Ping Sensor

#define trigPin 12
#define echoPin 11
#define MAX_DISTANCE 200
// define the timeOut according the maximum range. time out= 2*MAX_DISTANCE /100 /340 *1000000 = MAX_DISTANCE*58.8
float timeOut = MAX_DISTANCE * 60;
int soundVelocity = 340;
void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  Serial.begin(9600);
}
void loop() {
  delay(100);
  Serial.print("Ping: ");
  Serial.print(getSonar());
  Serial.println("cm");
}
float getSonar() {
  unsigned long pingTime;
  float distance;
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  pingTime = pulseIn(echoPin, HIGH, timeOut);
  distance = (float)pingTime * soundVelocity / 2 / 10000;
  return distance;
}