From: "Michael Stewart" <mike AT reggin DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: putpixel method
Date: Tue, 1 Jun 1999 08:58:31 +0100
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

leroy wrote in message <37533712 DOT 2CB224D2 AT hitech DOT net DOT au>...
>Nate Eldredge wrote:
>
>> Writing to video memory is not risky per se; the risk comes if you miss
>> and write to some other kind of memory :)  In the above example, it
>> might be wise (while debugging) to check that y < 200 and x < 320, and
>> that you have the right number of zeros in 0xA0000.
>> --
>
>Isn't it 0xA000, only 3 zero's.  Thats the address I always write to and it
>works.


It is 0xa0000
In a real mode program you would access segment 0xa000 offset 0x0000, but to
convert that value to a pmode offset (?) you would do this
offset = segment * 16 + offset
Which in the above example is 0xa0000. I think this is documented in the
FAQ.

>The irony of it is pretty funny though.
>
>Cheers,
>
>leroy.