unsigned t1 = 0, t2 = 0, start = 0;
int flag = 0, dFlag = 0;
int stepperControlPin = 12, directionPin = 11, level = 0;
int count = 0;
void setup() {
  // put your setup code here, to run once:
  pinMode(stepperControlPin,OUTPUT);
  pinMode(directionPin,OUTPUT);
  t1 = millis();
  start = millis();
  digitalWrite(directionPin,LOW); 
  Serial.begin(9600);
}

void loop() {
  if (flag == 0){
    flag = 1;
  }
  t2 = millis();
  if (t2 > (start + 4000)){
    start = t2;
    if(dFlag == 0){
      digitalWrite(directionPin,HIGH);
      dFlag = 1;
    }
    else{
      digitalWrite(directionPin,LOW); 
      dFlag = 0;
    }
  }
  if (t2 > (t1 + 8)){

    Serial.println(t2-t1);
    t1 = millis();

    if (level == 1){
      digitalWrite(stepperControlPin,HIGH);
      level = 0;
      count ++;
    }
    else{
      digitalWrite(stepperControlPin,LOW);
      level = 1;
    }
  }
}