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;
+    }
+}