From: Greg King (gngking_at_erols.com)
Date: 2003-12-02 05:51:15
From: firstname.lastname@example.org; 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. Message was sent through the cbm-hackers mailing list
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