🚀 go-pugleaf

In article <37694@cup.portal.com>, mmm@cup.portal.com (Mark Robert Thorson) writes:
> It seems to me that anyone who designs a system with a 286, 386, or 486
> with more than 1M of memory should include hardware EMS registers and mapping
> logic, unless he only plans to run Unix.  At first, I thought maybe only
> the 286 needs it, because the other chips have paging.  But then I remembered
> that all the DOS people run in real-address mode, so the paging mechanism
> is disabled.  The only way around this would be to run your DOS applications
> in virtual-8086 mode, but I don't think anybody does that, do they?

You were right the first time -- the 386 and 486 paging mechanism works
quite well for doing EMS.  Both 386^Max and QEMM provide EMS memory by
running DOS in virtual-86 mode and using the paging registers.  That's
why none of the chipsets have EMS registers.
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