URS_K02G02Z02

#define F_CPU 7372800UL

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

uint8_t state = 1;

void blink(uint8_t cnt) {
    if (cnt <= 3) {
        PORTA = PORTA & ~_BV(4+cnt) & ~_BV(3-cnt);
    } else {
        cnt %= 4;
        PORTA = PORTA | _BV(cnt) | _BV(7-cnt);
    }
}

int main() {
    DDRA = 0xff;
    PORTA = 0xff;

    DDRB = _BV(0) | _BV(1);
    PORTB = _BV(0) | _BV(1);

    uint8_t cnt = 0;

    while (1) {
        if(bit_is_clear(PINB, 0)) {
            state = -1;
        } else if (bit_is_clear(PINB, 1)) {
            state = 1;
        }

        if(state == 1) {
            blink(cnt);
            cnt = (cnt+1) % 8;
        }
        _delay_ms(200);
    }
}