Re: C64 MMU POC

Am 08.07.19 um 15:44 schrieb Mia Magnusson:
> A good thing about the C128 MMU is that it has two sets of registers.
> One full set that sits in the general I/O area, and a smaller set that
> sits in the $FFxx range (iirc). That way you can do a limited set of
> operations even when the full register set is invisible.

An idea one could steal from the FPGASID project:

Only if you write some magic value (FPGASID: $65 and then $81) to a 
certain register the other registers are mapped in.
Otherwise the I/O area remains unchanged.

This reduces the "abnormality" of the memory mapping next to nothing.