How to use ultrasonic sensor using arduino

materials:-

• Arduino uno
• Ultrasonic Sensor
• LED
• Jumper wires
• Bredboard

Connections

Ultrasonic vcc = Arduino 5V

Ultrasonic GND= Arduino GND

Ultrasonic Trig = Arduino Digital pin 12

Ultrasonic Echo = Arduino Digital pin 11

LED (-) = Arduino GND

LED(+) = Arduino Digital pin 13

code:-

//https://mrarduinoprojects.blogspot.com

#define trigPin 12
#define echoPin 11
#define led 13 //BLUE LED


void setup() {
  Serial.begin (9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(led, OUTPUT);
}

void loop() {
  long duration, distance;
  digitalWrite(trigPin, LOW);  
  delayMicroseconds(2); 
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10); 
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration/2) / 29.1;
  if (distance < 30) { 
  digitalWrite(led,HIGH); //distance is less than 30 so BLUE LED turns on
  }
  else {
  digitalWrite(led,LOW); //distance is more than 30 so BLUE  LED turns off
 

  }
  if (distance >= 250 || distance <= 0){    //range is 100 cm for HC-SR04 sensor
    Serial.println("Out of range");
  }
  else {
    Serial.print(distance);
    Serial.println(" cm"); //in centimeters
  }
  delay(1000);
}