URS_L07Z06

#define F_CPU 7372800UL

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

void blink(uint8_t cnt) {
    if (cnt == 0) {
        PORTA = 0xff;
    } else if (cnt % 2 == 1) {
        PORTA = ~_BV(cnt/2);
    } else {
        PORTA = ~_BV(8-cnt/2);
    }
}

int main(void) {
    DDRA = 0xff;
    PORTA = 0xff;
    uint8_t cnt = 0;

    while (1) {
        blink(cnt);
        cnt = (cnt + 1) % 9;
    //  _delay_ms(325);
    }
}