#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);  //define I2C address 0x27, 16 column and 2 rows

#define PIN_TRIG 3
#define PIN_ECHO 2

const int jarak = 20; // distance to bottom of hopper from sensor in cm
const int ketebalan = 16; // total depth of hopper in cm
int thickness; 



void setup() {
  Serial.begin(115200);
  lcd.init();
  lcd.clear();
  lcd.backlight();
  pinMode(PIN_TRIG, OUTPUT);
  pinMode(PIN_ECHO, INPUT);
}

void loop() {
  // Start a new measurement:
  digitalWrite(PIN_TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(PIN_TRIG, LOW);

  // Read the result:
  int duration = pulseIn(PIN_ECHO, HIGH);
  Serial.print("Distance in mm: ");
  Serial.println(duration / 116);
  Serial.print("Distance in inches: ");
  Serial.println(duration / 148);
  thickness = jarak - (duration / 58);
  Serial.print("Thickness (cm):");
  Serial.println(thickness);
  
  lcd.setCursor(0, 0);
  lcd.print("thickness:");
  lcd.print(thickness);
  lcd.print("mm ");

  delay(1000);
}