diff options
Diffstat (limited to 'quantum/audio/audio.c')
-rw-r--r-- | quantum/audio/audio.c | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/quantum/audio/audio.c b/quantum/audio/audio.c new file mode 100644 index 000000000..ead5fbf3e --- /dev/null +++ b/quantum/audio/audio.c @@ -0,0 +1,477 @@ +#include <stdio.h> +#include <string.h> +//#include <math.h> +#include <avr/pgmspace.h> +#include <avr/interrupt.h> +#include <avr/io.h> +#include "print.h" +#include "audio.h" +#include "keymap.h" + +#include "eeconfig.h" + +#define CPU_PRESCALER 8 + +// ----------------------------------------------------------------------------- +// Timer Abstractions +// ----------------------------------------------------------------------------- + +// TIMSK3 - Timer/Counter #3 Interrupt Mask Register +// Turn on/off 3A interputs, stopping/enabling the ISR calls +#define ENABLE_AUDIO_COUNTER_3_ISR TIMSK3 |= _BV(OCIE3A) +#define DISABLE_AUDIO_COUNTER_3_ISR TIMSK3 &= ~_BV(OCIE3A) + +// TCCR3A: Timer/Counter #3 Control Register +// Compare Output Mode (COM3An) = 0b00 = Normal port operation, OC3A disconnected from PC6 +#define ENABLE_AUDIO_COUNTER_3_OUTPUT TCCR3A |= _BV(COM3A1); +#define DISABLE_AUDIO_COUNTER_3_OUTPUT TCCR3A &= ~(_BV(COM3A1) | _BV(COM3A0)); + +// Fast PWM Mode Controls +#define TIMER_3_PERIOD ICR3 +#define TIMER_3_DUTY_CYCLE OCR3A + +// ----------------------------------------------------------------------------- + + +int voices = 0; +int voice_place = 0; +float frequency = 0; +int volume = 0; +long position = 0; + +float frequencies[8] = {0, 0, 0, 0, 0, 0, 0, 0}; +int volumes[8] = {0, 0, 0, 0, 0, 0, 0, 0}; +bool sliding = false; + +float place = 0; + +uint8_t * sample; +uint16_t sample_length = 0; + +bool playing_notes = false; +bool playing_note = false; +float note_frequency = 0; +float note_length = 0; +uint8_t note_tempo = TEMPO_DEFAULT; +float note_timbre = TIMBRE_DEFAULT; +uint16_t note_position = 0; +float (* notes_pointer)[][2]; +uint16_t notes_count; +bool notes_repeat; +float notes_rest; +bool note_resting = false; + +uint8_t current_note = 0; +uint8_t rest_counter = 0; + +#ifdef VIBRATO_ENABLE +float vibrato_counter = 0; +float vibrato_strength = .5; +float vibrato_rate = 0.125; +#endif + +float polyphony_rate = 0; + +static bool audio_initialized = false; + +audio_config_t audio_config; + +uint16_t envelope_index = 0; + +void audio_init() +{ + + // Check EEPROM + if (!eeconfig_is_enabled()) + { + eeconfig_init(); + } + audio_config.raw = eeconfig_read_audio(); + + // Set port PC6 (OC3A and /OC4A) as output + DDRC |= _BV(PORTC6); + + DISABLE_AUDIO_COUNTER_3_ISR; + + // TCCR3A / TCCR3B: Timer/Counter #3 Control Registers + // Compare Output Mode (COM3An) = 0b00 = Normal port operation, OC3A disconnected from PC6 + // Waveform Generation Mode (WGM3n) = 0b1110 = Fast PWM Mode 14 (Period = ICR3, Duty Cycle = OCR3A) + // Clock Select (CS3n) = 0b010 = Clock / 8 + TCCR3A = (0 << COM3A1) | (0 << COM3A0) | (1 << WGM31) | (0 << WGM30); + TCCR3B = (1 << WGM33) | (1 << WGM32) | (0 << CS32) | (1 << CS31) | (0 << CS30); + + audio_initialized = true; +} + +void stop_all_notes() +{ + if (!audio_initialized) { + audio_init(); + } + voices = 0; + + DISABLE_AUDIO_COUNTER_3_ISR; + DISABLE_AUDIO_COUNTER_3_OUTPUT; + + playing_notes = false; + playing_note = false; + frequency = 0; + volume = 0; + + for (uint8_t i = 0; i < 8; i++) + { + frequencies[i] = 0; + volumes[i] = 0; + } +} + +void stop_note(float