/*  ___   ___  ___  _   _  ___   ___   ____ ___  ____  
 * / _ \ /___)/ _ \| | | |/ _ \ / _ \ / ___) _ \|    \ 
 *| |_| |___ | |_| | |_| | |_| | |_| ( (__| |_| | | | |
 * \___/(___/ \___/ \__  |\___/ \___(_)____)___/|_|_|_|
 *                  (____/    
 *  project tutorial url:http://osoyoo.com/?p=1109	 
 *	copyright osoyoo.com
 */	
int inputPin=4; // pin to read signal from sensor
 int outputPin=5; // pin to send  signal to sensor
 int ledpin=13;
 void setup()
 {
 Serial.begin(9600);
 pinMode(ledpin,OUTPUT);
 pinMode(inputPin, INPUT);
 pinMode(outputPin, OUTPUT);
 }
 void loop()

{
 digitalWrite(outputPin, LOW); 
 delayMicroseconds(2);
 digitalWrite(outputPin, HIGH);   
 delayMicroseconds(10);
 digitalWrite(outputPin, LOW);  
 int distance = pulseIn(inputPin, HIGH);  
 distance= distance/58; 
 Serial.println(distance); //print distance value in cm
 delay(50);
 if (distance >=50)
 {// light up LED if distance more than 50cm
 digitalWrite(ledpin,HIGH);
 }// turn off LED if distance less than 50cm
 else
 digitalWrite(ledpin,LOW);
 }