i * boxWidth) + textOffset, SCREEN_HEIGHT - 3);
@@ -538,12 +518,10 @@ void Bootsplash() {
         gravity.display.setFont(TEXT_FONT);
 
         textWidth = gravity.display.getStrWidth(StateManager::SKETCH_NAME);
-    gravity.display.drawStr(16 + (textWidth / 2), 20,
+        gravity.display.drawStr(16 + (textWidth / 2), 20, StateManager::SKETCH_NAME);
-                            StateManager::SKETCH_NAME);
 
         textWidth = gravity.display.getStrWidth(StateManager::SEMANTIC_VERSION);
-    gravity.display.drawStr(16 + (textWidth / 2), 32,
+        gravity.display.drawStr(16 + (textWidth / 2), 32, StateManager::SEMANTIC_VERSION);
-                            StateManager::SEMANTIC_VERSION);
 
         textWidth = gravity.display.getStrWidth(loadingText.c_str());
         gravity.display.drawStr(26 + (textWidth / 2), 44, loadingText.c_str());

firmware/Gravity/save_state.cpp

@@ -17,9 +17,7 @@
 
 // Define the constants for the current firmware.
 const char StateManager::SKETCH_NAME[] = "ALT GRAVITY";
-const char StateManager::SEMANTIC_VERSION[] =
+const char StateManager::SEMANTIC_VERSION[] = "V2.0.0BETA4";  // NOTE: This should match the version in the library.properties file.
-    "V2.0.1BETA1"; // NOTE: This should match the version in the
-                   // library.properties file.
 
 // Number of available save slots.
 const byte StateManager::MAX_SAVE_SLOTS = 10;
@@ -34,74 +32,55 @@ const int StateManager::EEPROM_DATA_START_ADDR = sizeof(StateManager::Metadata);
 
 StateManager::StateManager() : _isDirty(false), _lastChangeTime(0) {}
 
-bool StateManager::initialize(AppState &app) {
+bool StateManager::initialize(AppState& app) {
-  noInterrupts();
-  bool success = false;
     if (_isDataValid()) {
         // Load global settings.
         _loadMetadata(app);
         // Load app data from the transient slot.
         _loadState(app, TRANSIENT_SLOT);
-    success = true;
+        return true;
     }
     // EEPROM does not contain save data for this firmware & version.
     else {
-    // Erase EEPROM and initialize state. Save default pattern to all save
+        // Erase EEPROM and initialize state. Save default pattern to all save slots.
-    // slots.
         factoryReset(app);
+        return false;
     }
-  interrupts();
-  return success;
 }
 
-bool StateManager::loadData(AppState &app, byte slot_index) {
+bool StateManager::loadData(AppState& app, byte slot_index) {
     // Check if slot_index is within max range + 1 for transient.
-  if (slot_index >= MAX_SAVE_SLOTS + 1)
+    if (slot_index >= MAX_SAVE_SLOTS + 1) return false;
-    return false;
 
-  noInterrupts();
+    // Load the state data from the specified EEPROM slot and update the app state save slot.
-
-  // 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 on next update.
+    // Persist this change in the global metadata.
-  _isDirty = true;
+    _saveMetadata(app);
 
-  interrupts();
     return true;
 }
 
 // Save app state to user specified save slot.
-void StateManager::saveData(const AppState &app) {
+void StateManager::saveData(const AppState& app) {
-  noInterrupts();
     // Check if slot_index is within max range + 1 for transient.
-  if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1) {
+    if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1) return;
-    interrupts();
-    return;
-  }
 
     _saveState(app, app.selected_save_slot);
     _saveMetadata(app);
     _isDirty = false;
-  interrupts();
 }
 
-// Save transient state if it has changed and enough time has passed since last
+// Save transient state if it has changed and enough time has passed since last save.
-// save.
+void StateManager::update(const AppState& app) {
-void StateManager::update(const AppState &app) {
     if (_isDirty && (millis() - _lastChangeTime > SAVE_DELAY_MS)) {
-    noInterrupts();
         _saveState(app, TRANSIENT_SLOT);
         _saveMetadata(app);
         _isDirty = false;
-    interrupts();
     }
 }
 
