Old MS-DOS & WIN Software
gilcarrick at comcast.net
Wed Dec 7 10:11:52 CST 2005
> >Is XP guaranteed to map 0x000c0000 physical into c000:0
> virtual in a
> >VM86 session? Does it keep the whole ROM space mapped to
> its corresponding
> >physical addresses? It certainly has to hide the video
> RAM... I would
> >have expected it to replace the ROM with one of its own as well.
> I don't believe XP does anything more than copy the ROM into
> a bank of RAM and then map the RAM.
On Pentium systems, at least the current ones, a larger "page" is used to
map most of the kernel memory into every logical address space with a single
entry. IIRC the default mapping is 4 MB.
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