From:	"Sérgio Vale e Pace" <space AT gold DOT com DOT br>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: VESA Bank Switching...Please Help Me!
Date:	Thu, 19 Mar 1998 23:54:57 -0300
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Richard Michael Smith escreveu:

> Dear All,
>
> This is really driving me crazy now...I am certain it cannot be that
> difficult!

Don't worry this question should be included in the great questions of the
mankind.

>
>
> I am working with VESA 1.2 and I have got the 32-bit address of the
> bank-switching function...but can I call it without crashing? No.
>

Well, you have two options, the easy one it's use the VESA bios function
(0x4f05), but you are probably saying "Oh NO! again somebody telling me to
use the function 5", and you have the hard way, you can use the DPMI
function to call real mode procedure, to be precise
"__dpmi_simulate_real_mode_procedure_retf", and call the function using this
(use the on-line manuals for more information about how exactly do this, but
it is not really dificult).

The bios method is really easier to use in real code, but in a test in the
"i'm not sure if this will work" style I find the direct method a little bit
faster. If you want to make more perfermonce tests about this I will be glad
if you let me know your results.

If you have any other questions, let me know.

Sérgio Vale e Pace

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