Arduino LCD Display Wiring

One of the first projects many people like to do with an Arduino is wiring up an LCD display and programming it. This is because LCD screens have so many applications in the real world. You can display information to the user, error and diagnostic codes, and even fun little animations. Creating a game on the LCD also a fun little project. Whether you’re just learning about the Arduino for educational reasons or have a real world project you’d like to accomplish, getting Arduino LCD display wiring and programming under your belt is a great thing to do!

Arduino LCD Display Wiring Basics

Getting the Arduino LCD display wiring project together relies on just a few simple parts. You’ll of course need an Arduino and the LCD display. You’ll also need a breadboard, some breadboard wires, and 10K potentiometer (pretty close will do in a pinch). The potentiometer is there to adjust the contrast of the screen, so you can’t skip it (though if you knew the exact contrast you wanted you could use a specific fixed resistor, making the contrast static rather than adjustable).

Arduino LCD Project Parts List

If you’re just getting started or just want a simple list of parts, we’ve provided a simple shopping list for you. Some of these may be affiliate links. If you use them it costs you nothing. We may get a small commission that helps us keep making awesome content like this!

QTY		PART/LINK
1X		Arduino Uno
1X		USB Type B Cable
1X		Solderless Breadboard
1X		Jumper Wire Kit
1X		Potentiometer Kit
1X		16×2 LCD Character Display

Note that most LCD character displays do not come with the pins soldered on. You can get them about $4 cheaper if you don’t mind soldering. The LCD display linked above is from Adafruit and comes with pre-soldered pins.

Wiring the Arduino to the LCD Display

The first step in getting the LCD character display working is to wire it up to the Arduino. This is a pretty simple wiring job, so it shouldn’t be too difficult even if its one of your first projects.

The LCD wiring might seem a little confusing at first. You’ll see three of its pins go to ground and two get +5V power. This is because the LCD, backlight, and LCD contrast can be controlled separately for more advanced projects. Other than contrast, we’ll just direct wire everything else.

16×2 LCD Character Display Pinout

To make things a little simpler to understand, you can reference the following pinout for a standard 16×2 LCD character display.

Arduino LCD Wiring Diagram

Thanks to the magic of Fritzing, one of my favorite tools for drawing wiring diagrams, you can see my wiring schematic.

Component Pinouts in Detail

If you happen to be better reading that looking at diagrams, let’s go over the pinouts in detail.

The LCD Wiring:

LCD PIN 1 to Breadboard GND
LCD PIN 2 to Breadboard +5V
LCD PIN 3 to Potentiometer VOUT
LCD PIN 4 to Arduino PIN 12
LCD PIN 5 to Breadboard GND
LCD PIN 6 to Arduino PIN 11
LCD PIN 7-10 no connection
LCD PIN 11 to Arduino PIN 5
LCD PIN 12 to Arduino PIN 4
LCD PIN 13 to Arduino PIN 3
LCD PIN 14 to Arduino PIN 2
LCD PIN 15 to Breadboard +5V
LCD PIN 16 to Breadboard GND

Potentiometer Wiring:

Potentiometer PIN VOUT to LCD PIN 3
Potentiometer +5V to Breadboard +5V
Potentiometer GND to Breadboard GND

Other Wiring:

Arduino GND to Breadboard GND
Arduino +5V to Breadboard +5V

Programming the Arduino for LCD Displays

The great news is that the Arduino IDE already includes an LCD character display control library built-in to use in your Sketches! So much of the work of programming a display is already done for you. In fact, the Arduino IDE includes some sample Sketches to play around with such as the following “Hello World!”, but we’ll change it to display The Geek Pub instead!

// include the library code:
#include &amp;amp;amp;lt;LiquidCrystal.h&amp;amp;amp;gt;
//initialise the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);

// Print a message to the LCD.
lcd.print("The Geek Pub!");
}

void loop() {
// set the cursor to column 0, line 1
lcd.setCursor(0, 1);

// print the number of seconds since reset:
lcd.print(millis() / 1000);
}

Understanding the Hello World Programming

We hope by now, you’ve decided understanding the Arduino LCD display wiring isn’t difficult, and your ready to learn the programming steps in a little more detail.

Let’s break down the sections of the Hello World (or in our case The Geek Pub!) sketch and add a little context to them!

The following line sets up our new display as an object and declares the pins we are using on the Arduino to control it. You could of course create constants and name them as we’ve done in other Sketch examples should you like more meaningful code.

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

The next bit of code defines the shape and size of our LCD character display. This is important so that the LiquidCrystal.h library knows how to write to your screen. In my case, the display is a 16 column and 2 row display (also called a 16×2) for a total of 32 characters. Be sure to change this line to match your display.

lcd.begin(16, 2);

The next line of code simply prints a string to the display. In my case “The Geek Pub!”

lcd.print("The Geek Pub!");

The last bit of code that occupies the loop function is designed to simply count forever once The Geek Pub! has been printed to the screen. lcd.SetCursor(0,1); moves the cursor to character 0, line 1. The second line lcd.print(millis() / 1000); prints the number of seconds since the code started executing (millis() returns milliseconds, so we divide that by 1000 to get seconds).

lcd.setCursor(0, 1);
lcd.print(millis() / 1000);

Arduino LCD Programming Basics

Now that you know the basics of the Hello World sketch, I am going to show you a few more basic functions you can use in your Sketch’s to make the display a little more useful.

Auto-scroll

Auto-scroll shifts text right and left.

autoscroll(); – Moves the text one space to the left whenever a new character is added.
noAutoscroll(); – Turns auto scrolling completely off.

Blink

Blink turns on and off the blinking of the cursor’s block.

noBlink(); – Turns off the blinking block.
blink(); – Turns on the blinking block.

Cursor

Cursor allows you to turn on/off the cursor underscore.

noCursor(); – Turns off the cursor’s underscore.
Cursor(); – Turns on the cursor’s underscore.

Display

Makes the display go blank, but keeps all data intact.

noDisplay(); – Blanks the display.
display(); – Restores the display.

Scroll

Automatically scroll the text both left and right.

scrollDisplayLeft(); – Will scroll one character position left.
scrollDisplayRight(); – Will scroll one character position right.

Serial Display

Displays text sent to the serial port on the LCD character display connected to the Arduino.

write(Serial.read());

Set Cursor

Moves the cursor to a specific character position: column, row. These examples are based on 16×2 display.

setCursor(0, 0); – Moves the cursor to be at the top left (first column, first row)
setCursor(15, 1); – Moves the cursor to be at the bottom right (last column, last row)

Text Direction

Changes/sets the direction character text will be displayed.

rightToLeft(); – Text to flows from the left of the cursor.
leftToRight(); – Text to flows from the right of the cursor.

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