#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

const int trigPin = 18;
const int echoPin = 5;

#define SOUND_SPEED 0.034
#define CM_TO_INCH 0.393701

long duracion;
float distanciaCm;
float distanciaInch;

void setup() {
  Serial.begin(115200);
  lcd.init();
  lcd.clear(); 
  lcd.backlight();
  lcd.setCursor(0,0);   
  lcd.print("Detectando :) : ");
  lcd.setCursor(0,1);   
  lcd.print("HC-SR04");
  delay(5000);
  lcd.clear();
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  duracion = pulseIn(echoPin, HIGH);
  
  distanciaCm = duracion * SOUND_SPEED / 2;
  distanciaInch = distanciaCm * CM_TO_INCH;
  
  Serial.print("Distancia (cm): ");
  Serial.println(distanciaCm);
  Serial.print("Distancia (inch): ");
  Serial.println(distanciaInch);
  
  lcd.clear();
  lcd.setCursor(0,0);   
  lcd.print("Dist: " + String(distanciaCm) + " cm");
  lcd.setCursor(0,1);   
  lcd.print("Dist: " + String(distanciaInch) + " in");
  
  delay(2000);
}