freq) +{ + if (playing_note) { + if (!audio_initialized) { + audio_init(); + } + for (int i = 7; i >= 0; i--) { + if (frequencies[i] == freq) { + frequencies[i] = 0; + volumes[i] = 0; + for (int j = i; (j < 7); j++) { + frequencies[j] = frequencies[j+1]; + frequencies[j+1] = 0; + volumes[j] = volumes[j+1]; + volumes[j+1] = 0; + } + break; + } + } + voices--; + if (voices < 0) + voices = 0; + if (voice_place >= voices) { + voice_place = 0; + } + if (voices == 0) { + DISABLE_AUDIO_COUNTER_3_ISR; + DISABLE_AUDIO_COUNTER_3_OUTPUT; + frequency = 0; + volume = 0; + playing_note = false; + } + } +} + +#ifdef VIBRATO_ENABLE + +float mod(float a, int b) +{ + float r = fmod(a, b); + return r < 0 ? r + b : r; +} + +float vibrato(float average_freq) { + #ifdef VIBRATO_STRENGTH_ENABLE + float vibrated_freq = average_freq * pow(vibrato_lut[(int)vibrato_counter], vibrato_strength); + #else + float vibrated_freq = average_freq * vibrato_lut[(int)vibrato_counter]; + #endif + vibrato_counter = mod((vibrato_counter + vibrato_rate * (1.0 + 440.0/average_freq)), VIBRATO_LUT_LENGTH); + return vibrated_freq; +} + +#endif + +ISR(TIMER3_COMPA_vect) +{ + float freq; + + if (playing_note) { + if (voices > 0) { + if (polyphony_rate > 0) { + if (voices > 1) { + voice_place %= voices; + if (place++ > (frequencies[voice_place] / polyphony_rate / CPU_PRESCALER)) { + voice_place = (voice_place + 1) % voices; + place = 0.0; + } + } + + #ifdef VIBRATO_ENABLE + if (vibrato_strength > 0) { + freq = vibrato(frequencies[voice_place]); + } else { + freq = frequencies[voice_place]; + } + #else + freq = frequencies[voice_place]; + #endif + } else { + if (frequency != 0 && frequency < frequencies[voices - 1] && frequency < frequencies[voices - 1] * pow(2, -440/frequencies[voices - 1]/12/2)) { + frequency = frequency * pow(2, 440/frequency/12/2); + } else if (frequency != 0 && frequency > frequencies[voices - 1] && frequency > frequencies[voices - 1] * pow(2, 440/frequencies[voices - 1]/12/2)) { + frequency = frequency * pow(2, -440/frequency/12/2); + } else { + frequency = frequencies[voices - 1]; + } + + #ifdef VIBRATO_ENABLE + if (vibrato_strength > 0) { + freq = vibrato(frequency); + } else { + freq = frequency; + } + #else + freq = frequency; + #endif + } + + if (envelope_index < 65535) { + envelope_index++; + } + + freq = voice_envelope(freq); + + if (freq < 30.517578125) { + freq = 30.52; + } + + TIMER_3_PERIOD = (uint16_t)(((float)F_CPU) / (freq * CPU_PRESCALER)); + TIMER_3_DUTY_CYCLE = (uint16_t)((((float)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); + } + } + + if (playing_notes) { + if (note_frequency > 0) { + #ifdef VIBRATO_ENABLE + if (vibrato_strength > 0) { + freq = vibrato(note_frequency); + } else { + freq = note_frequency; + } + #else + freq = note_frequency; + #endif + + if (envelope_index < 65535) { + envelope_index++; + } + freq = voice_envelope(freq); + + TIMER_3_PERIOD = (uint16_t)(((float)F_CPU) / (freq * CPU_PRESCALER)); + TIMER_3_DUTY_CYCLE = (uint16_t)((((float)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); + } else { + TIMER_3_PERIOD = 0; + TIMER_3_DUTY_CYCLE = 0; + } + + note_position++; + bool end_of_note = false; + if (TIMER_3_PERIOD > 0) { + end_of_note = (note_position >= (note_length / TIMER_3_PERIOD * 0xFFFF)); + } else { + end_of_note = (note_position >= (note_length * 0x7FF)); + } + + if (end_of_note) { + current_note++; + if (current_note >= notes_count) { + if (notes_repeat) { + current_note = 0; + } else { + DISABLE_AUDIO_COUNTER_3_ISR; + DISABLE_AUDIO_COUNTER_3_OUTPUT; + playing_notes = false; + return; + } + } + if (!note_resting && (notes_rest > 0)) { + note_resting = true; + note_frequency = 0; + note_length = notes_rest; + current_note--; + } else { + note_resting = false; + envelope_index = 0; + note_frequency = (*notes_pointer)[current_note][0]; + note_length = ((*notes_pointer)[current_note][1] / 4) * (((float)note_tempo) / 100); + } + + note_position = 0; + } + } + + if (!audio_config.enable) { + playing_notes = false; + playing_note = false; + } +} + +void play_note(float freq, int vol) { + + if (!audio_initialized) { + audio_init(); + } + + if (audio_config.enable && voices < 8) { + DISABLE_AUDIO_COUNTER_3_ISR; + + // Cancel notes if notes are playing + if (playing_notes) + stop_all_notes(); + + playing_note = true; + + envelope_index = 0; + + if (freq > 0) { + frequencies[voices] = freq; + volumes[voices] = vol; + voices++; + } + + ENABLE_AUDIO_COUNTER_3_ISR; + ENABLE_AUDIO_COUNTER_3_OUTPUT; + } + +} + +void play_notes(float (*np)[][2], uint16_t n_count, bool n_repeat, float n_rest) +{ + + if (!audio_initialized) { + audio_init(); + } + + if (audio_config.enable) { + + DISABLE_AUDIO_COUNTER_3_ISR; + + // Cancel note if a note is playing + if (playing_note) + stop_all_notes(); + + playing_notes = true; + + notes_pointer = np; + notes_count = n_count; + notes_repeat = n_repeat; + notes_rest = n_rest; + + place = 0; + current_note = 0; + + note_frequency = (*notes_pointer)[current_note][0]; + note_length = ((*notes_pointer)[current_note][1] / 4) * (((float)note_tempo) / 100); + note_position = 0; + + + ENABLE_AUDIO_COUNTER_3_ISR; + ENABLE_AUDIO_COUNTER_3_OUTPUT; + } + +} + +bool is_playing_notes(void) { + return playing_notes; +} + +bool is_audio_on(void) { + return (audio_config.enable != 0); +} + +void audio_toggle(void) { + 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(); +} + +void audio_off(void) { + audio_config.enable = 0; + eeconfig_update_audio(audio_config.raw); +} + +#ifdef VIBRATO_ENABLE + +// Vibrato rate functions + +void set_vibrato_rate(float rate) { + vibrato_rate = rate; +} + +void increase_vibrato_rate(float change) { + vibrato_rate *= change; +} + +void decrease_vibrato_rate(float change) { + vibrato_rate /= change; +} + +#ifdef VIBRATO_STRENGTH_ENABLE + +void set_vibrato_strength(float strength) { + vibrato_strength = strength; +} + +void increase_vibrato_strength(float change) { + vibrato_strength *= change; +} + +void decrease_vibrato_strength(float change) { + vibrato_strength /= change; +} + +#endif /* VIBRATO_STRENGTH_ENABLE */ + +#endif /* VIBRATO_ENABLE */ + +// Polyphony functions + +void set_polyphony_rate(float rate) { + polyphony_rate = rate; +} + +void enable_polyphony() { + polyphony_rate = 5; +} + +void disable_polyphony() { + polyphony_rate = 0; +} + +void increase_polyphony_rate(float change) { + polyphony_rate *= change; +} + +void decrease_polyphony_rate(float change) { + polyphony_rate /= change; +} + +// Timbre function + +void set_timbre(float timbre) { + note_timbre = timbre; +} + +// Tempo functions + +void set_tempo(uint8_t tempo) { + note_tempo = tempo; +} + +void decrease_tempo(uint8_t tempo_change) { + note_tempo += tempo_change; +} + +void increase_tempo(uint8_t tempo_change) { + if (note_tempo - tempo_change < 10) { + note_tempo = 10; + } else { + note_tempo -= tempo_change; + } +} |