DIY USB-HID With a Twist of Lime

Make a custom USB-HID keypad in the shape of a citrus fruit. This keypad features six mechanical switches for controlling media players like Spotify, iTunes, YouTube, etc. Powered by the Adafruit QT Py RP2040 and CircuitPython.

Inside the case is a NeoPixel Jewel that slowly fades in and out making the keypad illuminate. The QT Py and NeoPixel are housed in a 3D printed case with parts that snap fit together.  

Lemon, Lime and Fruits

The case and key caps can be 3D printed in different colors. Choose a color scheme that best matches your preferred flavor of fruit. Could it be an orange, a lemon, a lime or maybe a watermelon? You decide!

Kailh Mechanical Key Switches

Click, click, click... Mechanical key switches offer a tactile feeling and there's a few varieties of switch type. Choose the type that best suits your preference.

Custom Keys

One of the goals of this project was to create a unique layout for a keypad. Originally conceived as a circular keypad, the enclosure evidently turned into a fruit inspired shape. As a result, the key caps are cute little triangular pieces.

Prerequisite Guides

Take a moment to walk through the following guides:


List of parts required for this build:

Video of hand holding a QT Py PCB in their hand. An LED glows rainbow colors.
What a cutie pie! Or is it... a QT Py? This diminutive dev board comes with one of our new favorite chip, the RP2040. It's been made famous in the new
In Stock
NeoPixel Jewel - 7 x 5050 RGB LED wired to Trinket, lit up rainbow
Be the belle of the ball with the NeoPixel Jewel!  We fit seven of our tiny 5050 (5mm x 5mm) smart RGB LEDs onto a beautiful, round PCB with mounting holes and a...
In Stock
Top down view of four piles of Kailh key switches in Red, Black, Brown, and Black variations.
For crafting your very own custom keyboard, these Kailh mechanical key switches are deeee-luxe!Come in a pack of 10 switches, plenty to make a...
Out of Stock
Silicone Cover Stranded-Core Wire - 50ft 30AWG Black
Silicone-sheathing wire is super-flexible and soft, and its also strong! Able to handle up to 200°C and up to 600V, it will do when PVC covered wire wimps out. We like this wire...
In Stock
Pack of 4 Little Rubber Bumper Feet
Keep your electronics from going barefoot, give them little rubber feet! These small sticky bumpers are our favorite accessory for any electronic kit or device. They are sticky, but...
In Stock
1 x Heat Shrink
Pre-Cut Multi-Colored Heat Shrink Pack Kit
1 x Solder Wire
60/40 Rosin Core - 0.5mm/0.02" diameter - 50 grams
1 x Adjustable 60W Pen-Style Soldering Iron
120VAC USA Plug - BEST 102C
1 x Helping Third Hand
Magnifier W/Magnifying Glass Tool - MZ101

This guide was first published on Apr 26, 2021. It was last updated on Jul 21, 2024.

This page (Overview) was last updated on Mar 08, 2024.

Text editor powered by tinymce.