Connecting an LCD to the Arduino

In this instructable we’ll be looking at how to connect a parallel LCD to an Arduino. The LCD that I am using uses the common HD44780 interface.  Many LCDs have this, you can usually tell by the 16-pin interface. You only need to solder 10 of the 16 wires to use the LCD, but this will only enable you to use the 4-bit interface.

Materials:

Arduino (with USB cable)

HD44780-compatible LCD screen

10 Jumper wires

1 10k Potentiometer

Tools:

Soldering Iron

Helping Hands (optional)

Let’s get started!

Step 1: Connecting the Jumper Wires

     The first step we need to do is connect the pins to the LCD.  For those interested, you can find the datasheet here.

     I got my LCD from sparkfun, and you can buy one here.
As I mentioned before, you only need to connect 10 pins.  Solder jumpers to these wires:


Pin 1 - Ground
Pin 2 - +5V
Pin 3 - Contrast Adjustment
Pin 4 - H/L Register Select
Pin 5 - H/L Read/Write
Pin 6 - H/L Enable
Pin 11 - DB4
Pin 12 - DB5
Pin 13 - DB6
Pin 14 - DB7

As shown in the picture below:

Pin 1 to GND
Pin 2 to 5V
Pin 3 to wiper
Pin 4 to Arduino pin 12
Pin 5 to GND
Pin 6 to Arduino pin 11
Pin 11 to Arduino pin 5 
Pin 12 to pin 4
Pin 13 to pin 3
Pin 14 to pin 2

Because we will only be writing, pin 5 will be dropped to ground to show that there will be no reading.  For those who wish to use the backlight, connect LCD pin 16 to GND and LCD pin 15 to +4.2V. 

Connect one side of the pot to GND, the opposite to +5v, and the center to LCD pin 3.  Now you're in business.

Step 2: Opening the IDE

Now, you need to open up the Arduino IDE. (For those who are lost click on the icon!)  Then click File -> Examples -> LiquidCrystal -> HelloWorld.  Open the sketch and dowload it to the Arduino board.

     You can change the text if you want.

Step 3: Mission Complete

Your done!  You can substitute text for variables, or even analogRead().  In this way you can read in sensor values and such.

Thanks for reading my instructable!   Please Comment and Rate.

Comments

[Vaibhav47]

Please may I know why we are using potentiometer here? Can we replace it with resistor? If yes- how much ohms should be preferable??

[urvashij]

I am using fingerprint module r307 and LCD together. In that, I am using 2,3 digital pins of arduino for data transfer to the fingerprint.(I tried other pin configurations for this but it didn't work) But as I am connecting LCD, it also requires same 2,3 digital pins of arduino and it is not possible for me to use 2 and 3 pins of Arduino for both lcd and fingerprint sensor for data transfer. Can you please suggest an alternative to this. Can we use analog pins of arduino as digital ones and if so the how?? PLEASE HELP... Thank you!!

[shawnalfaro]

ok so i have an Epson EA-D20025AR LCD module i want to have as a display with my arduino based project. I am attempting to reuse it from a machine i got for free, but it has 14 pins instead of 16. is it still useable with an arduino?

[Djandco]

St last! someone who takes the time to give a value for the potentiometer, 10k!
Thank you :-)

[Djandco]

"At" last even!

[rockerrock121]

how do i copy the text???????

[John JoshuaR1]

is it possible to hookup the arduino and LCD without using potentiometer??

[Georgeh3]

If you know the value you need I suppose you could use a resistor.

[KhubaibK1]

yes u can by using LCD module by ardinu which is easy to use .you just attach those pins with ardino that have to be use in your program and ither advantage is that that module is fixed on ardinu completely

[Dashing Rainbow Dash]

Can I change what pins to connect the LCD to? I need pin 2 for an interrupt.

[DyanD1]

Do you know how to connect an arduino mega 2560 R3 to 4x20 LCD??

[SumithB]

no err. great

[ShauryaS3]

how to change pins as pro mini has only 10 digital pins?
please reply soon project deadline tommorow

[SelvaK3]

I like your project and I will give 5 star

[azhween]

i need a program for interfacing lcd wit arduino atmega 328 with y=mx+c logic . please help me out

[The.Deathspace]

Sir I want to know if you can change the pin initialization of the LCD and what other pins can i used to initialize it ( I'm using pin 2 as an interrupt thats why I need to reinitialize it to other pins)

[rohanjoseph]

hello...i did what was instructed on my 16*2 LCD but after running the code all it shows is black boxes...plz help!!

[Volthaus Electronics Laboratory]

Are you using the 10k Potentiometer? That is what you need to adjust the contrast so you will be able to see the text. Check connections if you are using it.

[pallaviv]

ii this is pallavi valunj i want to write code to display the robot moving left and right on display pl help me in this

[ibenkos]

Check my instructables out to uppgrade your work on a shield