//Define pins for ultrasonic sensor
#define trig 7
#define echo 6

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600); //set the baud rate of serial communication to 9600
pinMode(trig, OUTPUT); //trig will have output pulses
pinMode(echo, INPUT); //echo will input pulses
}

void loop() {
  // Duration will be the input pulse and distance will be the distance to the obstacle in centimetres
  int duration, distance;
  digitalWrite(trig, HIGH);
  delay(1);//Output pulse with 1ms width on trig
  digitalWrite(trig, LOW);
  //Measure the pulse input in echo pin
  duration=pulseIn(echo, HIGH);//blocks the program to ewait for the echo to go HIGH
  //Distance is half the duration multilplied by 0.342 cm/μs
 distance=(duration*0.0343/2);
  //waiting 60 ms
  delay (60);
  Serial.print("Distance :");
  Serial.print (distance);
  Serial.println("cm");
  
}