SparkFun 20x4 SerLCD - RGB Backlight (Qwiic) Reviews

Add a vibrant, 24x4 Black on RGB Liquid Crystal Display to your custom electronics without the traditional wiring headache. The SparkFun SerLCD streamlines the entire process by mounting an AVR ATmega328P microcontroller directly to the back of the screen. This display completely eliminates the need for an external LCD backpack by handling all of the screen control internally. Whether you are outputting simple text, sensor numbers, or diagnostic data, this smart display simplifies your hardware footprint while offering incredible flexibility. Three Ways to Communicate To ensure this display works seamlessly across a wide variety of platforms, it supports three distinct communication protocols: Serial, I2C, and SPI. Solderless I2C: A built-in Qwiic connector brings this serial LCD directly into the Qwiic ecosystem, enabling instant, plug-and-play integration. Reliable Serial: The onboard microcontroller uses an 11.0592 MHz crystal for highly accurate serial communication, with baud rates adjustable from 1200 to 1000000 (defaulting to 9600). Smart Buffering: The display features an incoming buffer that safely stores up to 80 characters, plus an operational backspace key for easy text correction. Open-Source Firmware Customization The firmware driving this SerLCD is fully open-source and features an Arduino-compatible bootloader, allowing you to easily push updates or modify the code to fit your exact needs. Beyond the code, you have full software control over the physical display elements. Pulse width modulation (PWM) allows you to directly control the RGB backlight brightness to manage current consumption, as well as software-defined contrast adjustments. You can even program your own user-definable splash screen to display upon bootup! Please keep in mind that the SerLCD operates on 3.3V logic. If you are connecting it to a 5V microcontroller, you'll need to use a logic level converter to prevent permanent damage to the board. If you are using the on-board Qwiic connector, simply plug it into your 3.3V development board, and you will be up and running immediately.