Exracting a bios .rom from a Toshiba bios update

Only for programmers and BIOS gurus with technical questions.
Post Reply
Skippi
New visitors - please read the rules.
Posts: 1
Joined: Mon Apr 02, 2018 12:00 am

Mon Apr 02, 2018 12:40 am

Dear reader,
I have been experiencing some BIOS problems with my laptop since I had bought it 5 years ago. Some of these problems include: grub not appearing unless windows is HIBERNATED. Veracrypt not being able to show a decryption password on boot. Only 20% of live USB’s work. And the problems go on. I have fully erased the SSD ( dd if=/dev/zero ) and these problems still remain.
I have determined that this is most likely a BIOS problem, and I just have a buggy BIOS, and I would like to attempt to debug it.
I have downloaded and extracted the .exe from Toshiba’s website and I have found the BIOS resides in a file called BIO0089T.COM (find here )
However, looking at the hexcode, this looks like no executable that I have ever seen (far too much entropy, but still strings of 0xffffffff (so not ecrypted or compressed, but still has too much to be normal).
So the juicy question: how do I either further extract (decompress / decrypt / etc ) it, or is this the BIOS itself and I am just dumb?
Laptop: Toshiba KIRABOOK PSU7FA-00U00K
edwin
The Hardware Archivist
Posts: 6227
Joined: Wed Mar 20, 2002 7:11 pm
Location: Netherlands
Contact:

Mon Dec 17, 2018 2:30 pm

I see a newer bios was released after your post (at 30 oct 2018).
https://support.toshiba.com/support/mod ... 83&osId=26

However I'm not enirely sure this will fix all of your issues since Toshiba has decided to NOT support anything but Windows on these machines.
edwin/evasive

Do not assume anything

System error, strike any user to continue...
Post Reply