pentabug/old_firmware/lib/music.c

#include <stdint.h>
#include <math.h>
#include <avr/interrupt.h>
#include <avr/common.h>
#include <avr/io.h>
#include "util.h"
#include "bughal.h"
#include "music.h"

//static volatile uint16_t currentNote;

void music_init(void) {

	TCCR1A = 0; //TIMER1, normal, no PWM
	TCCR1B = (1 << WGM12) | (1 << CS11); //CTC Mode, Clear Timer on Compare, Prescaler = 8
	TIMSK1 &= ~(1 << OCIE1A); //disable Output Compare Interrupt
	return;
}
;

void music_setNote(uint16_t note, uint8_t octave) {

	cli();
	if (note != NOTE_PAUSE) {
		//Play a Note
		buzzr_up();
		TIMSK1 |= (1 << OCIE1A); //enable Output Compare Interrupt
		OCR1A = octave == 0 ? note : note / (1 << octave);
	} else { // Pause (silence)
		buzzr_off();
		TIMSK1 &= ~(1 << OCIE1A); //disable Output Compare Interrupt
	}
	sei();
	return;
}

/* timer interrupt function */ISR(TIMER1_COMPA_vect, ISR_NOBLOCK) {

	// invert buzzer polarity
	buzzr_inv();

}