Input Cover Controller
The Input Cover Controller is an RP2040-based board by CRImier (Arya) that lets you reuse a Framework input cover (palmrest with keyboard and touchpad) as a standalone USB device. It connects to the keyboard matrix, touchpad, power button, fingerprint sensor, and LEDs — turning a spare input cover into a fully functional USB keyboard12.
Design
The board connects to the input cover's FPC connector and exposes it over USB-C. It includes an optional USB hub (SL2.1) for the fingerprint sensor and adds two extra USB ports. All input connector pins are connected, with a 595 shift register driving the Caps Lock and fingerprint RGB LEDs. QMK firmware and MicroPython test code are available2. A revised v2 of the board updated the design to KiCad 7, fixed the transistor footprint (C and E were swapped), thickened 5V traces, and prepared files for PCBA production2. The assembled board is sold by FairywrenTech (Latvia) on Tindie for $203.
The Framework 13's touchpad uses a Pixart PCT3854QR controller chip with no public datasheet, communicating via HID-over-I2C. As of 2024 the touchpad was not yet supported in the QMK firmware — the keyboard, backlight, power button, and fingerprint sensor all work, but touchpad support remains a work in progress34.
| Specification | Details |
|---|---|
| Creator | CRImier (Arya) |
| MCU | RP2040 (4 MB flash) |
| USB Hub | SL2.1 (optional) |
| Firmware | QMK, MicroPython |
| Touchpad | Not yet supported (Pixart PCT3854QR, no datasheet) |
| Purchase | Tindie (FairywrenTech) |
| Source | GitHub |