From: Greg King (gngking_at_erols.com)
Date: 2003-12-02 05:51:15
From: ncoplin@orbeng.com; at Date: Monday, December 01, 2003, 10:32 PM
>
> > From memory, it is $d3xx (or, was it $D2xx?). So, it uses what C64
> > normally mirrors the VIC to. I guess you do it quickly so no
> > accidental writes. There may be some I/O reasons, too, which the CPLD
> > addresses.
>
> There's RAM at both, but the $D2xx is supposedly reserved for use by the
> "system," and the $D3xx page is available for users.
As far as I could tell, the "system" is GEOS -- the SuperCPU driver puts
short subroutines there which control the SuperCPU's registers. I think
that the SuperCPU's ROM does not use those pages. So, both pages are
available when you are not using GEOS.
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