#define F_CPU 8000000UL

#include <avr/io.h>

int main(void) {
    DDRB = 0xff; /* output to leds */
    DDRD = 0x00; /* input from switches */
    PORTD = 0xff; /* pull up */
    
    for (;;) {
	PORTB = PIND;
    }
}