#include <avr/io.h>

#define	LED1	_BV(PB0)
#define	LED2	_BV(PB1)
#define	LED3	_BV(PB2)
#define	LED4	_BV(PB3)
#define	LED5	_BV(PB4)

#define ON(x)	PORTB &= ~(x)
#define OFF(x)	PORTB |= (x)

#define DELAY	for (i = 50000; i--; ) asm("nop")

int main()
{
	DDRB = 0xFF;
	PORTB = 0b00011111;

	while (1)
	{
		ON(LED1); DELAY; OFF(LED1);
		ON(LED2); DELAY; OFF(LED2);
		ON(LED3); DELAY; OFF(LED3);
		ON(LED4); DELAY; OFF(LED4);
		ON(LED5); DELAY; OFF(LED5);
		ON(LED4); DELAY; OFF(LED4);
		ON(LED3); DELAY; OFF(LED3);
		ON(LED2); DELAY; OFF(LED2);
	}
}