I'll speculate the more this USB HID Device is different from a keyboard & mouse, the more likely you will need the actual device to discover how to create your own. If your end game is to create a high-end arcade like device, it may be easier to get this USB Device and interface it with high end hardware: https://na.suzohapp.com/products/driving_controls/50-0102-08
I do have a G27 to test, so that's at least that hurdle overcome... My goal at the end is to create exactly what that product doesn't have, which is a control board that is:
- Easier to buy in low quantities
- Easier to program
- Open to modification
- Compatible with the Logitech drivers without any
work required host-side (this is important to ensure compatibility with as many games as possible - Xsim is what most people use for DIY wheels but I don't think it works with everything that Logitech's drivers do because of how it gets the data from the game)
- Possible to replace cheaply - or at least a more cheaply than the entire G27 - if you accidentally wire your custom 100W H-bridge wrong and blow the controller up or something.
As for why I want to do this, well, why not? I could go on but let's just say it's one of those projects that I just want to do because I want to, though learning enough about USB to be able to learn even more later would be great.