I've been having a very strange issue with a PC Engine Duo R
It's not a controller board issue, as it's been tested with multiple known good controllers, but all buttons on a 2 button controller are mapped to the D-pad, as in run and left are hit simultaneously, but run does not work on it's intended button, and same for the other face buttons.
The controller port also has been replaced and has proper continuity to the HuC6280, and the console itself has already been recapped, with no improvement.
My only guess is the HuC6280 is no good or bridged in some way I haven't discovered yet, though it's unlikely since the games and system run totally fine visually when started. If anyone's encountered this issue or had any ideas I'd love the help.