byte i, j;

void setup()
{
  pinMode(PINB0, INPUT_PULLUP);
  pinMode(PINB1, INPUT_PULLUP);

  pinMode(PINB2, INPUT_PULLUP); //per non lasciarlo flottante

  pinMode(PINB3, OUTPUT);
  pinMode(PINB4, OUTPUT);
  pinMode(PINB5, OUTPUT);

  digitalWrite(PINB3, LOW); //led mini rosso e mini bianco
  digitalWrite(PINB4, LOW); //led mini rosso e mini bianco

  digitalWrite(PINB5, LOW); //led max centrale

  i = 0;
  j = 0;
}

void loop()
{
  if (digitalRead(PINB0) == LOW) //led mini rosso e mini bianco
  {
    delay(400);
    i++;
    j = 0;
  }

  if (digitalRead(PINB1) == LOW) //led max centrale
  {
    delay(400);
    j++;
    i = 0;
  }

  switch (i) //led mini rosso e mini bianco
  {
    case 1:
      j = 0;
      digitalWrite(PINB5, LOW);
      digitalWrite(PINB4, LOW);
      delay(1000);

      

      if (i == 1)
      {
digitalWrite(PINB3, HIGH);
      delay(300);

        digitalWrite(PINB3, LOW);
        delay(300);
      }
      break;

    case 2:
      digitalWrite(PINB3, LOW);
      digitalWrite(PINB4, HIGH);
      delay(3000);
      break;

    case 3:
      i = 0;
      digitalWrite(PINB4, LOW);
      digitalWrite(PINB3, LOW);
      delay(3000);
      break;
  }

  switch (j) //led max centrale
  {
    case 1:
      i = 0;
      digitalWrite(PINB3, LOW);
      digitalWrite(PINB4, LOW);
      digitalWrite(PINB5, HIGH);
      delay(3000);
      break;

    case 2:
      j = 0;
      digitalWrite(PINB5, LOW);
      delay(3000);
      break;
  }
}