Another update for the vic20. The 16K expansion can now be disabled and I added a 3K expansion. There’s no lock to prevent enabling both ram expansion but I think that doesn’t work (but I have no idea how the real hardware would have handled it).
At least unexpanded and 3K games seems to work now but I still see problems with some basic games. They just stop sometimes with a type mismatch or similar. Anyone has an idea what that could be?