blink help

blink.c

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

void init_io(void)
{
        // 1 = output, 0 = input
        DDRB = 0b11111111; // All outputs
        DDRC = 0b11111111; // All outputs
        DDRD = 0b11111110; // PORTD (RX on PD0). Just for demo
}

void blink_s(void)
{
        PORTC = 0xFF;
        PORTB = 0xFF;
        PORTD = 0xFF;
        _delay_ms(250);
        PORTC = 0x00;
        PORTB = 0x00;
        PORTD = 0x00;
        _delay_ms(250);
}
void blink_l(void)
{
        PORTC = 0xFF;
        PORTB = 0xFF;
        PORTD = 0xFF;
        _delay_ms(500);
        PORTC = 0x00;
        PORTB = 0x00;
        PORTD = 0x00;
        _delay_ms(500);
}


int main(void)
{
        init_io();

        while (1)
        {
                blink_s();
                blink_s();
                blink_s();
                blink_l();
                blink_l();
                blink_l();
                blink_s();
                blink_s();
                blink_s();
                _delay_ms(1000);
        }

        return 0;
}