[plug] Sector editing

[Anthony J. Breeds-Taurima]

On 17 Oct 2001, Garry wrote:

> I've got a Toshiba laptop for which I've lost the bios password.. Have
> found a cure, need to make a boot disk with 5 (specific) hex numbers at
> the start of the second sector...
>
> Have had a play with khexedit, but it wants to edit files, not down to
> sector level on a disk.
>
> Do I need to do something really tricky - like create a disk within a
> file, edit that then dd it to the disk, or is there an easier way?
>
> Have had a look at the docs for khexedit, but no mention of this stuff.
>
> Thought of using the dd command and skip=512, to miss the first (or
> boot) sector, but this is pretty ugly.

If thoery you _should_ be able to:

insert and format disk. (under windows if needed)
under Linux
# dd if=/dev/fd0 of=/tmp/disk.img            (copys raw disk layout to a file)
Use Khexedit to make the changes to /tmp/disk.img
# dd if=/tmp/disk.img of=/dev/fd0            (puts it back)

That should do what you need.

I found that I couldn't make that disk work.  After much 'net searching (by
many people) we eventually found and built a parralelle port device that
resets the BIOS to factory defaults.  If you can't make the disk work then
contact me off list and I'll see what we can do about getting it togetther
with your machine :)

Yours Tony.

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