My lefty hackpad

CodePad

CodePad is a 6 key macropad with a rotary encoder, and an OLED Display made for helping me while coding. It uses QMK firmware.

Features:

• Dual layer plastic case.
• 128x32 OLED Display
• EC11 Rotary encoder for whatever you want(volume control, scrolling)
• 6 Keys

CAD Model:

Everything fits together using 4 M3 Bolts and heatset inserts. 4 for the each corner of the case.

It has 2 separate printed pieces. The base where the PCB sits, and the top cover.

<img src=assets/cad.jpg alt="Schematic" width="500"/>

Made in Fusion360.

PCB

Here's my PCB! It was made in KiCad.

Schematic <img src=assets/schematic.jpg alt="Schematic" width="300"/>

PCB <img src=assets/pcb.jpg alt="Schematic" width="300"/>

I opted for direct GPIO connections rather than a switch matrix. Given the small number of keys (6), this simplified the PCB routing and firmware configuration without sacrificing functionality.

Firmware Overview

This hackpad uses QMK firmware for everything.

• the rotary encoder changes volume. press to mute
• The 6 keys currently as copy, paste, shift select, pause and play, keyboard brightness up and down I'm planning to change it later.
• The OLED is would have a clock but I'm searching for more creative ideas for it

BOM:

Here is everything needed to make this hackpad

• 6x Cherry MX Switches
• 6x DSA Keycaps
• 4x M3x5x4 Heatset inserts
• 4x M3x16mm SHCS Bolts
• 1x 0.91" 128x32 OLED Display
• 1x EC11 Rotary Encoder
• 1x XIAO RP2040
• 1x Case (2 printed parts)

Extra stuff

Fun fact: I completed the entire end-to-end design (3D CAD, PCB schematics, and firmware programming) a day before my 19th birthday