#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,20,4);
int num;
const int Trigger = 3;
const int Echo = 4; 
void setup() {
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("distancia");
  Serial.begin(9600);
  pinMode(Trigger, OUTPUT);
  pinMode(Echo, INPUT);
  digitalWrite(Trigger, LOW);
}

void loop() {
  lcd.setCursor(1,1);
  long t; //Tiempo de regreso
 long d; //Distancia en centímetros
 //lcd.print(d);
  
 digitalWrite(Trigger, HIGH);
 delayMicroseconds(10); //Se envía un pulso de 10us
 digitalWrite(Trigger, LOW);


 t = pulseIn(Echo, HIGH); 
 d = t/59;
 num=d;
 Serial.println(num);
 Serial.print("ALCANZE: ");
 lcd.print(d);
 Serial.print(" cm");
 Serial.println();
 delay(200);
}