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Diffstat (limited to 'quantum/audio/audio.c')
| -rw-r--r-- | quantum/audio/audio.c | 539 |
1 files changed, 539 insertions, 0 deletions
diff --git a/quantum/audio/audio.c b/quantum/audio/audio.c new file mode 100644 index 0000000000..46277dd70b --- /dev/null +++ b/quantum/audio/audio.c @@ -0,0 +1,539 @@ +/* Copyright 2016-2020 Jack Humbert + * Copyright 2020 JohSchneider + + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include "audio.h" +#include "eeconfig.h" +#include "timer.h" +#include "wait.h" + +/* audio system: + * + * audio.[ch] takes care of all overall state, tracking the actively playing + * notes/tones; the notes a SONG consists of; + * ... + * = everything audio-related that is platform agnostic + * + * driver_[avr|chibios]_[dac|pwm] take care of the lower hardware dependent parts, + * specific to each platform and the used subsystem/driver to drive + * the output pins/channels with the calculated frequencies for each + * active tone + * as part of this, the driver has to trigger regular state updates by + * calling 'audio_update_state' through some sort of timer - be it a + * dedicated one or piggybacking on for example the timer used to + * generate a pwm signal/clock. + * + * + * A Note on terminology: + * tone, pitch and frequency are used somewhat interchangeably, in a strict Wikipedia-sense: + * "(Musical) tone, a sound characterized by its duration, pitch (=frequency), + * intensity (=volume), and timbre" + * - intensity/volume is currently not handled at all, although the 'dac_additive' driver could do so + * - timbre is handled globally (TODO: only used with the pwm drivers at the moment) + * + * in musical_note.h a 'note' is the combination of a pitch and a duration + * these are used to create SONG arrays; during playback their frequencies + * are handled as single successive tones, while the durations are + * kept track of in 'audio_update_state' + * + * 'voice' as it is used here, equates to a sort of instrument with its own + * characteristics sound and effects + * the audio system as-is deals only with (possibly multiple) tones of one + * instrument/voice at a time (think: chords). since the number of tones that + * can be reproduced depends on the hardware/driver in use: pwm can only + * reproduce one tone per output/speaker; DACs can reproduce/mix multiple + * when doing additive synthesis. + * + * 'duration' can either be in the beats-per-minute related unit found in + * musical_notes.h, OR in ms; keyboards create SONGs with the former, while + * the internal state of the audio system does its calculations with the later - ms + */ + +#ifndef AUDIO_TONE_STACKSIZE +# define AUDIO_TONE_STACKSIZE 8 +#endif +uint8_t active_tones = 0; // number of tones pushed onto the stack by audio_play_tone - might be more than the hardware is able to reproduce at any single time +musical_tone_t tones[AUDIO_TONE_STACKSIZE]; // stack of currently active tones + +bool playing_melody = false; // playing a SONG? +bool playing_note = false; // or (possibly multiple simultaneous) tones +bool state_changed = false; // global flag, which is set if anything changes with the active_tones + +// melody/SONG related state variables +float (*notes_pointer)[][2]; // SONG, an array of MUSICAL_NOTEs +uint16_t notes_count; // length of the notes_pointer array +bool notes_repeat; // PLAY_SONG or PLAY_LOOP? +uint16_t melody_current_note_duration = 0; // duration of the currently playing note from the active melody, in ms +uint8_t note_tempo = TEMPO_DEFAULT; // beats-per-minute +uint16_t current_note = 0; // index into the array at notes_pointer +bool note_resting = false; // if a short pause was introduced between two notes with the same frequency while playing a melody +uint16_t last_timestamp = 0; + +#ifdef AUDIO_ENABLE_TONE_MULTIPLEXING +# ifndef AUDIO_MAX_SIMULTANEOUS_TONES +# define AUDIO_MAX_SIMULTANEOUS_TONES 3 +# endif +uint16_t tone_multiplexing_rate = AUDIO_TONE_MULTIPLEXING_RATE_DEFAULT; +uint8_t tone_multiplexing_index_shift = 0; // offset used on active-tone array access +#endif + +// provided and used by