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/* speaker control, uses timer2
*/
#include "common.h"
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
#include <stdbool.h>
#include <stdlib.h>
#include "speaker.h"
ISR(TIMER2_OVF_vect) {
PORTD ^= (1 << PD6);
}
void speakerInit () {
/* set PD6 to output */
DDRD |= (1 << PD6);
/* turn off */
PORTD = PORTD & ~(1 << PD6);
}
void speakerStart (const speakerMode mode) {
/* reset timer value */
TCNT2 = 0;
/* set normal mode */
TCCR2A = 0;
/* enable overflow interrupt */
TIMSK2 = (1 << TOIE2);
/* io clock with 1024 prescaler */
TCCR2B = ((TCCR2B & ~(1 << CS21)) | (1 << CS22) | (1 << CS20));
_delay_ms (50);
speakerStop ();
}
void speakerStop () {
/* zero clock source */
TCCR2B = 0;
/* turn off */
PORTD = PORTD & ~(1 << PD6);
}
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