Sigmapad

Sigmapad

Sigmapad is a 9-key macropad in a 3x3 grid with an EC11 rotary encoder. It runs on QMK firmware.

It was built as part of Hack Club's Stardance and Hackpad programs to handle frequently used shortcuts and keys.

Features

• 9 Keys in a standard 3x3 grid.
• EC11 Rotary encoder (with built-in push switch) for whatever you want.
• USB-C connectivity.

CAD Model

The case consists of three printed parts: the top frame, the switch plate, and the bottom enclosure. Everything fits together using four M3x16mm screws and M3 heat-set inserts.

PCB

Here's the schematic and board layout.

Firmware

This macropad uses QMK firmware. The rotary encoder changes volume and mutes on press. The default keys are:

┌───┬───┬───┐
│ Q │ W │ E │
├───┼───┼───┤
│ A │ S │ D │
├───┼───┼───┤
│ Z │ X │ C │
└───┴───┴───┘

To flash the board, compile your .uf2 file, hold the BOOT button on the RP2040 while plugging it in, and drag the file onto the mounted drive.

BOM

Here is everything you need to build this macropad:

• 1x Seeed Studio XIAO RP2040
• 9x Cherry MX-style Switches
• 9x White Blank DSA Keycaps
• 9x Through-hole 1N4148 Diodes
• 1x EC11 Rotary Encoder
• 4x M3x16mm Screws
• 4x M3x5x4mm Heat-set Inserts
• 1x Case (Top, Plate, Bottom)

Extra stuff

Tools I used:

• CAD: Fusion
• PCB and Schematic: KiCad