-void StateManager::reset(AppState &app) {
+void StateManager::reset(AppState& app) {
-  noInterrupts();
-
     AppState default_app;
     app.tempo = default_app.tempo;
     app.selected_param = default_app.selected_param;
@@ -119,7 +98,6 @@ void StateManager::reset(AppState &app) {
     _loadMetadata(app);
 
     _isDirty = false;
-  interrupts();
 }
 
 void StateManager::markDirty() {
@@ -128,7 +106,7 @@ void StateManager::markDirty() {
 }
 
 // Erases all data in the EEPROM by writing 0 to every address.
-void StateManager::factoryReset(AppState &app) {
+void StateManager::factoryReset(AppState& app) {
     noInterrupts();
     for (unsigned int i = 0; i < EEPROM.length(); i++) {
         EEPROM.write(i, 0);
@@ -152,11 +130,11 @@ bool StateManager::_isDataValid() {
     return name_match && version_match;
 }
 
-void StateManager::_saveState(const AppState &app, byte slot_index) {
+void StateManager::_saveState(const AppState& app, byte slot_index) {
     // Check if slot_index is within max range + 1 for transient.
-  if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1)
+    if (app.selected_save_slot >= MAX_SAVE_SLOTS + 1) return;
-    return;
 
+    noInterrupts();
     static EepromData save_data;
 
     save_data.tempo = app.tempo;
@@ -172,25 +150,29 @@ void StateManager::_saveState(const AppState &app, byte slot_index) {
     // "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];
+        const auto& ch = app.channel[i];
-    auto &save_ch = save_data.channel_data[i];
+        auto& save_ch = save_data.channel_data[i];
-    save_ch.base_clock_mod_index = ch.getClockModIndex(false);
+        save_ch.base_clock_mod_index = ch.getClockModIndex();
-    save_ch.base_probability = ch.getProbability(false);
+        save_ch.base_probability = ch.getProbability();
-    save_ch.base_duty_cycle = ch.getDutyCycle(false);
+        save_ch.base_duty_cycle = ch.getDutyCycle();
-    save_ch.base_offset = ch.getOffset(false);
+        save_ch.base_offset = ch.getOffset();
+        save_ch.base_swing = ch.getSwing();
+        save_ch.base_euc_steps = ch.getSteps();
+        save_ch.base_euc_hits = ch.getHits();
         save_ch.cv1_dest = static_cast<byte>(ch.getCv1Dest());
         save_ch.cv2_dest = static_cast<byte>(ch.getCv2Dest());
     }
 
     int address = EEPROM_DATA_START_ADDR + (slot_index * sizeof(EepromData));
     EEPROM.put(address, save_data);
+    interrupts();
 }
 
-void StateManager::_loadState(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)
+    if (slot_index >= MAX_SAVE_SLOTS + 1) return;
-    return;
 
+    noInterrupts();
     static EepromData load_data;
     int address = EEPROM_DATA_START_ADDR + (slot_index * sizeof(EepromData));
     EEPROM.get(address, load_data);
@@ -205,19 +187,24 @@ void StateManager::_loadState(AppState &app, byte slot_index) {
     app.cv_reset = load_data.cv_reset;
 
     for (int i = 0; i < Gravity::OUTPUT_COUNT; i++) {
-    auto &ch = app.channel[i];
+        auto& ch = app.channel[i];
-    const auto &saved_ch_state = load_data.channel_data[i];
+        const auto& saved_ch_state = load_data.channel_data[i];
 
         ch.setClockMod(saved_ch_state.base_clock_mod_index);
         ch.setProbability(saved_ch_state.base_probability);
         ch.setDutyCycle(saved_ch_state.base_duty_cycle);
         ch.setOffset(saved_ch_state.base_offset);
+        ch.setSwing(saved_ch_state.base_swing);
+        ch.setSteps(saved_ch_state.base_euc_steps);
+        ch.setHits(saved_ch_state.base_euc_hits);
         ch.setCv1Dest(static_cast<CvDestination>(saved_ch_state.cv1_dest));
         ch.setCv2Dest(static_cast<CvDestination>(saved_ch_state.cv2_dest));
     }
+    interrupts();
 }
 
