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NASM Forum => Using NASM => Topic started by: nobody on May 09, 2005, 12:24:57 PM

Title: how to achive 1024x768 resolution
Post by: nobody on May 09, 2005, 12:24:57 PM

when an os is written,how can we achive 1024x768 resolution screen.why A000:0000 page dosen't support.would u pls explain any VGA/SVGA mode or interrupt.

Title: Re: how to achive 1024x768 resolution
Post by: Frank Kotler on May 10, 2005, 01:31:03 PM

Depends on your video card... and on "where you're at" in your OS. If the card is vesa compatible, and if you've got bios interrupts available, you probably want mode 105h. IIRC, you can get, depending on card, either a "banked" 64k window at A000:0000, or you can ask the card to return the address of a "linear frame buffer". If your OS is in a state where you can use 32-bit offsets, you probably want the latter (bank-switching is slower... but not all that bad)

More info from Ralf:

http://www.ctyme.com/intr/rb-0275.htm (http://www.ctyme.com/intr/rb-0275.htm)

Best,
Frank