I’m not sure if you know of the phase - but it is a controller that sends the rotational information of a real turntable to time code that is output through RCA cables. The newest update for the phase has a USB direct HID mode that sends this signal directly to serato. It doesn’t work for Traktor. It would be cool if MIXXX worked with the HID mode.
If a Phase owner is motivated and able to reverse engineer Serato’s proprietary HID protocol, sure I guess they got at least a spec from Serato to accomplish this task in a timely manner.
The scratching implementation in the current controller system may not work as well as using Phase with a timecode audio signal, but it’s worth a try.
Ideally, the engine’s scratch code only depends on an abstract interface that reports movement signals (position, velocity) independent of how they are obtained.