TMR2615F osu pad

Giris

An open source 32 key/half (64 total) analog TMR split ortholinear keyboard & 6 key macropad/dev board (hw/TMR2615F_osu_pad). Layout is similar to Keeb.io Iris with an extra column. Uses TMR2615F, 4:8 TMUX1574RSVR mux, & AT32F405. Link is UART over type-c cable.

There are 3 unique modes of operation:

• standalone
• half A --> half B --> computer
• computer A <-- half A <--> half B --> computer B
  • Giris doubles as a KVM, you can control which computer you're typing on with a programmable macro
  • Relevant power circuitry to prevent backfeeding (GROUNDS ARE STILL BONDED!!!)

Done by Human:

• hw/ — KiCad schematics and layout. TMR2615F_osu_pad is the 6-key development board the firmware is brought up on; giris is the full-size split.
• mech/ — plates and frames.

Done by LLM + Human:

• fw/ — firmware, written from scratch in C on the Artery BSP with TinyUSB. 8 kHz USB HS polling, 8 kHz inter-half link. Host tools and a WebHID configurator live in fw/tools/.

Schematics and photos

PDFs:

• osu pad dev board (built and running, pictured above): schematic · PCB layers
• Giris split (in layout): schematic
• More photos and video of built boards: docs/photos/

The schematic PDFs draw the per-key sheet once and list each key's designators at the end; regenerate them with hw/tools/sch_pdf.py.

Setup

This repo uses git submodules for its shared footprint/3D-model library (hw/library) and hw/marbastlib. The 3D bodies will not appear in KiCad's 3D viewer unless the submodules are checked out; .step files live in hw/library/packages3d/.

Clone with submodules:

git clone --recurse-submodules https://github.com/dubnubdubnub/Giris.git

If you already cloned without --recurse-submodules, initialize them after the fact:

git submodule update --init --recursive

Note: hw/marbastlib may print an error while recursing into a nested .history submodule. That is harmless — it is upstream and holds no 3D models the boards need.

3D models

Footprint 3D bodies resolve from three locations:

• ${KICAD10_3DMODEL_DIR}/… — the standard models shipped with KiCad.
• ${KIPRJMOD}/../library/packages3d/… — this repo's hw/library submodule (must be checked out; see Setup).

When adding new 3D models to a board, reference them with one of the path variables above rather than a bare relative path (e.g. ../../packages3d/…), so they resolve regardless of where the repo is cloned.

Licence

Giris uses two licences:

Both are permissive: use it, change it, build it, sell it, no obligation to publish your changes. Apache-2.0 additionally carries an explicit patent grant. CERN-OHL-P is the hardware equivalent — software licences are written about copying source, not about manufacturing a board.

New source files should carry an SPDX header:

/* SPDX-License-Identifier: Apache-2.0
 * Copyright 2026 Isaac Chiu
 */

Third-party code

THIRD_PARTY.md is the full inventory; NOTICE carries the attributions that must accompany a distributed binary.

The short version: TinyUSB (MIT) and the ArteryTek BSP are fetched at build time by fw/tools/fetch-deps.sh and are not in this repository, though both are linked into firmware binaries. Three Artery-derived files are committed — the startup file, the linker script and at32f402_405_conf.h — and keep Artery's notice rather than Giris'. Note that Artery ships two licence statements that disagree; THIRD_PARTY.md explains which one to rely on.

Why the firmware is not GPL

Giris is written from scratch. libhmk, minipad, DeskHop and the VIA app are GPL-3.0; QMK, vial-qmk and Keychron's fork are GPL-2.0. All were read as references and no source file was ever pasted out of any of them. That is a deliberate, ongoing constraint, not an accident — copying so much as a descriptor struct would make this firmware copyleft.

This matters most for the USB XUSB (Xbox controller) interface, where both reference implementations — libhmk and Keychron's QMK fork — are copyleft. Write it from Microsoft's own specification instead:

[MS-XUSBI] — Xbox Universal Serial Bus Protocol (XUSB) Interface Extension https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-xusbi/c79474e7-3968-43d1-8d2f-175d47bef43e

It gives the class triple and the 20-byte report normatively, and its Open Specifications notice explicitly permits copying the documentation in order to build implementations of it. THIRD_PARTY.md records the limits of that permission — notably that no patent grant is established.