I've connected my Gotek USB (with HxC firmware updated to the lastest version) on my 6128 externally. It's recognized as B: and works ok like that on a couple of games I tested it with. But I've read some apps don't work from B:. I've read that if I bridge pins 11 and 12 on the ribbon, after boot, it will flip the letters (A: <-> B:) and the external will become A:. One of the jumpers on the Gotek (the one marked S1) is connected to one of those pins. But when I bridge it, it doesn't work.
Ha anyone figured this out?
If I remember correctly, the jumper in S1 is for "B" drive and in S0 is for "A" drive. Show us how the ribbon in each end is connected.