Linux onboard: RPi CM0

FreeWili2 supports an optional Raspberry Pi CM0 module that brings full headless Linux directly onboard — no separate host machine required. The CM0 enjoys a direct connection to the onboard FPGA, giving Linux software a fast, intimate path to the programmable logic fabric.

The CM0’s single USB port is handled cleverly: it connects to both the internal USB hub as a USB gadget and to the third host port, with the role software-swapped at runtime. A dedicated microSD holds the operating system, keeping the CM0’s storage independent from everything else on the board.

Linux software running on the CM0 talks to FreeWili2 just as any application would — the drivers work exactly like the Python API, so nothing special is needed. The default mode is headless, with the CM0 drawing to the screen via the WASM API. Because CM0 availability is genuinely questionable, the board is designed to work perfectly well without one; user “bring your own module” hand-soldering is also being actively studied.