Aspire 9500 Insyde MobilePro BIOS lzh/lza compression used ?

itsmemario

Dear Acer, Dear community,

 

is there any chance to get any info on the compression method used on your 2005 "Acer Aspire 95000" laptop

that uses the Insyde MobilePro BIOS 4.20.10 (Acer HQD 70) ?

 

Its 512kb and should be 1MB unpacked. Unfortunately the lzh/lza(?) compression used seems to be "Acer modifed".

Any chance to forward me this to your R&D section maybe ?

 

Regards,

itsmemario

JackE

What problem are you having with this machine?

 

Jack E/NJ

itsmemario

Hi,

 

Id like to exchange the Acer Splashscreen (IMAG001) and the Intel logo (OSBLOGO) that shows up when switching the laptop on.

 

Regards,

JackE

What software are you using to try to change this? Jack E/NJ 

itsmemario

I tried to use "Insydeco" for example, to uncompress v1.30 to v1.70 with it.

It works on other MobilePRO 4.20.10 BIOS files that are 1 megabyte in size.

 

I also use "Advanced Bios Logo Reader", which works with 1 megabyte MobilePRO 4.20.10 BIOS files.

 

But the Acer BIOS from this Aspire 9500 is 512kb in size.

So it is still compressed/crypted in some way and is not recognized by "Insydeco".

 

I tried to look for file headers and used various LZSS/LZH/LZA/LZ77 decompression methods.

Nothing worked, even if the file structure looks nearly identical to other MobilePRO 4.20.10 BIOS files,

that actually can be unpacked and editet.

JackE

>>>It works on other MobilePRO 4.20.10 BIOS files that are 1 megabyte in size.>>>But >>>this Aspire 9500 is 512kb in size.>>>

 

Do you feel that both files originated from Acer? If so, why? Jack E/NJ 

itsmemario

Hi,

 

I know "Insyde" sold the MobilePRO BIOS files to Acer, hp, sony, etc, hence the similarities when looking at them with a hex editor.

 

And no, I dont feel both files originated from Acer. Never wrote that, sorry if that was a missunderstanding.

 

I only wrote that "editable" MobilePRO BIOS files are 1 megabyte in size and

"packed/crypted" BIOS files are only 512 kilobyte in size.

Hence this Acer Aspire 9500 MobilePRO BIOS needs to be unpacked/decrypted 1st, to be able to edit it.

So the question would be, how did acer compress/encrypt this file.

 

Using LZMA compression ? Or maybe LZ77 ? Or a derivative of it ? Thats what Id like to know.

Or "how to edit this acer bios" ?

 

For example Lamsystems released a laptop (LAM DL75) back in the days, that also used a COMPAL mainbaord, just like the Acer Aspire does. Lamsystems is using the same MobielPRO 4.20.10 BIOS as well and the file is also 512 kilobyte in size (packed/crypted) and does nearly look exactly the same like the aspire 9500 bios, when looking at the contents with a hexeditor.

 

So maybe other laptop manufacturers used the very same compression method on their BIOS as well.

But which one ?

JackE

>>>how did acer compress/encrypt this file.[?]>>>

 

From what you've written on this particular machine, I suspect that Insyde was more involved. Perhaps working with a 3rd party at this basic display level output. Jack E/NJ

itsmemario

You might be right here.

 

As there is only a standard contact form on the insyde site and as there is not much info about this particular BIOS, it will be hard to impossible, to recieve any usefull information form their support about compression algorythms used. Im sure about that, but I will try anyway.

 

Nice to lead such a discussion on the official acer forum,

as I wasnt expecting "inside" informatiosn anway.

 

Thank you for now and happy new year !

JackE

Good luck in your quest! It might prove to be an interesting journey in any event. And a great 2017 to you too! Jack E/NJ