Page 1 of 1

Setting graphics mode in ASM using the OUT function

Posted: Thu Aug 01, 2002 11:00 pm
by MattCarpenter
I realized that you cant use VESA to set the graphics mode in bochs  (which I use to test my kernel), so I was wondering how to set the video mode in ASM without interrupts (using the out function). I'm aiming to get 640x480 res. with 256 color if possible

RE:Setting graphics mode in ASM using the OUT function

Posted: Sat Aug 03, 2002 11:00 pm
by carbonBased
Use Vesa through a VM86 Task... it's easier ;)

640x480x8bpp is a non-vga mode, and therefore would require separate support for each svga chipset if you wanna go about it directly.

640x480x4bpp is a vga mode, and you can easily support this on all VGA cards.  There's information about doing this VGADOC, which you can find around the 'net.  It's not easy, though... Vesa's probably still your best bet :)

Jeff