This repository provides a complete firmware solution for building a DIY force feedback (FFB) steering wheel for sim racing, targeting Arduino Leonardo/Micro/ProMicro (ATmega32U4). The firmware implements a custom USB HID joystick with full FFB support (constant, ramp, spring, damper, inertia, friction, periodic effects) and runs a 500 Hz control loop. It supports multiple hardware configurations: optical or magnetic encoders, PWM or DAC motor output, load cell pedals, button matrices, shift registers, and more. The codebase is a heavily modified fork of the BRWheel project, with custom Arduino core modifications to enable FFB HID descriptors. The repository includes precompiled HEX files for dozens of hardware variant combinations, wiring diagrams, and a serial configuration interface. While functionally complete and actively maintained, the code exhibits high technical drift due to reliance on Arduino IDE 1.8.5 and manual core patching, and the monolithic structure with extensive conditional compilation makes maintenance and reuse challenging.