int segmentPins[] = {2,3,4,5,6,7,8};
int CathodePin = 9;
int digit [10] = {
  B00000000,//LOW
  B01011101,//D
  B01110111,//A
  B01111111,//8
  B01100101,//4
  B01101111,//9
  B01110010,//F
  B00111111,//0
  B00000101,//1
};
void setup() {
  for (int i=0; i<7; i++){
    pinMode(segmentPins[i], OUTPUT);
  }
  pinMode(CathodePin, OUTPUT);
}

void loop() {
  for (int i=0; i<9; i++){
    displayDigit(i);
    delay(2000);
  }
}

void displayDigit(int number) {
  digitalWrite(CathodePin, LOW);
  for (int i = 0; i<7; i++){
    digitalWrite(segmentPins[i], bitRead(digit[number], i));
  }
  digitalWrite(CathodePin, HIGH);
}