초음파센서 거리를 I2C 문자 LCD에 표시하기

#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);


int trigPin = 7;
int echoPin = 8;

long duration, distance;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  lcd.begin();
  lcd.backlight();
  lcd.print("Ultrasonic ");
}

void loop() {
  long duration, cm;
  lcd.clear();
  lcd.print("Ultrasonic ");
  digitalWrite(trigPin,LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin,HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin,LOW);
  duration = pulseIn(echoPin,HIGH);
  cm = microsecondsToCentimeters(duration);
  lcd.setCursor(5,1);
  lcd.print(cm);
  lcd.print("cm");
  delay(1000);

}

long microsecondsToCentimeters(long microseconds){
    return microseconds/29/2;
}