#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 14, 5, 4, 18, 2);
#define echoPin 21 // Echo Pin
#define trigPin 15 // Trigger Pin
long duration, distance; // Duration used to calculate distance

void setup() {
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT);  // Sets the echoPin as an Input
  lcd.begin(16, 1);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH); // Reads the echoPin, returns the sound wave travel time in microseconds
  int dis = (duration / 2) / 29.1;  // Calculating the distance in centimeters
  distance= dis-2;
  lcd.setCursor(0, 1);
  lcd.print("Distance: ");
  lcd.print(distance);
  lcd.print(" cm        ");

  delay(600);
}