/*
* Ultrasonic Sensor HC-SR04 and Arduino Tutorial
*
* by Dejan Nedelkovski,
* www.HowToMechatronics.com
* 
* edited by Alzubair Al-Shehhi
*/

#include <SoftwareSerial.h>
#define rxPin 0
#define txPin 1
// defines pins numbers
const int trigPin = 3;
const int echoPin = 2;
// defines variables
long duration;
int distance;
//declaring softwareserial
SoftwareSerial serial(rxPin, txPin);
  
void setup() {
pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
pinMode(echoPin, INPUT); // Sets the echoPin as an Input
serial.begin(9600); // Starts the serial communication
}

void loop() {
// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
// Reads the echoPin, returns the sound wave travel time in microseconds
duration = pulseIn(echoPin, HIGH);
// Calculating the distance
distance= duration*0.034/2;
// Prints the distance on the Serial Monitor
serial.print("Distance: ");
serial.println(distance);
}