int trigPin=  12;
int echoPIn=11;
  int pingTravelTime;         
void setup() {
  // put your setup code here, to run once:
pinMode(trigPin,OUTPUT);
pinMode(echoPIn,INPUT);
Serial.begin(9600);
}
                           
void loop() {
 
digitalWrite(trigPin,LOW);
delayMicroseconds(10);
digitalWrite(trigPin,HIGH);
delayMicroseconds(10);
digitalWrite(trigPin,LOW);
pingTravelTime=pulseIn(echoPIn,HIGH);
delay(25);
Serial.println(pingTravelTime);
}