Does anyone around here have experience with Compaq BIOS?
I want to change the big red compaq logo that appears during the POST.
I have read some things about Award BIOS and EPA images but none of it seems to apply to Compaq. As a matter of fact I don't even know what make BIOS it is(probably Compaq's own)...
My questions are:
Is it possible to change that logo trough bios-flash or is it burnt onto some other ROM on the mobo?
I downloaded a network-flash softpaq which contained a 512kB rom image. The image only contains english frases but the setup offers more languages. Is it possible that my Compaq(deskpro EX) has some bios info on disk? (I formatted my hdd several times without losing BIOS functionality so i think not)
Hope some looked into this before otherwise gonna find it out myself. In a few weeks my vacation starts so time is on my side....

Hullo,


As the BIOS is executed FIRST, there is no effective way to disassemble it (its not an EXE or something)

Therefore do this:

1) Understand what BIOS it is (including the type and version number)

2) Search on GOOLE for BIOS dumping/backup utilities (Compaq may offer one, on their CDs)

3) Open the dump file in IDA (no disassembler comes close to disassembling BIOS dumps)

4) If not, you have to search GOOGLE for BIOS-dump Disassemblers or Simulators (that will read in your bios settings and carry on forward)

However, a before reversing BIOS, you need to have a Strong FUNDAMENTAL understanding of HOW a BIOS works, what the BIOS provides and how it is coded.

To do so (for a ready made BIOS, with SOURCE CODE), try downloading: BOCHS software (similar to simulator like VMWare, but Opensource, free and soft.) I forget the exact site, but lkely you'll get it on Sourceforge. Or simply search Google. NOTE: DO NOT SEARCH FOR "BOCSH". SEARCH FOR "BOCHS". Else you will get a lot of Drilling hardware

Understand from the source as to HOW a BIOS is made. This will help you in disassembling the BIOS dumps.

And if nothing works, you have to get D-I-R-T-Y!!! Yup, HEXEDIT the dump. Sorry, when its BIOSes, there is no EASY way.

Have Phun Forever,

I'm not sureabout newer version of the Compaq BIOS but I know for a fact that they used to have a hidden partition in the beginning of the harddrive that was used in th BIOS setup... check if they're still doing it in partition magic or fdisk or something

I'm pretty sure this is definitely BIOS info. I used to work on Compaqs everyday, and in the BIOS you could actually turn off that *boring* screen..so no doubt its part of the BIOS's nice fancy boot up routine, spitting some data out to the video card.

I'd go with the first option, trying to dump it. The the only real thing you'd have to find is a utility to burn it back in once you've modded it.

-nt20

Thnx for the hints.
I'll try to dump the f*cker and dissasemble it.
Will post if any result.

Ok, I used a Rompaq to create a bootable floppy containing the flash image and program.

Using Compaq's NET-flash tools i managed to extract the true image out of the disk (flshlite /D parrot00.204 image.bin)
And am I lucky... Browsing the image and ... At offset 0x10000 there is something that looks like a windows .bmp file!

Extracted it, signature was not "BM" but "B?" -> changed and it ... opens OK with mspaint! It's that freaking compaq logo!
Now I changed it a bit, changed the signature back, pasted it in the image and recreated the 'Parrot' - file.

Then looked a bit for a checksum(anyone knows how this is generally calculated? I did some adding of all bytes, and hoped for the checkum to be the last 2 bytes of image but no luck.)
Didn't find much and decided just to flash it as it is now.(gotta live on the edge U know)

Flashing went ok, and ... it boots!

Switch the logo on and what do I see... still the original logo!

Sh*t! Don't know what went wrong, maybe the logo is read-only(like the BootBlock), maybe the flasher did some checksumming (altough it reported no errors), maybe I must 'up' the version number on the image 2.04>2.05 maybe who knows...

Another strange thing: the flashdisk reports all OK, it even reports that a backup of the original rom is made to floppy, but there is NO backup on the floppy and the backup-ing takes less than a 0.5 second. (Bit short for 512kB to be written)

Pls send any comments for I really want to get rid of that freaking logo. Not by switching it off of but making it my own!

Later,
Brt

ummm you probably did this and i'm stating the obvious but did you change the 'M' in 'BM' back to '?' actually don't vene know if it would work... might be worth a try..

Sure did change the Bitmap Signature back to what it was.
btw. I said B? but actually the second byte is some non-ascii byte.

Thanx anyhows; The obvious things are what you forget first

I have a compaq bios , it is rom image. 256K

the processor is wrongly recognized, amd gives instructions as to what needs to be done for correct recognition and L2 cache enablement,

but compaq is not doing it , is there anyway like a editor which can edit this ROM file to put in the correct values.

Award has modbin , but this is a phoenix notebios.

or should it be done in asm.

thanks

Hi guyz,

I happen to have the URL in my bookmark, here it is
http://bochs.sourceforge.net/getcurrent.html

(Talking about emulators, does anyone know what happened to www.plex86.org? I just can't seem to open the site....)

Cheers,

Azathioprine.