unsigned char odczyt(){

      DDRA = 0xF0;
    DDRB = 0xFF;
char x;

    while(1){
    PORTA = 0xFF;
    for (int i= 4 ; i<8 ; i++){
        PORTA = ~(_BV(i));
        _delay_ms(1);
        x = PINA & 0x0F;

        if(i==4){
            if(x == 0b00001110)
            if(x == 0b00001101)
            if(x == 0b00001011)
            if(x == 0b00000111)
        }
        if(i==5){
            if(x == 0b00001110)PORTB = 0x80; //1
            if(x == 0b00001101)PORTB = 0xA0; //5
            if(x == 0b00001011)PORTB = 0x90; //9
            if(x == 0b00000111)PORTB = 0xB0; //13
        }
        if(i==6){
            if(x == 0b00001110)PORTB = 0x40; //2
            if(x == 0b00001101)PORTB = 0x60; //6
            if(x == 0b00001011)PORTB = 0x50; //10
            if(x == 0b00000111)PORTB = 0x70; //14
        }
        if(i==7){
            if(x == 0b00001110)PORTB = 0xC0; //3
            if(x == 0b00001101)PORTB = 0xE0; //7
            if(x == 0b00001011)PORTB = 0xD0; //11
            if(x == 0b00000111)PORTB = 0xf0; //15
        }

    }

    }

}