-void StateManager::_saveMetadata(const AppState &app) {
+void StateManager::_saveMetadata(const AppState& app) {
+    noInterrupts();
     Metadata current_meta;
     strcpy(current_meta.sketch_name, SKETCH_NAME);
     strcpy(current_meta.version, SEMANTIC_VERSION);
@@ -225,15 +212,16 @@ void StateManager::_saveMetadata(const AppState &app) {
     // Global user settings
     current_meta.selected_save_slot = app.selected_save_slot;
     current_meta.encoder_reversed = app.encoder_reversed;
-  current_meta.rotate_display = app.rotate_display;
 
     EEPROM.put(METADATA_START_ADDR, current_meta);
+    interrupts();
 }
 
-void StateManager::_loadMetadata(AppState &app) {
+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;
-  app.rotate_display = metadata.rotate_display;
+    interrupts();
 }

firmware/Gravity/save_state.h

@@ -19,15 +19,15 @@
 struct AppState;
 
 /**
- * @brief Manages saving and loading of the application state to and from
+ * @brief Manages saving and loading of the application state to and from EEPROM.
- * EEPROM. The number of user slots is defined by MAX_SAVE_SLOTS, and one
+ * The number of user slots is defined by MAX_SAVE_SLOTS, and one additional slot
- * additional slot is reseved for transient state to persist state between power
+ * is reseved for transient state to persist state between power cycles before
- * cycles before state is explicitly saved to a user slot. Metadata is stored in
+ * state is explicitly saved to a user slot. Metadata is stored in the beginning
- * the beginning of the memory space which stores firmware version information
+ * of the memory space which stores firmware version information to validate that
- * to validate that the data can be loaded into the current version of AppState.
+ * the data can be loaded into the current version of AppState.
  */
 class StateManager {
-public:
+   public:
     static const char SKETCH_NAME[];
     static const char SEMANTIC_VERSION[];
     static const byte MAX_SAVE_SLOTS;
@@ -36,19 +36,19 @@ public:
     StateManager();
 
     // Populate the AppState instance with values from EEPROM if they exist.
-  bool initialize(AppState &app);
+    bool initialize(AppState& app);
     // Load data from specified slot.
-  bool loadData(AppState &app, byte slot_index);
+    bool loadData(AppState& app, byte slot_index);
     // Save data to specified slot.
-  void saveData(const AppState &app);
+    void saveData(const AppState& app);
     // Reset AppState instance back to default values.
-  void reset(AppState &app);
+    void reset(AppState& app);
     // Call from main loop, check if state has changed and needs to be saved.
-  void update(const AppState &app);
+    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);
+    void factoryReset(AppState& app);
 
     // This struct holds the data that identifies the firmware version.
     struct Metadata {
@@ -57,13 +57,15 @@ public:
         // Additional global/hardware settings
         byte selected_save_slot;
         bool encoder_reversed;
-    bool rotate_display;
     };
     struct ChannelState {
         byte base_clock_mod_index;
         byte base_probability;
         byte base_duty_cycle;
         byte base_offset;
+        byte base_swing;
+        byte base_euc_steps;
+        byte base_euc_hits;
         byte cv1_dest;  // Cast the CvDestination enum as a byte for storage
         byte cv2_dest;  // Cast the CvDestination enum as a byte for storage
     };
@@ -79,12 +81,12 @@ public:
         ChannelState channel_data[Gravity::OUTPUT_COUNT];
     };
 
