Klein Keyboard

Klein keyboard is a 36 keys, columnar staggered, split keyboard named after Felix Klein

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Features

• Column Staggered
• Bluetooth compatible with power switch
• Seeed Studio XIAO-BLE / Pro Micro / nice!nano* / KB2040 / RP2040(boards with Pro Micro pinout) compatible
• Hotswap MX and Choc switches support
• Trackpad support with FPC cable and direct wiring
• Reversible SMD and through hole diode footprint

* nice!nano firmware not available at the moment.

Versions

Supports multiple options of micro controller and sensors.

| Features Supported | Microcontroller | Firmware available | Wired | Wireless | | ---------------------------------------- | --------------- | ------------------------------------------ | ----- | -------- | | Encoder or OLED | XIAO-BLE | Yes | | Yes | | Encoder, OLED, TouchPad, Buzzer, Haptics | Pro Micro | Yes | Yes | | | Encoder, OLED, TouchPad, Buzzer, Haptics | KB2040/RP2040 | Yes | Yes | | | Encoder and OLED | nice!nano | No (Planned) | | Yes |

Broadly divided in two types:

Wireless

• Can be made with Seeed Studio XIAO-BLE
• Supports either rotary encoder or OLED
• Battery connectors JST and THT

Wireless touchpad is currently not supported in ZMK.

Wired

• With any Pro Micro based boards
  • Can support encoders, OLED, Touchpad, Buzzer and Haptics

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Keyboard Images

PCB with both Choc and MX switches

Low Profile Choc version

MX version

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Repo Layout and Files

.
├── BOM
│   ├── BOM-3235-SEEED.csv         <- BOM
│   └── ibom.html
├── Case
│   └── *.stl                      <- Case stl Files
│   └── Prototype                  <- FreeCad project files (Not tested)
│       └── SwitchPlateFR4         <- SwitchPlate PCB files (Not tested)
├── docs
│   └── images
├── Logo
├── PCB
└── README.md

BOM

It is available in BOM directory as csv file and interactive HTML BOM

Build Guide

• Wired build guide
• Wireless build guide

Todo

• Add Build Guide
• Add Touchpad related 3D Models
• Software support for Touchpad/OLED

Firmware

• ZMK shield for Klein with rotary encoder support.
• QMK Firmware for Pro Micro with touchpad support.

Refrences

These projects inspired and helped in making Klein:

• Lily58 (Hotswap Footprints)
• Dilemma (Trackpad Mount, Design)
• KLOR (Haptics Footprints, Design)
• Claw44 (Design)