const int PinBottom = 2;
const int PinTop = 5;

const int PinDigit3 = 3;
const int PinDigit2 = 4;


void setup() 
{
  pinMode(PinTop, OUTPUT);
  pinMode(PinBottom, OUTPUT);
  pinMode(PinDigit3, OUTPUT);
  pinMode(PinDigit2, OUTPUT);

  digitalWrite(PinTop, LOW);
  digitalWrite(PinBottom, LOW);
}

int lastTime = 0;
bool top = true;

void loop() 
{
  int currentTime = millis();
  if (currentTime - lastTime > 1000)
  {
    top = !top;
    lastTime = currentTime;
  }

  // Digit 3 (right) - switch between top and bottom
  digitalWrite(PinDigit3, HIGH);

  if (top)
  {
    digitalWrite(PinTop, HIGH);
    delay(1);
    digitalWrite(PinTop, LOW);
  }
  else
  {
    digitalWrite(PinBottom, HIGH);
    delay(1);
    digitalWrite(PinBottom, LOW);    
  }
  digitalWrite(PinDigit3, LOW);


  // Digit 2 (middle) - always bottom
  digitalWrite(PinDigit2, HIGH);
  digitalWrite(PinBottom, HIGH);
  delay(1);
  digitalWrite(PinBottom, LOW);    
  digitalWrite(PinDigit2, LOW);
}