Dactyl Manuform: Handwired Ergonomic Split Keyboard

Hardware project: rebuilding a Dactyl Manuform keyboard — split, ergonomic, handwired — from the keymap reverse-engineering phase through to flashing QMK firmware. The repository is tracked as a setup because it’s part of an ergonomic workstation, not a product meant to be published.

Why the Dactyl Manuform

The Dactyl Manuform is a curved variant of the original Dactyl: a 3D-printed case with key contours that follow finger length, plus a thumb cluster angled toward the thumb.

Ergonomic benefits:

• Wrists don’t have to rotate.
• Fingers travel shorter distances.
• The load is absorbed by the large muscles of the hand, not the small tendons in the palm.

The trade-off is clear: no vendor sells this unit pre-made — everything has to be handwired, and the firmware is custom.

Specifications

Hardware & Firmware

Item	Detail
Layout	Dactyl Manuform (ergonomic split)
MCU	Pro Micro (ATmega32U4) × 2
Firmware	QMK
Split connection	TRRS cable
Matrix	6×6 + thumb cluster per side
Diode direction	COL2ROW (not yet confirmed)
Master side	Right (MASTER_RIGHT)

Matrix Capacity

Theoretical maximum key count with this configuration:

$$K_{\text{total}} = 2 \times (6 \times 6) = 72$$

In practice it’s fewer — not every matrix point is used, and some are allocated to the thumb cluster, which is mapped to the same rows/columns.

Reconstruction Plan (7 Phases)

The project is organized as a phased rebuild. Each phase produces a verifiable output before moving on to the next:

• Phase 1 — Reverse-engineer the keymap from the old firmware (manual key testing)
• Phase 2 — Scaffold the QMK project structure
• Phase 3 — Configuration files (config.h, info.json)
• Phase 4 — Keymap template (keymap.c with all layers)
• Phase 5 — Confirm the master method (MASTER_RIGHT vs EE_HANDS)
• Phase 6 — Safe flashing (compile → flash → repeat for the other side)
• Phase 7 — Matrix debugging via qmk console

⚠️ The QMK files are currently placeholders. Pin assignments and matrix size have to be confirmed once Phase 1 is physically complete — get it wrong and key events won’t register at all, or will register at the wrong position.

Repository Structure

.
├── docs/
│   ├── reconstruction_plan.md   # Rencana rekonstruksi firmware
│   ├── build_log.md             # Catatan progress
│   └── images/
├── firmware/
│   └── qmk/
│       └── dactyl_manuform_custom/
│           ├── config.h                    # ⚠️ pin placeholder
│           ├── info.json
│           ├── rules.mk
│           ├── dactyl_manuform_custom.h    # macro LAYOUT
│           ├── dactyl_manuform_custom.c
│           └── keymaps/
│               └── default/
│                   ├── keymap.c            # 4 layer
│                   ├── config.h
│                   └── rules.mk
├── LICENSE
└── README.md

Build & Flash

QMK Setup

One-time install of QMK via pip:

pip install qmk
qmk setup

Compile & Flash

Copy the keyboard folder into the QMK firmware directory, then compile and flash:

cp -r firmware/qmk/dactyl_manuform_custom \
      ~/qmk_firmware/keyboards/handwired/

qmk compile -kb handwired/dactyl_manuform_custom -km default
qmk flash   -kb handwired/dactyl_manuform_custom -km default

Flashing is done per side: plug in the side you want to flash, press the reset button when prompted, then repeat for the other side.

Tools

Tool	Purpose
Neovim	Primary editor
tmux	Terminal multiplexer
QMK CLI	Build & flash firmware
Pro Micro (ATmega32U4) × 2	Microcontroller per side

References

Resource	Link
QMK Documentation	https://docs.qmk.fm
QMK Split Keyboard	https://docs.qmk.fm/#/feature_split_keyboard
Pro Micro Pinout	https://learn.sparkfun.com/tutorials/pro-micro—fio-v3-hookup-guide
Dactyl Manuform QMK	https://github.com/qmk/qmk_firmware/tree/master/keyboards/handwired/dactyl_manuform
Keyboard Tester	https://www.keyboardtester.com

Status

This project is in-progress. Progress updates are tracked in docs/build_log.md in the repo. Once Phase 1 is finished and the matrix pins are confirmed, this post will be updated with the final keymap and the custom layers used day-to-day.