Logitech’s Driving Force Shifter is a very common piece of kit for those who enjoy racing games, as it connects to a Logitech Racing Wheel and allows the player to control their car in a more realistic fashion. However, this accessory’s DB-9 connector must be connected to a proprietary base within the racing wheel or else it fails to work. So as a way to circumvent this annoying problem, Parts Not Included’s Dave Madison created his own custom adapter, which translates the signals from the shifter into commands over a USB port on the host PC.
To begin this endeavor, Madison purchased a DB-9 connector with the rear leads exposed, and after quickly modifying them, plugged the X/Y axis wires into analog input pins and connected the binary reverse pin into a digital input pin on the Arduino Leonardo. In terms of software, this setup requires both the Arduino Joystick library and the Sim Racing library. The latter converts X/Y values into shifter positions in order to determine the current gear, while the former communicates with the host as an emulated HID device.
To read more about this project, you can visit Madison’s blog post here.