Button.c

/*Button*/
#include <avr/io.h>
#include <util/delay.h>

#define F_CPU 16000000UL

int main(void)
{
    DDRD &= ~_BV(DDD2); //Set as input
    DDRB |= _BV(DDB5); // set as output
    PORTB= 0x00;

    while(1)
    {
        if(bit_is_set(PIND,PIND2))
        {
            PORTB|= _BV(PORTB5); // to set buzzer

        }
        else
        {
            PORTB &= ~_BV(PORTB5);
        }
    }

}