radar1.uno

#define triggerPin 7
#define echoPin 8

long duration;
int distance;

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

void loop() {
  // get distance
  getDistance();

  // show resault
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println("cm");
}

void getDistance() {
  // reset ulterasonic
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);

  // send signal
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);

  // recive signal
  duration = pulseIn(echoPin, HIGH);

  // calculate distance
  distance= duration*0.034/2;
}