Using int 13 while BSD is running

[Sergey 'DoubleF' Zaharchenko]

On Tue, 9 Mar 2004 22:12:31 -0800 
Jason Dictos <jason.dictos at yosemitetech.com> probably wrote:

> Aren't the nodes "/dev/ad[0-9] (ide) or /dev/da[0-9] (scsi/usb)" created by
> their device drivers, i.e. protected mode device drives? That would mean
> that I would have to make sure that the hardware is supported by a device
> driver, whereas if I had raw int 13 access I would be garanteed access to
> the drive the system booted from, and any other bios addressable device,
> without having to load any driver for the hardware. 
> 
> -Jason

Argh, I didn't get your point first. I thought your hardware wasn't
supported by int 13h, and you were trying to get FreeBSD drivers to
work for you in real mode...

Any real HDD's out there not supported by FreeBSD but supported by
BIOS'en?

Somewere around then Dan Nelson <dnelson at allantgroup.com> probably
replied:

> I guess it's possible, since you have to use the bios to make VESA
> video calls, and they work.  /sys/i386/isa/vesa.c has most of the stuff
> you would need.  Also see the i386_vm86() userland function; you may not
> even need to mess around inside the kernel.

That's v86 mode, not real mode. Sometimes it makes a difference. It
depends on how that particular BIOS was written.

To Jason: take care not to *write* anything to the disk via int 13h.
I still don't think I understand why you are using FreeBSD for this
specific purpose. Why if you just spend time escaping from the OS?

-- 
DoubleF
All I ask is a chance to prove that money can't make me happy.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20040310/e51727c9/attachment.bin