The instructions and wiring on this page is based off of ladyada's wonderful Character LCD wiring guide, but updated for Fritzing. 

Assembling your LCD

Some 16x2 LCDs may come assembled, meaning the header is already soldered on:

Character LCD with 16x2 characters, with header soldered on
Standard HD44780 LCDs are useful for creating standalone projects.  This product is similar to our Standard LCD 16x2 display...
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We also have some that are unassembled with an unsoldered header:

Character LCD with 16x2 characters, with header and potentiometer
Standard HD44780 LCDs are useful for creating standalone projects.16 characters wide, 2 rowsWhite text on blue backgroundConnection port is 0.1"...
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If your LCD is assembled, you can skip these next steps and proceed directly to wiring it up. Otherwise, follow along below. 

Soldering your LCD

Soldering is a very useful skill in the realm of electronics. It's the process of joining two metals together, using another piece of metal (also known as solder) between them. If you have never done this before, Bill Earl wrote an awesome visual guide entitled Adafruit Guide To Excellent Soldering which will get you off the ground, fast. If you would prefer to watch a video, Collin's Lab covers soldering, too:

The 16x2 LCD is not that hard to solder, but it does have a lot of pins. We have some advice for soldering these like a pro:

Start by plugging your 16x2 LCD and header into your breadboard. 

Then, (with a medium-level of heat, dont make your iron too hot!) start soldering Pin 1 to the header. Next solder Pin 16. This will "tack" the header to the LCD, making soldering the rest of the pins easier. 

Now, go solder all the other pins!

Messed up? Issues with your header? Soldering is very fix-able. It'll just take time. Check this guide for your mistakes, and correct them before moving on. 

Wiring Power and Backlight

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First, plug your LCD into the breadboard. Then, connect the +5V Pin to the power rail and the GND Pinto the ground rail. 

Next, connect LCD Pin 16 to the GND rail, and LCD Pin 15 to the power rail.


Do not move on until you perform a Power Check

Let's check it's power. Connect your Metro or Metro Express to power. You should see the LCD light up. Some low-cost LCDs don't come with a backlight.

If you have one with a backlight and if you don't see it lighting up, go back and check over your wiring.

Wiring the Contrast Circuit

Next, let's place the contrast potentiometer to the left of LCD Pin 16. You can place it anywhere on the breadboard you'd like, but the next CIRC has it placed to the left of LCD Pin 16

Connect one of the outer pins of the potentiometer to the power rail. Connect the other outer pin to the ground rail. It doesn't matter which goes where, the other pins are interchangeable as long as one goes to power and one goes to ground. 

The middle of the potentiometer (the wiper) connects to LCD Pin 3

LCD Pin 1 connects to the ground rail. LCD Pin 2 connects to the power rail. These pins are the logic of the LCD.

Do not move on until you see rectangles when powered on, and the potentiometer is twisted.

Before moving on, we'll perform a small test to make sure the wiring is correct. Plug in your Metro or Metro express and twist the potentiometer. You should see black rectangles appear on the first line of the LCD. If you don't see this, check your wiring before moving on.

Wiring the Data Bus

The RW Pin is not required for this guide, as we are only writing to the display. Connect LCD Pin 5 to the ground rail.

Next, we are going to connect the RS Pin. We used a blue wire to connect LCD Pin 4 to Metro Digital Pin 7

The EN Pin is next. We used a green wire to connect LCD Pin 6 to Metro Digital Pin 8

Next is the first of the data pins, DB7. We used a white wire to connect LCD Pin 14 to Metro Digital Pin 12

 DB6 is up next. We used an orange wire to connect LCD Pin 13 to Metro Digital Pin 11

Connect DB5 (we used a purple wire)from LCD Pin 12 to Metro Digital Pin 10.

Finally, we connect DB4 with a gray wire from LCD Pin 11 to Metro Digital Pin 9

Check that you have a 4-wire gap between your data pins like this:

This is what you should have on your desk, proceed to the code section after double-checking your wiring:

This guide was first published on Aug 18, 2017. It was last updated on Jul 16, 2024.

This page (Wiring) was last updated on Aug 03, 2017.

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