voices.c +extern uint8_t note_timbre; +extern bool glissando; +extern bool vibrato; +extern uint16_t voices_timer; + +#ifndef STARTUP_SONG +# define STARTUP_SONG SONG(STARTUP_SOUND) +#endif +#ifndef AUDIO_ON_SONG +# define AUDIO_ON_SONG SONG(AUDIO_ON_SOUND) +#endif +#ifndef AUDIO_OFF_SONG +# define AUDIO_OFF_SONG SONG(AUDIO_OFF_SOUND) +#endif +float startup_song[][2] = STARTUP_SONG; +float audio_on_song[][2] = AUDIO_ON_SONG; +float audio_off_song[][2] = AUDIO_OFF_SONG; + +static bool audio_initialized = false; +static bool audio_driver_stopped = true; +audio_config_t audio_config; + +void audio_init() { + if (audio_initialized) { + return; + } + + // Check EEPROM +#ifdef EEPROM_ENABLE + if (!eeconfig_is_enabled()) { + eeconfig_init(); + } + audio_config.raw = eeconfig_read_audio(); +#else // EEPROM settings + audio_config.enable = true; +# ifdef AUDIO_CLICKY_ON + audio_config.clicky_enable = true; +# endif +#endif // EEPROM settings + + for (uint8_t i = 0; i < AUDIO_TONE_STACKSIZE; i++) { + tones[i] = (musical_tone_t){.time_started = 0, .pitch = -1.0f, .duration = 0}; + } + + if (!audio_initialized) { + audio_driver_initialize(); + audio_initialized = true; + } + stop_all_notes(); +} + +void audio_startup(void) { + if (audio_config.enable) { + PLAY_SONG(startup_song); + } + + last_timestamp = timer_read(); +} + +void audio_toggle(void) { + if (audio_config.enable) { + stop_all_notes(); + } + audio_config.enable ^= 1; + eeconfig_update_audio(audio_config.raw); + if (audio_config.enable) { + audio_on_user(); + } +} + +void audio_on(void) { + audio_config.enable = 1; + eeconfig_update_audio(audio_config.raw); + audio_on_user(); + PLAY_SONG(audio_on_song); +} + +void audio_off(void) { + PLAY_SONG(audio_off_song); + wait_ms(100); + audio_stop_all(); + audio_config.enable = 0; + eeconfig_update_audio(audio_config.raw); +} + +bool audio_is_on(void) { return (audio_config.enable != 0); } + +void audio_stop_all() { + if (audio_driver_stopped) { + return; + } + + active_tones = 0; + + audio_driver_stop(); + + playing_melody = false; + playing_note = false; + + melody_current_note_duration = 0; + + for (uint8_t i = 0; i < AUDIO_TONE_STACKSIZE; i++) { + tones[i] = (musical_tone_t){.time_started = 0, .pitch = -1.0f, .duration = 0}; + } + + audio_driver_stopped = true; +} + +void audio_stop_tone(float pitch) { + if (pitch < 0.0f) { + pitch = -1 * pitch; + } + + if (playing_note) { + if (!audio_initialized) { + audio_init(); + } + bool found = false; + for (int i = AUDIO_TONE_STACKSIZE - 1; i >= 0; i--) { + found = (tones[i].pitch == pitch); + if (found) { + tones[i] = (musical_tone_t){.time_started = 0, .pitch = -1.0f, .duration = 0}; + for (int j = i; (j < AUDIO_TONE_STACKSIZE - 1); j++) { + tones[j] = tones[j + 1]; + tones[j + 1] = (musical_tone_t){.time_started = 0, .pitch = -1.0f, .duration = 0}; + } + break; + } + } + if (!found) { + return; + } + + state_changed = true; + active_tones--; + if (active_tones < 0) active_tones = 0; +#ifdef AUDIO_ENABLE_TONE_MULTIPLEXING + if (tone_multiplexing_index_shift >= active_tones) { + tone_multiplexing_index_shift = 0; + } +#endif + if (active_tones == 0) { + audio_driver_stop(); + audio_driver_stopped = true; + playing_note = false; + } + } +} + +void audio_play_note(float pitch, uint16_t duration) { + if (!audio_config.enable) { + return; + } + + if (!audio_initialized) { + audio_init(); + } + + if (pitch < 0.0f) { + pitch = -1 * pitch; + } + + // round-robin: shifting out old tones, keeping only unique ones + // if the new frequency is already amongst the active tones, shift it to the top of the stack + bool found = false; + for (int i = active_tones - 1; i >= 0; i--) { + found = (tones[i].pitch == pitch); + if (found) { + for (int j = i; (j < active_tones - 1); j++) { + tones[j] = tones[j + 1]; + tones[j + 1] = (musical_tone_t){.time_started = timer_read(), .pitch = pitch, .duration = duration}; + } + return; // since this frequency played already, the hardware was already started + } + } + + // frequency/tone is actually new, so we put it on the top of the stack + active_tones++; + if (active_tones > AUDIO_TONE_STACKSIZE) { + active_tones = AUDIO_TONE_STACKSIZE; + // shift out the oldest tone to make room + for (int i = 0; i < active_tones - 1; i++) { + tones[i] = tones[i + 1]; + } + } + state_changed = true; + playing_note = true; + tones[active_tones - 1] = (musical_tone_t){.time_started = timer_read(), .pitch = pitch, .duration = duration}; + + // TODO: needs to be handled per note/tone -> use its timestamp instead? + voices_timer = timer_read(); // reset to zero, for the effects added by voices.c + + if (audio_driver_stopped) { + audio_driver_start(); + audio_driver_stopped = false; + } +} + +void audio_play_tone(float pitch) { audio_play_note(pitch, 0xffff); } + +void audio_play_melody(float (*np)[][2], uint16_t n_count, bool n_repeat) { + if (!audio_config.enable) { + audio_stop_all(); + return; + } + + if (!audio_initialized) { + audio_init(); + } + + // Cancel note if a note is playing + if (playing_note) audio_stop_all(); + + playing_melody = true; + note_resting = false; + + notes_pointer = np; + notes_count = n_count; + notes_repeat = n_repeat; + + current_note = 0; // note in the melody-array/list at note_pointer + + // start first note manually, which also starts the audio_driver + // all following/remaining notes are played by 'audio_update_state' + audio_play_note((*notes_pointer)[current_note][0], audio_duration_to_ms((*notes_pointer)[current_note][1])); + last_timestamp = timer_read(); + melody_current_note_duration = audio_duration_to_ms((*notes_pointer)[current_note][1]); +} + +float click[2][2]; +void audio_play_click(uint16_t delay, float pitch, uint16_t duration) { + uint16_t duration_tone = audio_ms_to_duration(duration); + uint16_t duration_delay = audio_ms_to_duration(delay); + + if (delay <= 0.0f) { + click[0][0] = pitch; + click[0][1] = duration_tone; + click[1][0] = 0.0f; + click[1][1] = 0.0f; + audio_play_melody(&click, 1, false); + } else { + // first note is a rest/pause + click[0][0] = 0.0f; + click[0][1] = duration_delay; + // second note is the actual click + click[1][0] = pitch; + click[1][1] = duration_tone; + audio_play_melody(&click, 2, false); + } +} + +bool audio_is_playing_note(void) { return playing_note; } + +bool audio_is_playing_melody(void) { return playing_melody; } + +uint8_t audio_get_number_of_active_tones(void) { return active_tones; } + +float audio_get_frequency(uint8_t tone_index) { + if (tone_index >= active_tones) { + return 0.0f; + } + return tones[active_tones - tone_index - 1].pitch; +} + +float audio_get_processed_frequency(uint8_t tone_index) { + if (tone_index >= active_tones) { + return 0.0f; + } + + int8_t index = active_tones - tone_index - 1; + // new tones are stacked on top (= appended at the end), so the most recent/current is MAX-1 + +#ifdef AUDIO_ENABLE_TONE_MULTIPLEXING + index = index - tone_multiplexing_index_shift; + if (index < 0) // wrap around + index += active_tones; +#endif + + if (tones[index].pitch <= 0.0f) { + return 0.0f; + } + + return voice_envelope(tones[index].pitch); +} + +bool audio_update_state(void) { + if (!playing_note && !playing_melody) { + return false; + } + + bool goto_next_note = false; + uint16_t current_time = timer_read(); + + if (playing_melody) { + goto_next_note = timer_elapsed(last_timestamp) >= melody_current_note_duration; + if (goto_next_note) { + uint16_t delta = timer_elapsed(last_timestamp) - melody_current_note_duration; + last_timestamp = current_time; + uint16_t previous_note = current_note; + current_note++; + voices_timer = timer_read(); // reset to zero, for the effects added by voices.c + + if (current_note >= notes_count) { + if (notes_repeat) { + current_note = 0; + } else { + audio_stop_all(); + return false; + } + } + + if (!note_resting && (*notes_pointer)[previous_note][0] == (*notes_pointer)[current_note][0]) { + note_resting = true; + + // special handling for successive notes of the same frequency: + // insert a short pause to separate them audibly + audio_play_note(0.0f, audio_duration_to_ms(2)); + current_note = previous_note; + melody_current_note_duration = audio_duration_to_ms(2); + + } else { + note_resting = false; + + // TODO: handle glissando here (or remember previous and