diff options
Diffstat (limited to 'quantum/audio/audio.c')
-rw-r--r-- | quantum/audio/audio.c | 774 |
1 files changed, 322 insertions, 452 deletions
diff --git a/quantum/audio/audio.c b/quantum/audio/audio.c index e85370d958..3ca249fdf5 100644 --- a/quantum/audio/audio.c +++ b/quantum/audio/audio.c @@ -1,6 +1,6 @@ #include <stdio.h> #include <string.h> -#include <math.h> +//#include <math.h> #include <avr/pgmspace.h> #include <avr/interrupt.h> #include <avr/io.h> @@ -10,30 +10,28 @@ #include "eeconfig.h" -#ifdef VIBRATO_ENABLE - #include "vibrato_lut.h" -#endif +#define CPU_PRESCALER 8 -#define PI 3.14159265 +// ----------------------------------------------------------------------------- +// Timer Abstractions +// ----------------------------------------------------------------------------- -#define CPU_PRESCALER 8 +// 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) -#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 +// 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)); - float places[8] = {0, 0, 0, 0, 0, 0, 0, 0}; - uint16_t place_int = 0; - bool repeat = true; -#endif +// Fast PWM Mode Controls +#define TIMER_3_PERIOD ICR3 +#define TIMER_3_DUTY_CYCLE OCR3A + +// ----------------------------------------------------------------------------- -void delay_us(int count) { - while(count--) { - _delay_us(1); - } -} int voices = 0; int voice_place = 0; @@ -45,26 +43,23 @@ 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; -int max = 0xFF; -float sum = 0; float place = 0; uint8_t * sample; uint16_t sample_length = 0; -// float freq = 0; - -bool notes = false; -bool note = false; -float note_frequency = 0; -float note_length = 0; -float note_tempo = TEMPO_DEFAULT; -float note_timbre = TIMBRE_DEFAULT; + +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; +bool notes_repeat; +float notes_rest; +bool note_resting = false; uint8_t current_note = 0; uint8_t rest_counter = 0; @@ -77,175 +72,65 @@ float vibrato_rate = 0.125; float polyphony_rate = 0; -bool inited = false; +static bool audio_initialized = false; audio_config_t audio_config; uint16_t envelope_index = 0; -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 - -#endif - -// 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(float tempo) { - note_tempo = tempo; -} - -void decrease_tempo(uint8_t tempo_change) { - note_tempo += (float) tempo_change; -} - -void increase_tempo(uint8_t tempo_change) { - if (note_tempo - (float) tempo_change < 10) { - note_tempo = 10; - } else { - note_tempo -= (float) tempo_change; - } -} - -void audio_init() { +void audio_init() +{ - /* check signature */ - if (!eeconfig_is_enabled()) { + // 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 */ + // Set port PC6 (OC3A and /OC4A) as output + DDRC |= _BV(PORTC6); - /* 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; + DISABLE_AUDIO_COUNTER_3_ISR; - /* 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); + // 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); - 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 - - inited = true; + audio_initialized = true; } -void stop_all_notes() { - if (!inited) { +void stop_all_notes() +{ + if (!audio_initialized) { audio_init(); } voices = 0; - #ifdef PWM_AUDIO - TIMSK3 &= ~_BV(OCIE3A); - #else - TIMSK3 &= ~_BV(OCIE3A); - TCCR3A &= ~_BV(COM3A1); - #endif - notes = false; - note = false; + + DISABLE_AUDIO_COUNTER_3_ISR; + DISABLE_AUDIO_COUNTER_3_OUTPUT; + + playing_notes = false; + playing_note = false; frequency = 0; volume = 0; - for (int i = 0; i < 8; i++) { + for (uint8_t i = 0; i < 8; i++) + { frequencies[i] = 0; volumes[i] = 0; } } -void stop_note(float freq) { - if (note) { - if (!inited) { +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; @@ -266,15 +151,11 @@ void stop_note(float freq) { voice_place = 0; } if (voices == 0) { - #ifdef PWM_AUDIO - TIMSK3 &= ~_BV(OCIE3A); - #else - TIMSK3 &= ~_BV(OCIE3A); - TCCR3A &= ~_BV(COM3A1); - #endif + DISABLE_AUDIO_COUNTER_3_ISR; + DISABLE_AUDIO_COUNTER_3_OUTPUT; frequency = 0; volume = 0; - note = false; + playing_note = false; } } } @@ -289,9 +170,9 @@ float mod(float a, int b) float vibrato(float average_freq) { #ifdef VIBRATO_STRENGTH_ENABLE - float vibrated_freq = average_freq * pow(VIBRATO_LUT[(int)vibrato_counter], vibrato_strength); + float vibrated_freq = average_freq * pow(vibrato_lut[(int)vibrato_counter], vibrato_strength); #else - float vibrated_freq = average_freq * VIBRATO_LUT[(int)vibrato_counter]; + 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; @@ -299,309 +180,298 @@ float vibrato(float average_freq) { #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 (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; - } - } +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; + } +} - if (envelope_index < 65535) { - envelope_index++; - } - freq = voice_envelope(freq); +void play_note(float freq, int vol) { - if (freq < 30.517578125) - freq = 30.52; - ICR3 = (int)(((double)F_CPU) / (freq * CPU_PRESCALER)); // Set max to the period - OCR3A = (int)((((double)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); // Set compare to half the period - } - #endif + if (!audio_initialized) { + audio_init(); } - // 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) { - float freq; - - #ifdef VIBRATO_ENABLE - if (vibrato_strength > 0) { - freq = vibrato(note_frequency); - } else { - #else - { - #endif - freq = note_frequency; - } + if (audio_config.enable && voices < 8) { + DISABLE_AUDIO_COUNTER_3_ISR; - if (envelope_index < 65535) { - envelope_index++; - } - freq = voice_envelope(freq); + // Cancel notes if notes are playing + if (playing_notes) + stop_all_notes(); - ICR3 = (int)(((double)F_CPU) / (freq * CPU_PRESCALER)); // Set max to the period - OCR3A = (int)((((double)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); // Set compare to half the period - } else { - ICR3 = 0; - OCR3A = 0; - } - #endif - - - note_position++; - bool end_of_note = false; - if (ICR3 > 0) - end_of_note = (note_position >= (note_length / ICR3 * 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 - TIMSK3 &= ~_BV(OCIE3A); - #else - TIMSK3 &= ~_BV(OCIE3A); - TCCR3A &= ~_BV(COM3A1); - #endif - 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] * (note_tempo / 100); - #else - envelope_index = 0; - note_frequency = (*notes_pointer)[current_note][0]; - note_length = ((*notes_pointer)[current_note][1] / 4) * (note_tempo / 100); - #endif - } - note_position = 0; - } + 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; + } - if (!audio_config.enable) { - notes = false; - note = false; - } } -void play_note(float freq, int vol) { +void play_notes(float (*np)[][2], uint16_t n_count, bool n_repeat, float n_rest) +{ - if (!inited) { + if (!audio_initialized) { audio_init(); } -if (audio_config.enable && voices < 8) { - TIMSK3 &= ~_BV(OCIE3A); - // Cancel notes if notes are playing - if (notes) - stop_all_notes(); - note = true; - envelope_index = 0; - #ifdef PWM_AUDIO - freq = freq / SAMPLE_RATE; - #endif - if (freq > 0) { - frequencies[voices] = freq; - volumes[voices] = vol; - voices++; - } + 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; + } - #ifdef PWM_AUDIO - TIMSK3 |= _BV(OCIE3A); - #else - TIMSK3 |= _BV(OCIE3A); - TCCR3A |= _BV(COM3A1); - #endif } +bool is_playing_notes(void) { + return playing_notes; } -void play_notes(float (*np)[][2], uint16_t n_count, bool n_repeat, float n_rest) { +bool is_audio_on(void) { + return (audio_config.enable != 0); +} - if (!inited) { - audio_init(); - } +void audio_toggle(void) { + audio_config.enable ^= 1; + eeconfig_update_audio(audio_config.raw); + if (audio_config.enable) + audio_on_user(); +} -if (audio_config.enable) { - TIMSK3 &= ~_BV(OCIE3A); - // Cancel note if a note is playing - if (note) - stop_all_notes(); - 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] * (note_tempo / 100); - #else - note_frequency = (*notes_pointer)[current_note][0]; - note_length = ((*notes_pointer)[current_note][1] / 4) * (note_tempo / 100); - #endif - note_position = 0; +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 PWM_AUDIO - TIMSK3 |= _BV(OCIE3A); - #else - TIMSK3 |= _BV(OCIE3A); - TCCR3A |= _BV(COM3A1); - #endif +#ifdef VIBRATO_ENABLE + +// Vibrato rate functions + +void set_vibrato_rate(float rate) { + vibrato_rate = rate; } +void increase_vibrato_rate(float change) { + vibrato_rate *= change; } -#ifdef PWM_AUDIO -void play_sample(uint8_t * s, uint16_t l, bool r) { - if (!inited) { - audio_init(); - } +void decrease_vibrato_rate(float change) { + vibrato_rate /= change; +} - if (audio_config.enable) { - TIMSK3 &= ~_BV(OCIE3A); - stop_all_notes(); - place_int = 0; - sample = s; - sample_length = l; - repeat = r; +#ifdef VIBRATO_STRENGTH_ENABLE - TIMSK3 |= _BV(OCIE3A); - } +void set_vibrato_strength(float strength) { + vibrato_strength = strength; } -#endif -//------------------------------------------------------------------------------ -// Override these functions in your keymap file to play different tunes on -// startup and bootloader jump -__attribute__ ((weak)) -void play_startup_tone() -{ +void increase_vibrato_strength(float change) { + vibrato_strength *= change; } +void decrease_vibrato_strength(float change) { + vibrato_strength /= change; +} +#endif /* VIBRATO_STRENGTH_ENABLE */ -__attribute__ ((weak)) -void play_goodbye_tone() -{ +#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; + } } -//------------------------------------------------------------------------------ |