AVR-Based Serial Enabled LCDs Hookup Guide

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Introduction

Heads up! The latest versions of these LCDs have a Qwiic connector. The previous versions did not. Some of the pictures in this tutorial are from the previous version of the hardware, however because the change is rather minor, they are still relevant. The pinouts along the edge are still the same order and position (except for the left-most cluster of 4 PTH pins).


Newer versions have qwiic connector! Silk will look like "ADM1602N1".	Older versions do not have a qwiic connector. Silk will look like "ADM1602N_v2.6"

Also note! Throughout the tutorial, the name "SerLCD" will refer to the hardware. OpenLCD will refer to the firmware.

The AVR-based serial enabled LCD (a.k.a. SerLCD) is a simple and cost effective solution for adding Liquid Crystal Displays (LCDs) into your project. The PCB design on the back of the screen includes an ATmega328P that handles all of the screen control. It can accept commands via serial, I²C and SPI. The latest versions also include a Qwiic connector for solder-less single-cable connection setup. This simplifies the number of wires needed and allows your project to display all kinds of text and numbers. We offer three varieties of the AVR-based Serial Enabled LCDs:

SparkFun 16x2 SerLCD - RGB Text (Qwiic)

LCD-16397

$21.50

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SparkFun 16x2 SerLCD - RGB Backlight (Qwiic)

LCD-16396

$21.95

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SparkFun 20x4 SerLCD - RGB Backlight (Qwiic)

LCD-16398

$26.95

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The firmware is fully opensource and available for download at the GitHub repo here:

OpenLCD Firmware GitHub Repository

This allows for any customizations you may need. Uploading firmware (custom or updates), is easily done from the Arduino IDE using a Serial Basic. See firmware update instructions in the troubleshooting section of this tutorial for more info.

Also note, the example code used below is all available in the repo (along with many more examples). Before beginning this tutorial, it's a good idea to clone the repository (or download the entire repo as a zip), to grab all of the examples. But if you prefer, you can always use the "COPY CODE" button on each of the examples below.

Note that these all have identical firmware and can accept the same commands. However, you must adjust your display characters and cursor position as necessary for each model. Also note, there is a jumper on the back of each screen, and this "tells" the firmware how to correctly set the lines and columns for each screen.

Required Materials

If you are using Qwiic, then you will only need a Redboard Qwiic, a Qwiic cable, and a Micro-B USB cable for programming.

For non-qwiic setups, you may need the following materials in this wishlist. Depending on what you have, you may not need everything on this list. Add it to your cart, read through the guide, and adjust the cart as necessary.