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- /* Copyright 2016 Jack Humbert
- *
- * 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 <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 PI 3.14159265
-
- #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));
-
-
- #define NOTE_PERIOD ICR3
- #define NOTE_DUTY_CYCLE OCR3A
-
-
- #ifdef PWM_AUDIO
- #include "wave.h"
- #define SAMPLE_DIVIDER 39
- #define SAMPLE_RATE (2000000.0/SAMPLE_DIVIDER/2048)
- // Resistor value of 1/ (2 * PI * 10nF * (2000000 hertz / SAMPLE_DIVIDER / 10)) for 10nF cap
-
- float places[8] = {0, 0, 0, 0, 0, 0, 0, 0};
- uint16_t place_int = 0;
- bool repeat = true;
- #endif
-
- void delay_us(int count) {
- while(count--) {
- _delay_us(1);
- }
- }
-
- 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;
- // float freq = 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();
-
- #ifdef PWM_AUDIO
-
- PLLFRQ = _BV(PDIV2);
- PLLCSR = _BV(PLLE);
- while(!(PLLCSR & _BV(PLOCK)));
- PLLFRQ |= _BV(PLLTM0); /* PCK 48MHz */
-
- /* Init a fast PWM on Timer4 */
- TCCR4A = _BV(COM4A0) | _BV(PWM4A); /* Clear OC4A on Compare Match */
- TCCR4B = _BV(CS40); /* No prescaling => f = PCK/256 = 187500Hz */
- OCR4A = 0;
-
- /* Enable the OC4A output */
- DDRC |= _BV(PORTC6);
-
- DISABLE_AUDIO_COUNTER_3_ISR; // Turn off 3A interputs
-
- TCCR3A = 0x0; // Options not needed
- TCCR3B = _BV(CS31) | _BV(CS30) | _BV(WGM32); // 64th prescaling and CTC
- OCR3A = SAMPLE_DIVIDER - 1; // Correct count/compare, related to sample playback
-
- #else
-
- // 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);
-
- #endif
-
- audio_initialized = true;
- }
-
- void stop_all_notes() {
- if (!audio_initialized) {
- audio_init();
- }
- voices = 0;
- #ifdef PWM_AUDIO
- DISABLE_AUDIO_COUNTER_3_ISR;
- #else
- DISABLE_AUDIO_COUNTER_3_ISR;
- DISABLE_AUDIO_COUNTER_3_OUTPUT;
- #endif
-
- 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();
- }
- #ifdef PWM_AUDIO
- freq = freq / SAMPLE_RATE;
- #endif
- 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) {
- #ifdef PWM_AUDIO
- DISABLE_AUDIO_COUNTER_3_ISR;
- #else
- DISABLE_AUDIO_COUNTER_3_ISR;
- DISABLE_AUDIO_COUNTER_3_OUTPUT;
- #endif
- 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)
- {
- if (playing_note) {
- #ifdef PWM_AUDIO
- if (voices == 1) {
- // SINE
- OCR4A = pgm_read_byte(&sinewave[(uint16_t)place]) >> 2;
-
- // SQUARE
- // if (((int)place) >= 1024){
- // OCR4A = 0xFF >> 2;
- // } else {
- // OCR4A = 0x00;
- // }
-
- // SAWTOOTH
- // OCR4A = (int)place / 4;
-
- // TRIANGLE
- // if (((int)place) >= 1024) {
- // OCR4A = (int)place / 2;
- // } else {
- // OCR4A = 2048 - (int)place / 2;
- // }
-
- place += frequency;
-
- if (place >= SINE_LENGTH)
- place -= SINE_LENGTH;
-
- } else {
- int sum = 0;
- for (int i = 0; i < voices; i++) {
- // SINE
- sum += pgm_read_byte(&sinewave[(uint16_t)places[i]]) >> 2;
-
- // SQUARE
- // if (((int)places[i]) >= 1024){
- // sum += 0xFF >> 2;
- // } else {
- // sum += 0x00;
- // }
-
- places[i] += frequencies[i];
-
- if (places[i] >= SINE_LENGTH)
- places[i] -= SINE_LENGTH;
- }
- OCR4A = sum;
- }
- #else
- if (voices > 0) {
- float freq;
- 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 {
- #else
- {
- #endif
- freq = frequencies[voice_place];
- }
- } 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 {
- #else
- {
- #endif
- freq = frequency;
- }
- }
-
- if (envelope_index < 65535) {
- envelope_index++;
- }
- freq = voice_envelope(freq);
-
- if (freq < 30.517578125)
- freq = 30.52;
- NOTE_PERIOD = (int)(((double)F_CPU) / (freq * CPU_PRESCALER)); // Set max to the period
- NOTE_DUTY_CYCLE = (int)((((double)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); // Set compare to half the period
