#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2); // I2C address 0x27 (from DIYables LCD), 16 column and 2 rows

#define TRIG_PIN 26 // ESP32 pin GPIO26 connected to Ultrasonic Sensor's TRIG pin
#define ECHO_PIN 25 // ESP32 pin GPIO25 connected to Ultrasonic Sensor's ECHO pin

float duration_us, distance_cm;

void setup() {
  lcd.init();               // initialize the lcd
    lcd.backlight();          // open the backlight
      pinMode(TRIG_PIN, OUTPUT); // config trigger pin to output mode
        pinMode(ECHO_PIN, INPUT);  // config echo pin to input mode
        }

        void loop() {
          // generate 10-microsecond pulse to TRIG pin
            digitalWrite(TRIG_PIN, HIGH);
              delayMicroseconds(10);
                digitalWrite(TRIG_PIN, LOW);

                  // measure duration of pulse from ECHO pin
                    duration_us = pulseIn(ECHO_PIN, HIGH);

                      // calculate the distance
                        distance_cm = 0.017 * duration_us;

                          lcd.clear();
                            lcd.setCursor(0, 0); // start to print at the first row
                              lcd.print("Distance: ");
                                lcd.print(distance_cm);

                                  delay(500);
                                  }