current tone) + /* there would need to be a freq(here we are) -> freq(next note) + * and do slide/glissando in between problem here is to know which + * frequency on the stack relates to what other? e.g. a melody starts + * tones in a sequence, and stops expiring one, so the most recently + * stopped is the starting point for a glissando to the most recently started? + * how to detect and preserve this relation? + * and what about user input, chords, ...? + */ + + // '- delta': Skip forward in the next note's length if we've over shot + // the last, so the overall length of the song is the same + uint16_t duration = audio_duration_to_ms((*notes_pointer)[current_note][1]); + + // Skip forward past any completely missed notes + while (delta > duration && current_note < notes_count - 1) { + delta -= duration; + current_note++; + duration = audio_duration_to_ms((*notes_pointer)[current_note][1]); + } + + if (delta < duration) { + duration -= delta; + } else { + // Only way to get here is if it is the last note and + // we have completely missed it. Play it for 1ms... + duration = 1; + } + + audio_play_note((*notes_pointer)[current_note][0], duration); + melody_current_note_duration = duration; + } + } + } + + if (playing_note) { +#ifdef AUDIO_ENABLE_TONE_MULTIPLEXING + tone_multiplexing_index_shift = (int)(current_time / tone_multiplexing_rate) % MIN(AUDIO_MAX_SIMULTANEOUS_TONES, active_tones); + goto_next_note = true; +#endif + if (vibrato || glissando) { + // force update on each cycle, since vibrato shifts the frequency slightly + goto_next_note = true; + } + + // housekeeping: stop notes that have no playtime left + for (int i = 0; i < active_tones; i++) { + if ((tones[i].duration != 0xffff) // indefinitely playing notes, started by 'audio_play_tone' + && (tones[i].duration != 0) // 'uninitialized' + ) { + if (timer_elapsed(tones[i].time_started) >= tones[i].duration) { + audio_stop_tone(tones[i].pitch); // also sets 'state_changed=true' + } + } + } + } + + // state-changes have a higher priority, always triggering the hardware to update + if (state_changed) { + state_changed = false; + return true; + } + + return goto_next_note; +} + +// Tone-multiplexing functions +#ifdef AUDIO_ENABLE_TONE_MULTIPLEXING +void audio_set_tone_multiplexing_rate(uint16_t rate) { tone_multiplexing_rate = rate; } +void audio_enable_tone_multiplexing(void) { tone_multiplexing_rate = AUDIO_TONE_MULTIPLEXING_RATE_DEFAULT; } +void audio_disable_tone_multiplexing(void) { tone_multiplexing_rate = 0; } +void audio_increase_tone_multiplexing_rate(uint16_t change) { + if ((0xffff - change) > tone_multiplexing_rate) { + tone_multiplexing_rate += change; + } +} +void audio_decrease_tone_multiplexing_rate(uint16_t change) { + if (change <= tone_multiplexing_rate) { + tone_multiplexing_rate -= change; + } +} +#endif + +// Tempo functions + +void audio_set_tempo(uint8_t tempo) { + if (tempo < 10) note_tempo = 10; + // else if (tempo > 250) + // note_tempo = 250; + else + note_tempo = tempo; +} + +void audio_increase_tempo(uint8_t tempo_change) { + if (tempo_change > 255 - note_tempo) + note_tempo = 255; + else + note_tempo += tempo_change; +} + +void audio_decrease_tempo(uint8_t tempo_change) { + if (tempo_change >= note_tempo - 10) + note_tempo = 10; + else + note_tempo -= tempo_change; +} + +// TODO in the int-math version are some bugs; songs sometimes abruptly end - maybe an issue with the timer/system-tick wrapping around? +uint16_t audio_duration_to_ms(uint16_t duration_bpm) { +#if defined(__AVR__) + // doing int-math saves us some bytes in the overall firmware size, but the intermediate result is less accurate before being cast to/returned as uint + return ((uint32_t)duration_bpm * 60 * 1000) / (64 * note_tempo); + // NOTE: beware of uint16_t overflows when note_tempo is low and/or the duration is long +#else + return ((float)duration_bpm * 60) / (64 * note_tempo) * 1000; +#endif +} +uint16_t audio_ms_to_duration(uint16_t duration_ms) { +#if defined(__AVR__) + return ((uint32_t)duration_ms * 64 * note_tempo) / 60 / 1000; +#else + return ((float)duration_ms * 64 * note_tempo) / 60 / 1000; +#endif +} |