Joystick Elo

/*
 * DawidTomaszewski3.c
 *
 * Created: 2018-01-10 08:55:34
 *  Author: C245
 */


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

#define d1 0
#define d2 1
#define d3 2
#define d4 3
#define d5 4
#define d6 5
#define d7 6
#define d8 7

int i = -1;
int a = 0;
int b = 0;


void setup(){
    DDRD |= (1<<d1);
    DDRD |= (1<<d2);
    DDRD |= (1<<d3);
    DDRD |= (1<<d4);
    DDRD |= (1<<d5);
    DDRD |= (1<<d6);
    DDRD |= (1<<d7);
    DDRD |= (1<<d8);

    PORTD |=(1<<d1);
    PORTD |=(1<<d2);
    PORTD |=(1<<d3);
    PORTD |=(1<<d4);
    PORTD |=(1<<d5);
    PORTD |=(1<<d6);
    PORTD |=(1<<d7);
    PORTD |=(1<<d8);


    DDRC &=~(1<<0);

    ADMUX |= (1<<REFS0);
    ADCSRA |=(1<<ADEN) | (1<<ADSC) | (1<<ADPS2) | (1<<ADPS0) | (1<<ADIE);



}



void loop(){
int AC = ADC;
if(AC < 600 && AC > 400) a = 0;
else if (AC > 1000) a = 1;
else if(AC < 40) a = 2;
//_delay_ms(20);
switch(a){
    case 0:
    b=0;
    break;
    case 1:
    if (b==0)
    {
        i++;
        PORTD &= ~(1<<i);
        b=1;
    }
    else
    {
        b=1;
    }
    break;+++-+
    case 2:
    if (b==0)
    {
        i--;
        PORTD|=  (1<<i);
        b=2;
    }
    else
    {
        b=2;
    }
    break;
}
}

int main(void)
{
    setup();
    while (1) loop();
    return 0;
}

ISR(ADC_vect){

    int AC = ADC;
    if(AC < 600 && AC > 400) a = 0;
    else if (AC > 1000) a = 1;
    else if(AC < 40) a = 2;
    _delay_ms(20);
    switch(a){
        case 0:
            b=0;
            break;
        case 1:
            if (b==0)
            {
                i++;
                PORTD &= ~(1<<i);
                b=1;
            }
            else
            {
                b=1;
            }
            break;
        case 2:
            if (b==0)
            {
                i--;
                PORTD|=  (1<<i);
                b=2;
            }
            else
            {
                b=2;
            }
            break;
    }

}