Basic Arduino LCD Clock

Ever needed an extra clock? Just so happens that you have an Arduino, LCD display, a Breadboard, and some jumper wires about? This 3-step copy-and-paste instructable is great for anyone looking for a simple, useful project, or just for a cool first project or showcase of your skills.

Arduino Uno

Arduino LCD Display

Jumper Wires

400-pin [or larger] Breadboard

Arduino IDE

Chromebook, Windows, Linux, or Mac PC

Identify the pins on your LCD display:

- Most LCD displays have 16 pins arranged in two rows.

- The pinout may vary depending on the specific model, so refer to the datasheet or documentation for your LCD display.

Connect the LCD display to the Arduino:

- Connect the VCC pin of the LCD display to the 5V pin on the Arduino.

- Connect the GND pin of the LCD display to the GND pin on the Arduino.

- Connect the SDA pin of the LCD display to the SDA (A4) pin on the Arduino.

- Connect the SCL pin of the LCD display to the SCL (A5) pin on the Arduino.

- If your LCD display has a backlight, connect the positive (+) pin of the backlight to a 5-Volt pin on the Arduino and the negative (-) pin to a Grounding pin on the Arduino.

(Optional) Connect a potentiometer:

- If your LCD display does not have a built-in contrast adjustment, you can use a potentiometer to adjust the contrast.

- Connect one end of the potentiometer to the VCC pin on the LCD display.

- Connect the other end of the potentiometer to the GND pin on the LCD display.

- Connect the middle pin (wiper) of the potentiometer to the VO (contrast) pin on the LCD display.

Video Credit: DroneBot Workshop

To make sure your LCD display is working, use this basic test code in Arduino IDE.

#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library

LiquidCrystal_I2C lcd(0x27, 16, 2); // Initialize the LCD object with the I2C address and dimensions

void setup() {
  lcd.begin(16, 2); // Initialize the LCD
  lcd.print("LCD Display Test"); // Display a test message
  delay(2000); // Delay for 2 seconds
  lcd.clear(); // Clear the LCD screen
}

void loop() {
  lcd.setCursor(0, 0); // Set the cursor to the first row
  lcd.print("Hello, World!"); // Display a message on the first row
  lcd.setCursor(0, 1); // Set the cursor to the second row
  lcd.print("This is a test."); // Display a message on the second row
  delay(2000); // Delay for 2 seconds
  lcd.clear(); // Clear the LCD screen
  delay(1000); // Delay for 1 second
}

If your LCD display isn't working, go back to step one and check everything.

Now, all you have to do is code the actual clock!

In the Arduino IDE, write:

#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library

LiquidCrystal_I2C lcd(0x27, 16, 2); // Initialize the LCD object with the I2C address and dimensions

void setup() {
 lcd.begin(16, 2); // Initialize the LCD
 lcd.print("  Arduino Clock"); // Display a welcome message
}

void loop() {
 // Set the current time
 int hours = hour(12);
 int minutes = minute(0);
 int seconds = second(0);

 // Display the time on the LCD
 lcd.setCursor(0, 1); // Set the cursor to the second row
 lcd.print("Time: ");
 lcd.print(hours);
 lcd.print(":");
 if (minutes < 10) {
  lcd.print("0"); // Add leading zero if minutes is less than 10
 }
 lcd.print(minutes);
 lcd.print(":");
 if (seconds < 10) {
  lcd.print("0"); // Add leading zero if seconds is less than 10
 }
 lcd.print(seconds);

 delay(1000); // Delay for 1 second
 lcd.clear(); // Clear the LCD screen
}

Feel free to customize any aspect of this.

You've finished!