How to Use an I2C LCD Display with Arduino

Introduction

Standard 16x2 LCDs require many pins. By using an I2C adapter, you can control the entire display with just two data wires (SDA and SCL).

Components Required

• Arduino Uno
• 16x2 LCD with I2C Adapter
• Jumper wires

Wiring

Install Library

Search for LiquidCrystal I2C by Frank de Brabander in the Arduino Library Manager.

The Code

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Hello, ScienIoT!");
}

void loop() {
  lcd.setCursor(0, 1);
  lcd.print("Uptime: ");
  lcd.print(millis() / 1000);
  lcd.print("s");
  delay(1000);
}

Tips

• If the screen is blank, adjust the blue potentiometer on the back of the I2C module to set the contrast.
• The default I2C address is usually 0x27 or 0x3F.