Low level hardware access in FreeBSD

[gerarra at tin.it]

>Hi,
>
>I am just wondering how I can access either BIOS calls, or preferably
>registers under FreeBSD?
>
>I am trying to write a simple system capable of displaying graphics on
>the screen, and I am pretty sure I can mmap the VGA memory to my
>programs address space.
>
>However, to be able to output graphics onto the screen I think I need
>to change the state of the VGA registers from text mode (I am guessing
>thats what the console driver uses) to graphical mode (of which i know
>there exist a couple) - but I think that involves programming
>registers and I dont know how to do that under FreeBSD.
>
>Also, for the FreeBSD console driver to pick the console back up once
>it finished working, would I be required to reset the VGA registers
>back to text mode?
>
>Thanks, Alex J Burke.


FreeBSD runs in protected mode (for x86 processors) so you can't access
to BIOS calls directly. You maybe need to see IN/OUT requests for VGA port.

rookie