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What text mode does GRUB 0.97 use?

Posted: Fri Jan 01, 2010 7:55 am
by jasonc122
Hi,

What text mode does GRUB 0.97 use once it has loaded an OS image?

Thanks.

Re: What text mode does GRUB 0.97 use?

Posted: Fri Jan 01, 2010 8:25 am
by Creature
If you mean what "resolution" then I guess it would be whatever is default? AFAIK GRUB doesn't explicitely set a mode. 80x25 is what I always assume.

Re: What text mode does GRUB 0.97 use?

Posted: Fri Jan 01, 2010 10:28 am
by gravaera
Hello,

Actually, it should be fully possible to write a VGA text mode driver that is independent of the current resolution (cols x rows).

You may read the number of rows x cols for the current text mode from the BIOS Data Area, and store them into a variable in your console class. In vga_text_init() or construction, or however you do it, you read the values.

http://pagesperso-orange.fr/pierrelib/h ... _Area.html

--Good luck
gravaera

Re: What text mode does GRUB 0.97 use?

Posted: Thu Jan 07, 2010 7:24 am
by jasonc122
Thanks for your replies.

Yes Creature your suspicion is correct; GRUB 0.97 hands over control to a kernel image with an 80x25 text mode set.