Dreaded <target device ID 3FFF> - SOLVED

[Demon]

No kidding.

There's a serious short-circuit happening in those header terminals. I think the cable isn't perfectly aligned at the ends, and the contacts rubbed alongside two wires.

I tested the one I made and it's all one-pin-to-one-pin, same as with the ridiculously short cable I got with the U2 Serial programmer (when I first started), as expected from a flat header cable assembly.

I'm gonna open it up later just to look inside. I'm just happy I finally tracked the the source of ONE of my "recent" puzzles.

Robert