-private:
+   private:
     bool _isDataValid();
-  void _saveMetadata(const AppState &app);
+    void _saveMetadata(const AppState& app);
-  void _loadMetadata(AppState &app);
+    void _loadMetadata(AppState& app);
-  void _saveState(const AppState &app, byte slot_index);
+    void _saveState(const AppState& app, byte slot_index);
-  void _loadState(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;

library.properties

@@ -1,4 +1,5 @@
-version=2.0.1beta1
+name=libGravity
+version=2.0.0beta3
 author=Adam Wonak
 maintainer=awonak <github.com/awonak>
 sentence=Hardware abstraction library for Sitka Instruments Gravity eurorack module

src/analog_input.h

@@ -18,7 +18,7 @@ const int CALIBRATED_LOW = -566;
 const int CALIBRATED_HIGH = 512;
 
 class AnalogInput {
-public:
+   public:
     static const int GATE_THRESHOLD = 0;
 
     AnalogInput() {}
@@ -43,8 +43,7 @@ public:
         int raw = analogRead(pin_);
         read_ = map(raw, 0, MAX_INPUT, low_, high_);
         read_ = constrain(read_ - offset_, -512, 512);
-    if (inverted_)
+        if (inverted_) read_ = -read_;
-      read_ = -read_;
     }
 
     // Set calibration values.
@@ -53,7 +52,7 @@ public:
 
     void AdjustCalibrationHigh(int amount) { high_ += amount; }
 
-  void SetOffset(float percent) { offset_ = -(percent) * 512; }
+    void SetOffset(float percent) { offset_ = -(percent)*512; }
 
     void SetAttenuation(float percent) {
         low_ = abs(percent) * CALIBRATED_LOW;
@@ -81,8 +80,7 @@ public:
      * Checks for a rising edge transition across a threshold.
      *
      * @param threshold The value that the input must cross.
-   * @return True if the value just crossed the threshold from below, false
+     * @return True if the value just crossed the threshold from below, false otherwise.
-   * otherwise.
      */
     inline bool IsRisingEdge(int16_t threshold) const {
         bool was_high = old_read_ > threshold;
@@ -90,7 +88,7 @@ public:
         return is_high && !was_high;
     }
 
-private:
+   private:
     uint8_t pin_;
     int16_t read_;
     uint16_t old_read_;

src/clock.h

@@ -17,8 +17,7 @@
 #include "peripherials.h"
 #include "uClock/uClock.h"
 
-// MIDI clock, start, stop, and continue byte definitions - based on MIDI 1.0
+// MIDI clock, start, stop, and continue byte definitions - based on MIDI 1.0 Standards.
-// Standards.
 #define MIDI_CLOCK 0xF8
 #define MIDI_START 0xFA
 #define MIDI_STOP 0xFC
@@ -29,7 +28,7 @@ static ExtCallback extUserCallback = nullptr;
 static void serialEventNoop(uint8_t msg, uint8_t status) {}
 
 class Clock {
-public:
+   public:
     static constexpr int DEFAULT_TEMPO = 120;
 
     enum Source {
@@ -67,8 +66,7 @@ public:
         uClock.start();
     }
 
-  // Handle external clock tick and call user callback when receiving clock
+    // Handle external clock tick and call user callback when receiving clock trigger (PPQN_4, PPQN_24, or MIDI).
-  // trigger (PPQN_4, PPQN_24, or MIDI).
     void AttachExtHandler(void (*callback)()) {
         extUserCallback = callback;
         attachInterrupt(digitalPinToInterrupt(EXT_PIN), callback, RISING);
@@ -83,8 +81,7 @@ public:
     void SetSource(Source source) {
         bool was_playing = !IsPaused();
         uClock.stop();
-    // If we are changing the source from MIDI, disable the serial interrupt
+        // If we are changing the source from MIDI, disable the serial interrupt handler.
-    // handler.
         if (source_ == SOURCE_EXTERNAL_MIDI) {
             NeoSerial.attachInterrupt(serialEventNoop);
         }
@@ -120,8 +117,7 @@ public:
         }
     }
 
