Trick to backup your bios w/o Bios Savior

Only for programmers and BIOS gurus with technical questions.
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Master Flasher
Posts: 173
Joined: Sun Mar 31, 2002 2:08 pm
Location: Taka Bonerate National Park, Indonesia

Bios Chip Hacking trick
Finally I found the trick to hack my bios safely without using the so
called Bios Savior, the trick as follows:
1. Use a bios chip (FlashROM) with the same type as the one in your current
Mobo as a backup in case something went wrong. To do so, remove any
protectors that avoid you from seeing the type of your mobo bios chip
(Usually Award or Ami logo(s)). Then identify it, in my case it's
written as follows (in the top of the chip)
Winbond W29C020C-90B
where the W prefix means built by Winbond and the xxxxxxxxxxx perhaps
is the batch number. And the bios chip type is 29C020 , in my experience
the C after W29c020 doesn't really matter and the postfix 90 need to be
concerned (it means 90 ns access time). The chip I use as a
backup chip is:
Atmel AT29C020
xxxxx 90

where the AT prefix means made by Atmel and the 29C020, and 90 means 90
ns access time.

!!!CAUTION do this first: !!!

-> Find the datasheet of the bios chip of your current mobo
-> Find the datasheet of the bios chip you're gonna use as a backup
-> Make sure both the chip compatible each other in terms of voltage
level(in my case 5 volts-only), capacity (in my case 256KB), access
time in my case 90 ns the chip cost USD 12 .

2. Do a hot flash (hot swapping), and flash the bios binary file to the
new bios chip (in my case the Atmel one). (Remember the caution above
dud ).

==> Double check chip position every time you're going to insert the bios (the pin no.1)<==
chip cause if it's wrong there's a big chance u're destroying the
chip, if it is exchanged, you are exchanging a ground pin and a voltage supply pin so the chip will be broken :(.

@@lert !!!

In this step BUG sometimes occur. As in my case, at first I use
UNIFLASH ver 1.25 (since it's mentioned in the readme file that
AT29c020 already verified with the flasher <means work fine>). But BUG
OCCUR, the flasher didn't recognize the Atmel chip. I'm aware that
the flasher have some problem with my northbridge VIA693A aka VIA
Apollo Pro 133, and that could be the cause of this BUG.

:) ---> Solution

Then I decide to use awardflash version 7.31 (the one comes with
the mobo bin file). And it works (hip hip horey.....). Finally the
bug resolved.

3. Now you get a brand new backup bios without using Bios Savior.
Kool isn't it dud ........................ :)

my system as follows:

Processor Intel(R) Celeron (tm) 300A (300 MHz @ 540 MHz)

Mobo Iwill VD133 (Award modular bios v4.51 PGNM,
VIA693A Northbridge
VIA596B Southbridge,
bios release used : July28th 2K <VD30728.bin>)

Hard drive Maxtor 2B020H1 ATA100 20GB 5400RPM

Abit Slotket III converter card VCore @ 2.3 Volts VIO @3.6 Volts

CDROM Teac CD-540E

RAM 128MB CL2 timing turbo @ 120 MHz

Video Card Powercolor Riva TNT2M64 vid card (bios already hacked)

Sound Card Addonics SV550 (Yamaha 724 chip)

Anyway remember that when flashing the bios I remove the Sound card,
and disconnect all IDE (ATAPI) connector from the mobo to prevent
any error that may damage the system. Then booting safely from the
floppy disk.
Posts: 3153
Joined: Thu Mar 21, 2002 8:16 pm
Location: Near Hannover (CEBIT) Germany

Uniflash works with the Atmel 29C010 or 29C020 Chips (proved) but has some recognition problems with them .
Use Uniflash -Chiplist to get the ID-number for the Chip and use it with Uniflash -Force xxxx .
Master Flasher
Posts: 173
Joined: Sun Mar 31, 2002 2:08 pm
Location: Taka Bonerate National Park, Indonesia

Thanks dud, I've been so hard figuring out how to use the -force option in Uniflash. :D
The UniFlasher
Posts: 3122
Joined: Wed Mar 20, 2002 4:16 pm
Location: Slovakia

Try to read documentation...
I know that no-one reads docs :D
Patched and tested BIOSes are at
UniFlash - Flash anything anywhere
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