I hope this question is in scope for this site.
While I was just about to throw away my very old internal CD Writer (PATA Interface) in E-Waste, I saw two pins on its extreme left back panel interface mentioning DIG ( D G being Pinouts) on it.
See the snapshot, the next one right to it is a 4 Pin Audio interface and next to that is Master/Slave/Cable Select pins.
Does anyone know what was this DIG? There’s absolutely no reference of it on the internet.