#include <stdio.h> #include <string.h> #include <math.h> #include <avr/pgmspace.h> #include <avr/interrupt.h> #include <avr/io.h> #include "audio.h" #include "keymap_common.h" #define PI 3.14159265 // #define PWM_AUDIO #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 #endif void delay_us(int count) { while(count--) { _delay_us(1); } } int voices = 0; int voice_place = 0; double frequency = 0; int volume = 0; long position = 0; double frequencies[8] = {0, 0, 0, 0, 0, 0, 0, 0}; int volumes[8] = {0, 0, 0, 0, 0, 0, 0, 0}; bool sliding = false; int max = 0xFF; float sum = 0; int value = 128; float place = 0; float places[8] = {0, 0, 0, 0, 0, 0, 0, 0}; uint16_t place_int = 0; bool repeat = true; uint8_t * sample; uint16_t sample_length = 0; bool notes = false; bool note = false; float note_frequency = 0; float note_length = 0; uint16_t note_position = 0; float (* notes_pointer)[][2]; uint8_t notes_length; bool notes_repeat; uint8_t current_note = 0; void stop_all_notes() { voices = 0; #ifdef PWM_AUDIO TIMSK3 &= ~_BV(OCIE3A); #else TIMSK3 &= ~_BV(OCIE3A); TCCR3A &= ~_BV(COM3A1); #endif notes = false; note = false; frequency = 0; volume = 0; for (int i = 0; i < 8; i++) { frequencies[i] = 0; volumes[i] = 0; } } void stop_note(double freq) { #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; } } } voices--; if (voices < 0) voices = 0; if (voices == 0) { #ifdef PWM_AUDIO TIMSK3 &= ~_BV(OCIE3A); #else TIMSK3 &= ~_BV(OCIE3A); TCCR3A &= ~_BV(COM3A1); #endif frequency = 0; volume = 0; note = false; } else { double freq = frequencies[voices - 1]; int vol = volumes[voices - 1]; double starting_f = frequency; if (frequency < freq) { sliding = true; for (double f = starting_f; f <= freq; f += ((freq - starting_f) / 2000.0)) { frequency = f; } sliding = false; } else if (frequency > freq) { sliding = true; for (double f = starting_f; f >= freq; f -= ((starting_f - freq) / 2000.0)) { frequency = f; } sliding = false; } frequency = freq; volume = vol; } } void init_notes() { #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); TIMSK3 &= ~_BV(OCIE3A); // 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 DDRC |= _BV(PORTC6); TIMSK3 &= ~_BV(OCIE3A); // Turn off 3A interputs TCCR3A = (0 << COM3A1) | (0 << COM3A0) | (1 << WGM31) | (0 << WGM30); TCCR3B = (1 << WGM33) | (1 << WGM32) | (0 << CS32) | (1 << CS31) | (0 << CS30); #endif } ISR(TIMER3_COMPA_vect) { if (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 (frequency > 0) { // ICR3 = (int)(((double)F_CPU) / frequency); // Set max to the period // OCR3A = (int)(((double)F_CPU) / frequency) >> 1; // Set compare to half the period if (place > 10) { voice_place = (voice_place + 1) % voices; place = 0.0; } ICR3 = (int)(((double)F_CPU) / frequencies[voice_place]); // Set max to the period OCR3A = (int)(((double)F_CPU) / frequencies[voice_place]) >> 1; // Set compare to half the period place++; } #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 // TIMSK3 &= ~_BV(OCIE3A); if (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) { ICR3 = (int)(((double)F_CPU) / note_frequency); // Set max to the period OCR3A = (int)(((double)F_CPU) / note_frequency) >> 1; // Set compare to half the period } else { ICR3 = 0; OCR3A = 0; } #endif note_position++; if (note_position >= note_length) { current_note++; if (current_note >= notes_length) { if (notes_repeat) { current_note = 0; } else { #ifdef PWM_AUDIO TIMSK3 &= ~_BV(OCIE3A); #else TIMSK3 &= ~_BV(OCIE3A); TCCR3A &= ~_BV(COM3A1); #endif notes = false; return; } } #ifdef PWM_AUDIO note_frequency = (*notes_pointer)[current_note][0] / SAMPLE_RATE; note_length = (*notes_pointer)[current_note][1]; #else note_frequency = (*notes_pointer)[current_note][0]; note_length = (*notes_pointer)[current_note][1] / 4; #endif note_position = 0; } } } void play_notes(float (*np)[][2], uint8_t n_length, bool n_repeat) { if (note) stop_all_notes(); notes = true; notes_pointer = np; notes_length = n_length; notes_repeat = n_repeat; place = 0; current_note = 0; #ifdef PWM_AUDIO note_frequency = (*notes_pointer)[current_note][0] / SAMPLE_RATE; note_length = (*notes_pointer)[current_note][1]; #else note_frequency = (*notes_pointer)[current_note][0]; note_length = (*notes_pointer)[current_note][1] / 4; #endif note_position = 0; #ifdef PWM_AUDIO TIMSK3 |= _BV(OCIE3A); #else TIMSK3 |= _BV(OCIE3A); TCCR3A |= _BV(COM3A1); #endif } void play_sample(uint8_t * s, uint16_t l, bool r) { stop_all_notes(); place_int = 0; sample = s; sample_length = l; repeat = r; #ifdef PWM_AUDIO TIMSK3 |= _BV(OCIE3A); #else #endif } void play_note(double freq, int vol) { if (notes) stop_all_notes(); note = true; #ifdef PWM_AUDIO freq = freq / SAMPLE_RATE; #endif if (freq > 0) { if (frequency != 0) { double starting_f = frequency; if (frequency < freq) { for (double f = starting_f; f <= freq; f += ((freq - starting_f) / 2000.0)) { frequency = f; } } else if (frequency > freq) { for (double f = starting_f; f >= freq; f -= ((starting_f - freq) / 2000.0)) { frequency = f; } } } frequency = freq; volume = vol; frequencies[voices] = frequency; volumes[voices] = volume; voices++; } #ifdef PWM_AUDIO TIMSK3 |= _BV(OCIE3A); #else TIMSK3 |= _BV(OCIE3A); TCCR3A |= _BV(COM3A1); #endif }