English | 日本語 | 简体中文 |

KU-1255 Firmware Modifier

A simple GUI tool for customizing the firmware of the Lenovo ThinkPad Compact USB Keyboard with TrackPoint.
You can remap any key on the keyboard—for example, reassign the Ctrl key to the Fn key position in the bottom-left corner.

In addition, several advanced customization features are available:

• Multi Layers: Change key behavior when pressed together with the Mod key.
• Key Macros: Replace combinations of Ctrl, Shift, Alt, and Win keys with a single key press.
• Media Keys: Assign special functions such as volume control or media playback controls.
• TrackPoint Speed: Increase the TrackPoint acceleration beyond the limits of the official Lenovo driver.

Since all modifications are written directly to the keyboard's firmware, no system-side configuration is required. The layout remains consistent across all connected devices and operating systems.

---

📜 Compatible Models

Lenovo ThinkPad Compact USB Keyboard with TrackPoint (KU-1255)

Part Number : 0B47190, 0B47191, 0B47192, 0B47194, 0B47195, 0B47197, 0B47198, 0B47200, 0B47201, 0B47202, 0B47204, 0B47205, 0B47206, 0B47207, 0B47208, 0B47209, 0B47210, 0B47211, 0B47212, 0B47213, 0B47215, 0B47216, 0B47217, 0B47218, 0B47219, 0B47220, 0B47221, 0B47222, 0B47223, 0B47224, 0B47225

✅ System Requirements

• Currently the app only works on MS Windows, but macOS and Linux versions can be developed upon request.
• Microsoft Visual C++ Redistributable is required in MS Windows.
• Once the firmware is installed, the keyboard works on most operating systems, regardless of the one used during installation.
• Internet connection is required at the first run of the app to download the official firmware installer from Lenovo web page.

🚀 How to Download and Run

1. Download the latest version of ku1255-firmware-modifier.zip from the Releases page.
2. Extract the downloaded .zip file.
3. Launch ku1255-firmware-modifier.exe.
   • If you see a warning saying "Windows protected your PC" and "Microsoft Defender SmartScreen prevented an unrecognized app from starting", click "More info" and then select "Run anyway" to proceed.

🖥️ Interface Overview

1. Keyboard Selection
   Choose your keyboard model. For US layout, select: 0B47190 (84 keys - ANSI)

2. Language Selection
   Choose your preferred language. Select US / English for a typical US keyboard layout.

3. Main Layer
   Defines the default keymap. Click any key to change it, and select a key you want to newly map from the dropdown.

4. 2nd Layer
   Defines key behavior when used with the Mod key.

   • This layer is disabled by default because the Mod key isn’t initially mapped in the Main Layer.
   • The Mod key must be assigned in both Main and 2nd layers at the same position.

5. Macro Keys
   Create key macros consisting of combinations of Ctrl, Shift, Alt, and Win keys (up to 24 macros).

6. Media Keys
   Configure media keys such as volume control and display brightness (up to 11 functions).

7. TrackPoint Settings
   Set the trackpoint speed settings. You can fully control the relashionships between trackpoint tilt amount and cursor speed. You can also use easy preset settings. Speed 1 to 9 correspond to the 9-level speed setting in the driver control panel. OS without official driver installation will use Speed 5.

8. Other settings Other useful settings (e.g. Assign Fn-key functionality in addition to the original behavior of any selected key.)

9. Load config
   Load a previously saved keymap from a .json file.

10. Save config
    Save the current keymap to a .json file.

11. Install firmware
    Flash the current configuration to the keyboard.
    Make sure the keyboard is plugged in before proceeding.
    After installation, unplug and reconnect the keyboard to apply the changes.

🔧 Example: Swapping Fn and Ctrl Keys

1. Click Load config and open the file: example/Swap-Fn-Ctrl.json
2. Select keyboard you use in the Keyboard selection.
3. In the Main Layer, verify that the Fn and Left Ctrl keys are swapped.
   (Swapped keys will be highlighted in blue.)
4. Click Install firmware.
5. When the firmware installer launches, click Start.
6. After installation finishes, close the installer.
7. Unplug and reconnect the keyboard. The new keymap will take effect.

♻️ Firmware recovery

• Firmware can be installed into the keyboard repeatedly
• To restore your device to its factory firmware settings, use the Lenovo Official Firmware Installer.

---

Development

See https://github.com/haborite/ku1255-firmware-modifier/tree/main/dev#readme

Acknowledgements

The firmware binary analysis methodology employed in this project is based on the discussion in the following thread

• lentinj/tp-compact-keyboard#32
• https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix

The reffered table of Usage IDs and names

• https://bsakatu.net/doc/usb-hid-to-scancode/

The app is designed to be extendable to support keyboards for various languages.
Contributions to add keyboards for your own language are very welcome!