const int N = 25; // number of mirrors
int delayTime = 200; // delay time per update
const int mPins[N] = {4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28};

void setup() {

  for (int p = 0; p < N; p++) {
    pinMode(mPins[p], OUTPUT);
  }
  //Serial.begin(9600);

}

void loop() {

  for (int i=0; i < 25; i++) {

    digitalWrite(mPins[i], HIGH); // set this mirror back to low
    delay(delayTime);
    digitalWrite(mPins[i], LOW); // set this mirror back to low
    delay(delayTime);
    //Serial.println(mPins[i]);
    

  }
  delayTime = delayTime - 20;
  if(delayTime<50){
    delayTime = 200;
  }

}