organ.c

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#include "includes/CPU.h"
#include <avr/io.h>
#include <util/delay.h>
#include "includes/organ.h"
#include "includes/pinDefines.h"
 
void playNote(uint16_t half_us, uint16_t duration_ms)
{
    /* Calculate the number of complete cycles needed
     * Optimized formula: (0.5e6 / half_us) * duration_ms / 1000
     * Equivalent to: cycles = frequency_Hz * (duration_ms/1000)
     */
    uint16_t cycles = (500000 / half_us) * duration_ms / 1000;
 
    /* Main tone generation loop */
    for (uint16_t i = 0; i < cycles; i++)
    {
        /* HIGH phase of square wave */
        BUZZER_PORT |= (1 << BUZZER_PIN);      /* Set pin high */
        for (uint16_t k = 0; k < half_us; k++) /* Half cycle delay */
            _delay_us(1);
 
        /* LOW phase of square wave */
        BUZZER_PORT &= ~(1 << BUZZER_PIN);     /* Set pin low */
        for (uint16_t m = 0; m < half_us; m++) /* Half cycle delay */
            _delay_us(1);
    }
 
    /* Short pause between notes to eliminate transition noise */
    _delay_ms(30);
}
 
void rest(uint16_t duration)
{
    for (uint16_t i = 0; i < duration; i++)
        _delay_ms(1);
}