The 640k "barrier" (was: Re: cctalk Digest, Vol 44, Issue 54)

[der Mouse]

>> Still, it's possible to search an app for video display buffer
>> segment loads and alter them.  Recall that many apps would work on
>> both MDA/MGA and CGA and so altered which addess that was used on
>> the fly.
> Right.  But that's assuming simplistic coding/logic.
> What if it got real real hard?

Then it's "impossible".  Consider hackery that executes the same byte
stream twice, one byte out of sync.  Or constructs the address to
access video memory at run time.  Or constructs the instruction
sequence to do so at run time.

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