Corney - Corney Chocoflan and Classical Corne keyboard

Project site and firmware guide: https://projects.maxistar.me/corney/

• body remixed from this: https://www.printables.com/model/1020389-wireless-corne-chocoflan-minimal-keyboard-case

Related Projects

• Dacty: https://github.com/maxistar/dacty

Layout Helper

Use Keyboard Layout Helper to inspect and tune layers visually: https://projects.maxistar.me/keyboard_helper/

What's here

• config/: ZMK config for a split Corne on nice!nano (keymap, macros, Bluetooth bindings, west manifest).
• body/: printable/parametric case and plate models for the Chocoflan remix (scad, stl, step, 3mf).
• build.yaml: build matrix for CI (direct central, BLE halves, USB dongle, and reset firmware on nice_nano_v2).
• website/: static Astro project site and firmware selection guide. It can be built locally with cd website && npm ci && npm run check && npm run build; direct download links remain disabled until a versioned firmware release is physically accepted.
• zephyr/module.yml: declares the repo as a ZMK module, including the Corney shield root and the custom GATT features.
• docs/gatt-layer-exposition.md: UUIDs, data format, and build notes for the BLE layer characteristic.
• docs/keyboard-helper-ble-v1.md: implementation, security, queue, and build notes for the versioned Keyboard Helper event extension.
• docs/dongle-oled-verification.md: SSD1306 dongle wiring, resource delta, candidate hashes, and physical acceptance checklist.

Clone

git clone https://github.com/maxistar/corney.git
cd corney

Prerequisites

• Zephyr SDK and west already installed (ZMK setup guide)

Build firmware (locally)

1. From the repo root, pull ZMK: west init -l config && west update.
2. Build the direct topology (outputs land in build/<side>/zephyr/zmk.uf2):
   • Left (enhanced): west build -p -s zmk/app -d build/left -b nice_nano_v2 -- -DSHIELD=corney_left -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD -DCONFIG_ZMK_STUDIO=n -DCONFIG_ZMK_KEYBOARD_HELPER_EXTENSION=y
   • Right: west build -p -s zmk/app -d build/right -b nice_nano_v2 -- -DSHIELD=corney_right -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD
3. Or build the dongle topology:
   • Left peripheral: west build -p -s zmk/app -d build/left-peripheral -b nice_nano_v2 -- -DSHIELD=corney_left_peripheral -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD
   • Right peripheral: use the same corney_right command and artifact as direct mode.
   • USB dongle: west build -p -s zmk/app -d build/dongle -b nice_nano_v2 -- -DSHIELD=corney_dongle -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD -DCONFIG_ZMK_STUDIO=n -DCONFIG_ZMK_KEYBOARD_HELPER_EXTENSION=y
4. Copy the corresponding UF2 to each nice!nano over USB bootloader.

corney-left-enhanced is the single supported left-central image for direct BLE operation. It provides the ordinary keyboard HID behavior together with Keyboard Helper telemetry. Pair it with the universal corney-right image, which supports right halves both with and without the physical trackpad sensor.

The optional dongle topology uses corney-left-peripheral and the same corney-right image as two BLE peripherals. corney-usb-dongle is their keyless central and sends keyboard and pointing HID to the computer over USB. It drives a 128x64 SSD1306 status display over I2C and keeps the full Keyboard Helper GATT service available over a separate encrypted BLE connection. Both host-facing central images use the default name Corney.

ZMK Studio is intentionally disabled in the release firmware. The active layout is compiled from config/corney.keymap; change that file and rebuild the left image to edit the layout. Previously saved Studio overrides are not applied. The full Keyboard Helper event and diagnostics service remains enabled.

Build firmware with a custom Bluetooth name

The default Bluetooth device name is Corney. To override it, pass CONFIG_ZMK_KEYBOARD_NAME when building a host-facing central.

Local build examples:

• Left (enhanced): west build -p -s zmk/app -d build/left -b nice_nano_v2 -- -DSHIELD=corney_left -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD -DCONFIG_ZMK_STUDIO=n -DCONFIG_ZMK_KEYBOARD_HELPER_EXTENSION=y -DCONFIG_ZMK_KEYBOARD_NAME=\"CorneyMX\"
• USB dongle: west build -p -s zmk/app -d build/dongle -b nice_nano_v2 -- -DSHIELD=corney_dongle -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD -DCONFIG_ZMK_STUDIO=n -DCONFIG_ZMK_KEYBOARD_HELPER_EXTENSION=y -DCONFIG_ZMK_KEYBOARD_NAME=\"CorneyMX\"
• Right: west build -p -s zmk/app -d build/right -b nice_nano_v2 -- -DSHIELD=corney_right -DZMK_CONFIG=$PWD/config -DZMK_EXTRA_MODULES=$PWD

Do not apply the custom name override to either peripheral image. Only the active central is host-facing.

