//ULTRASONIC SENSOR HC-SR04
const int trigPin=14;
const int echoPin=27;
//define sound speed in cm/us
#define SOUND_SPEED 0.034
#define CM_TO_INCH 0.393701
long duration;
float distanceCm;
float distanceInch;
void setup()
{
  Serial.begin(115200);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}
void loop()
{
  digitalWrite(trigPin,LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin,HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin,LOW);
  duration=pulseIn(echoPin,HIGH);
  distanceCm=duration*SOUND_SPEED/2;
  distanceInch=distanceCm*CM_TO_INCH;
  Serial.print("Distance(cm):");
  Serial.print(distanceCm);
  Serial.print("Distance(inch):");
  Serial.println(distanceInch);
  delay(1000);
}