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Vesa Modes

How do you use 640x480x256 without using VESA.  If it is using VESA, would it work to switch banks on my S3 accelerrator card.  The fastest way is the way I want.
1 Solution
Using 640x480x256 without VESA is hardware-specific; that is, if it works with a videocard from one manufacturer, it's almost for sure that it won't work with a different one. That's why VESA was accepted; nowadays, all not-so-obsolete cards support it.

Specifically, 640x480x256 is mode 101h.
To switch banks, you would call int 10h function (ax=) 4F05h, with bx and dx set accordingly. There is a faster way: at the beginning of your program, call int 10h function 4F01h, which will tell you an address of VESA information buffer. There you can get a far call address to call the 4F05h function directly.

Let me know if you need further details, or if you want to make this an answer.

HTH, Joe

I have a BGI file that lets you load graphics mode in 640x480x256 resolution. (For Ansi pascal...)

Email me at PhoenixF@writeme.com and I'll send it to you and teach you how to use it.
RaidAuthor Commented:
Sorry Pheonix, I have means to access 640x480x256, but thanks for trying to answer anyway.

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RaidAuthor Commented:
And Joe_h, yes, give me further details on how to switch banks using VESA, VERY FAST bank switching and copying(bytes).  Please E-mail me COMPLETE instructions and details at this address, (and yes I am fimiliar with some assembly language).


Thank you in advance
P.S. Yes you can turn it into an answer.
See my comment below....

And, by the way, VESA BIOS calls are well-documented in the Ralf Brown's Interrupt List, available at http://www.pobox.com/~ralf/files.html.


Hi Raid. See the Grafx unit that i told you - it implements hardware accelleration of most
graphic cards and is very fast.
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