Cirque trackpad

Both halves support an optional Cirque Pinnacle trackpad over their own Pro Micro I2C pins. Each sensor uses address 0x2a, does not connect its data-ready (DR) signal, and replaces rather than shares the former OLED position. The same corney-left-enhanced and corney-right images support four physical arrangements: no sensor, left only, right only, or one sensor on each half.

Because DR is absent, each controller with an installed sensor reads its status every 8 ms while active. The left central consumes its local sensor directly. The right half forwards relative movement, primary tap, and wheel packets over ZMK input-split to a separate central proxy listener. Both paths produce ordinary USB or BLE HID mouse reports; Keyboard Helper remains central-owned and does not carry pointer packets.

In dongle mode, both sensors are remote. The right endpoint retains input-split register 0; the left peripheral uses register 1. The dongle has matching proxy listeners and no physical sensor or matrix of its own. Button state is tracked per proxy. Because pinned ZMK v0.3.0 does not expose the disconnected split connection's input-split identity, any split disconnect conservatively clears retained remote button state; later events from a still-connected half continue normally.

The original left installation uses invert-x. The accepted right installation is rotated 180 degrees relative to its first prototype and uses invert-y without invert-x. These settings make physical finger direction match cursor direction on each assembled half.

If either image boots without its optional sensor, initialization fails once and periodic polling is not started on that controller. Matrix scanning, split operation, and an installed sensor on the other half remain independent. The pinned ZMK baseline does not release input-split buttons automatically on disconnect, so the left firmware tracks only right-proxy button state and performs a bounded safety release when that split connection disappears. Local left buttons are not part of that disconnect state.

Continuous polling costs additional battery power on every sensor-equipped half. During system suspend the corresponding polling work stops; trackpad touch alone cannot wake that controller without DR. Wake the left sensor with a left-local key and the right sensor with a right-local key or another wake source on the same controller. The right pointing path also waits for split reconnect.

Movement, scrolling, and ordinary non-overlapping taps may be used from either sensor. The pinned ZMK input listener does not source-count a simultaneous hold of the same mouse button from two sensors, so that specific dual-button gesture is unsupported.

The explicitly named Choc printable entry points are body/Choc_Version/right_touchpad_body.scad and body/Choc_Version/right_touchpad_cover.scad; use body/Choc_Version/right_touchpad_assembly.scad to inspect controller, reset, sensor, and wiring clearances. Hardware acceptance for this topology is tracked in docs/right-peripheral-trackpad-verification.md.

USB dongle OLED

The corney-usb-dongle firmware selects one four-wire 128x64 SSD1306 module at I2C address 0x3c and displays a hybrid status screen. It preserves ZMK's standard output indicator at the upper left, local dongle battery indicator at the upper right, and active layer at the lower left. One compact row below the local battery shows both split-peripheral levels, for example 78% 56%.

The two remote values follow persistent ZMK split-slot order but deliberately have no slot numbers or left/right labels. Resetting bonds can reverse their order without changing the meaning of the pair. An unavailable, not-yet-seen, or disconnected value is shown as --; pinned ZMK v0.3.0 also uses zero as its disconnect sentinel, so a genuine remote 0% is indistinguishable and is likewise shown as unavailable. The standard dongle battery widget's power symbol reports USB presence; it does not establish that an optional dongle cell is charging.

Wire the display only to the dedicated dongle nice!nano v2:

SSD1306 pin	nice!nano v2 / Pro Micro pin
VCC	3V3
GND	GND
SDA	D2 / P0.17
SCL	D3 / P0.20

Use a 3.3 V-compatible module; do not power an unknown panel from RAW or 5 V. The firmware expects address 0x3c, 128x64 geometry, and the orientation used by the tested module. The screen normally blanks when ZMK enters idle and resumes after keyboard activity. The left and right halves do not contain this OLED node—their separate I2C buses remain available for optional Cirque sensors.

Only the dongle needs to be reflashed for this display change. If the hybrid screen prevents normal dongle operation, reflash .artifacts/show-corney-battery-levels-on-dongle/corney-usb-dongle.uf2; the two peripheral images and their split bonds do not otherwise change. Build and physical acceptance evidence is recorded in docs/dongle-hybrid-status-screen-verification.md.

CI/CD

GitHub Actions is the primary CI/CD pipeline. It runs portable protocol/metadata tests, native ZMK integration tests, and builds corney-left-enhanced, corney-left-peripheral, corney-right, corney-usb-dongle, and settings-reset firmware artifacts. A manual workflow run can override the Bluetooth name for either central image only.

The GitLab CI configuration is retained as an equivalent alternative for a future GitLab mirror. Local Bluetooth name overrides remain a CMake option so the right/peripheral image cannot accidentally receive a host-facing name.