Clarified audio.c (#302)

* Updated personal layouts

* tweaked personal

* Nightly - Audio Cleanup

Refactored the LUTs. Abstracted some of the registers out of audio to
use more functional names. Split audio into audio and audio_pwm. WIP

* nightly - collapsed code

* Added check for note playing to LEDs

1 files changed, 643 insertions, 0 deletions

diff --git a/quantum/audio/audio_pwm.c b/quantum/audio/audio_pwm.c
new file mode 100644
index 000000000..328a253a7
--- /dev/null
+++ b/quantum/audio/audio_pwm.c
@@ -0,0 +1,643 @@
+#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_common.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()
+{
+}
+//------------------------------------------------------------------------------