imp-firmware

imp stands for injectable mouse passthrough. It is a firmware for the Raspberry Pi Pico, designed to pass mouse input from one USB port (Host) to another (Device), while allowing inputs to be injected via i2c.

Creating the firmware

Prerequisites

Make sure you have the Pico SDK installed, along with the GNU arm embedded toolchain. Raspberry Pi itself recommends installing the SDK using their VSCode extension.

Download submodules

This downloads third party libraries from git

git submodule init
git submodule update

Building

mkdir build
cd build
cmake -DPICO_SDK_PATH=%USERPROFILE%\.pico-sdk\sdk\2.1.0 -DPICO_TOOLCHAIN_PATH=%USERPROFILE%\.pico-sdk\toolchain\13_3_Rel1 ..
cmake --build .