اینم برنامه :
#include <mega16.h>
#include <delay.h>
#define B PORTB
#define D PORTD
#define A PORTA
char i;
char x;
char z;
void main(void)
{
PORTA=0x00;
DDRA=0x0F;
PORTB=0x00;
DDRB=0xff;
PORTD=0x00;
DDRD=0xFf;

while (1)
{
i=0x55; //1
B=i;
D=i;
delay_ms(50);
B=B<<1;
D=D<<1;
delay_ms(50);
x=0X0F; //2
A=x;
delay_ms(50);
x=0X00;
A=x;
delay_ms(50);
}
}