int servoPin = 15;
int pulseTime;
int pos = 90;
void setup()
{
  Serial.begin(9600);
  pinMode(servoPin,OUTPUT);
  pinMode(4,OUTPUT);
  
}

void loop()
{
  // pos = 45;
  // pulseTime = map(pos,0,180,500,2500);
   // digitalWrite(servoPin, HIGH);
    //delayMicroseconds(pulseTime);
   // digitalWrite(servoPin, LOW);
   // delay(20-(pulseTime/1000));
  for(pos = 0; pos <= 180; pos += 1) {
    pulseTime = map(pos,0,180,400,2500);
    //delay(5);
    Serial.println(pos);
    digitalWrite(servoPin, HIGH);
    digitalWrite(4, LOW);
    delayMicroseconds(pulseTime);
    digitalWrite(servoPin, LOW);
    digitalWrite(4, HIGH);
    delay(20-(pulseTime/1000));
  }
  for(pos = 180; pos >= 90; pos -= 1) {
    pulseTime = map(pos,0,180,400,2500);
    //delay(5);
    Serial.println(pos);
    digitalWrite(servoPin, HIGH);
    digitalWrite(4, HIGH);
    delayMicroseconds(pulseTime);
    digitalWrite(servoPin, LOW);
    digitalWrite(4, LOW);
    delay(20-(pulseTime/1000));
  }
 
}