-  // Return true if the current selected source is externl (PPQN_4, PPQN_24, or
+    // Return true if the current selected source is externl (PPQN_4, PPQN_24, or MIDI).
-  // MIDI).
     bool ExternalSource() {
         return uClock.getClockMode() == uClock.EXTERNAL_CLOCK;
     }
@@ -132,28 +128,41 @@ public:
     }
 
     // Returns the current BPM tempo.
-  int Tempo() { return uClock.getTempo(); }
+    int Tempo() {
+        return uClock.getTempo();
+    }
 
     // Set the clock tempo to a int between 1 and 400.
-  void SetTempo(int tempo) { return uClock.setTempo(tempo); }
+    void SetTempo(int tempo) {
+        return uClock.setTempo(tempo);
+    }
 
-  // Record an external clock tick received to process external/internal
+    // Record an external clock tick received to process external/internal syncronization.
-  // syncronization.
+    void Tick() {
-  void Tick() { uClock.clockMe(); }
+        uClock.clockMe();
+    }
 
     // Start the internal clock.
-  void Start() { uClock.start(); }
+    void Start() {
+        uClock.start();
+    }
 
     // Stop internal clock clock.
-  void Stop() { uClock.stop(); }
+    void Stop() {
+        uClock.stop();
+    }
 
     // Reset all clock counters to 0.
-  void Reset() { uClock.resetCounters(); }
+    void Reset() {
+        uClock.resetCounters();
+    }
 
     // Returns true if the clock is not running.
-  bool IsPaused() { return uClock.clock_state == uClock.PAUSED; }
+    bool IsPaused() {
+        return uClock.clock_state == uClock.PAUSED;
+    }
 
-private:
+   private:
     Source source_ = SOURCE_INTERNAL;
 
     static void onSerialEvent(uint8_t msg, uint8_t status) {
@@ -176,11 +185,17 @@ private:
         }
     }
 
-  static void sendMIDIStart() { NeoSerial.write(MIDI_START); }
+    static void sendMIDIStart() {
+        NeoSerial.write(MIDI_START);
+    }
 
-  static void sendMIDIStop() { NeoSerial.write(MIDI_STOP); }
+    static void sendMIDIStop() {
+        NeoSerial.write(MIDI_STOP);
+    }
 
-  static void sendMIDIClock(uint32_t tick) { NeoSerial.write(MIDI_CLOCK); }
+    static void sendMIDIClock(uint32_t tick) {
+        NeoSerial.write(MIDI_CLOCK);
+    }
 };
 
 #endif

src/digital_output.h

@@ -16,7 +16,7 @@
 const byte DEFAULT_TRIGGER_DURATION_MS = 5;
 
 class DigitalOutput {
-public:
+   public:
     /**
      * Initializes an CV Output paired object.
      *
@@ -43,10 +43,8 @@ public:
      * @param state Arduino digital HIGH or LOW values.
      */
     inline void Update(uint8_t state) {
-    if (state == HIGH)
+        if (state == HIGH) High();  // Rising
-      High(); // Rising
+        if (state == LOW) Low();    // Falling
-    if (state == LOW)
-      Low(); // Falling
     }
 
     // Sets the cv output HIGH to about 5v.
@@ -67,8 +65,7 @@ public:
      * Return a bool representing the on/off state of the output.
      */
     inline void Process() {
-    // If trigger is HIGH and the trigger duration time has elapsed, set the
+        // If trigger is HIGH and the trigger duration time has elapsed, set the output low.
-    // output low.
         if (on_ && (millis() - last_triggered_) >= trigger_duration_) {
             update(LOW);
         }
@@ -81,7 +78,7 @@ public:
      */
     inline bool On() { return on_; }
 
-private:
+   private:
     unsigned long last_triggered_;
     uint8_t trigger_duration_;
     uint8_t cv_pin_;