- }
- #endif
- }
-
- // SAMPLE
- // OCR4A = pgm_read_byte(&sample[(uint16_t)place_int]);
-
- // place_int++;
-
- // if (place_int >= sample_length)
- // if (repeat)
- // place_int -= sample_length;
- // else
- // DISABLE_AUDIO_COUNTER_3_ISR;
-
-
- if (playing_notes) {
- #ifdef PWM_AUDIO
- OCR4A = pgm_read_byte(&sinewave[(uint16_t)place]) >> 0;
-
- place += note_frequency;
- if (place >= SINE_LENGTH)
- place -= SINE_LENGTH;
- #else
- if (note_frequency > 0) {
- float freq;
-
- #ifdef VIBRATO_ENABLE
- if (vibrato_strength > 0) {
- freq = vibrato(note_frequency);
- } else {
- #else
- {
- #endif
- freq = note_frequency;
- }
-
- if (envelope_index < 65535) {
- envelope_index++;
- }
- freq = voice_envelope(freq);
-
- NOTE_PERIOD = (int)(((double)F_CPU) / (freq * CPU_PRESCALER)); // Set max to the period
- NOTE_DUTY_CYCLE = (int)((((double)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); // Set compare to half the period
- } else {
- NOTE_PERIOD = 0;
- NOTE_DUTY_CYCLE = 0;
- }
- #endif
-
-
- note_position++;
- bool end_of_note = false;
- if (NOTE_PERIOD > 0)
- end_of_note = (note_position >= (note_length / NOTE_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 {
- #ifdef PWM_AUDIO
- DISABLE_AUDIO_COUNTER_3_ISR;
- #else
- DISABLE_AUDIO_COUNTER_3_ISR;
- DISABLE_AUDIO_COUNTER_3_OUTPUT;
- #endif
- 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;
- #ifdef PWM_AUDIO
- note_frequency = (*notes_pointer)[current_note][0] / SAMPLE_RATE;
- note_length = (*notes_pointer)[current_note][1] * (((float)note_tempo) / 100);
- #else
- envelope_index = 0;
- note_frequency = (*notes_pointer)[current_note][0];
- note_length = ((*notes_pointer)[current_note][1] / 4) * (((float)note_tempo) / 100);
- #endif
- }
- 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;
-
- #ifdef PWM_AUDIO
- freq = freq / SAMPLE_RATE;
- #endif
- if (freq > 0) {
- frequencies[voices] = freq;
- volumes[voices] = vol;
- voices++;
- }
-
- #ifdef PWM_AUDIO
- ENABLE_AUDIO_COUNTER_3_ISR;
- #else
- ENABLE_AUDIO_COUNTER_3_ISR;
- ENABLE_AUDIO_COUNTER_3_OUTPUT;
- #endif
- }
-
- }
-
- 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;
-
- #ifdef PWM_AUDIO
- note_frequency = (*notes_pointer)[current_note][0] / SAMPLE_RATE;
- note_length = (*notes_pointer)[current_note][1] * (((float)note_tempo) / 100);
- #else
- note_frequency = (*notes_pointer)[current_note][0];
- note_length = ((*notes_pointer)[current_note][1] / 4) * (((float)note_tempo) / 100);
- #endif
- note_position = 0;
-
-
- #ifdef PWM_AUDIO
- ENABLE_AUDIO_COUNTER_3_ISR;
- #else
- ENABLE_AUDIO_COUNTER_3_ISR;
- ENABLE_AUDIO_COUNTER_3_OUTPUT;
- #endif
- }
-
- }
-
- #ifdef PWM_AUDIO
- void play_sample(uint8_t * s, uint16_t l, bool r) {
- if (!audio_initialized) {
- audio_init();
- }
-
- if (audio_config.enable) {
- DISABLE_AUDIO_COUNTER_3_ISR;
- stop_all_notes();
- place_int = 0;
- sample = s;
- sample_length = l;
- repeat = r;
-
- ENABLE_AUDIO_COUNTER_3_ISR;
- }
- }
- #endif
-
-
- void audio_toggle(void) {
- audio_config.enable ^= 1;
- eeconfig_update_audio(audio_config.raw);
- }
-
- void audio_on(void) {
- audio_config.enable = 1;
- eeconfig_update_audio(audio_config.raw);
- }
-
- 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;
- }
- }
-
-
- //------------------------------------------------------------------------------
- // Override these functions in your keymap file to play different tunes on
- // startup and bootloader jump
- __attribute__ ((weak))
- void play_startup_tone()
- {
- }
-
- __attribute__ ((weak))
- void play_goodbye_tone()
- {
- }
- //------------------------------------------------------------------------------
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