#include <Servo.h>


const int TRIG_PIN = 9;
const int ECHO_PIN = 8;
const int servoPin = 10;

Servo servo;

void setup() {
  Serial.begin(9600);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  servo.attach(servoPin, 500, 2400);
}


float readDistanceCM() 
{
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  int duration = pulseIn(ECHO_PIN, HIGH);
  return duration * 0.034 / 2;
}


void loop() {
  float distance = readDistanceCM();
  Serial.println(distance);
  if(distance <= 100)
  {
    servo.write(90);
    delay(500);
  } else 

  {
    servo.write(0);
    delay(500);
  };

 

}