Page 1 of 1
Switch Video Mode int PMode
Posted: Fri Feb 22, 2008 1:43 pm
by AlfaOmega08
In Real Mode, we can switch between Video Modes using INT 0x10
In protected mode there is any way to do this or have I to use VMode?
Posted: Fri Feb 22, 2008 1:47 pm
by 01000101
you have to write the drivers for the video card or standard (vga, svga, etc..).
you might want to consider switching video modes in real-mode then just writing to the buffers in pmode.
Posted: Fri Feb 22, 2008 2:20 pm
by xyzzy
If you want to use VBE, use V8086 mode to perform the mode switch or get card info.
Posted: Fri Feb 22, 2008 3:51 pm
by os.hacker64
I believe after reading these posts that I will add switching back to real mode into my kernel so that I can set vesa modes.
EDIT: Is there an interface like VGA for XGA? This sounds weird to me, but you get my point.
Posted: Fri Feb 22, 2008 9:38 pm
by Dex
I have written a demo to show how to go to realmode from pmode and back, for mode switching (in this case vesa and text mode).
See here:
http://www.dex4u.com/demos/VesaDemo.zip
Note: this demo need vesa2.
Also its possible to switch vga modes from pmode, without using BIOS
See here:
http://bos.asmhackers.net/docs/vga_without_bios/
Posted: Sun Feb 24, 2008 5:26 am
by AlfaOmega08
Thanks Dex, I will try with your docs
Posted: Sun Feb 24, 2008 5:20 pm
by os.hacker64
os.hacker64 wrote:I believe after reading these posts that I will add switching back to real mode into my kernel so that I can set vesa modes.
EDIT: Is there an interface like VGA for XGA? This sounds weird to me, but you get my point.