BIOS Updates forum

Hello. 1.) Yes, it is true that EGCS is a compiler. It seems to be that etBIOS / etDVD / etBrowser will generally be compiled with EGCS / GCC. yeah, I think so. Quite a lot embedded appliances somehow make use of it. 3.) Does anybody know, which kind of compression will be used for etBIOS/etDVD ? C...

Hi Borg, I will incorporate it in the next update of the article. It seems to be it is the current de-facto article on BIOS code analysis . But, it will take sometime for that.

Thx for your info, I really appreciate it

I've added new section for IDA Pro. This section is an introductory material for people who struggle to use IDA Pro. Happy reading and thx goes to people that suggested me to add that section .

well, after reading Intel's System Programming Guide and some chipsets datasheet, it seems that my statement above is partly right. In addition, the SMM "handler" area can be relocated as needed, so it doesn't have to be in the "ISA" video memory area. it can relocated high in the address space, suc...

The article has been translated to Russian by my friends at rom.by. Thumbs up and good-work guys. Its accessible at RUKOVODSTVO Pinczakko K ISSLEDOVANIYU PRINTSIPOV RABOTI Award BIOS. Note that this is still the very early version and still a lot things need to be fixed.

I've been thinking about the SMM(System Management Mode) RAM (address range A_0000h - D_FFFFh) usage for a while. As per every chipset datasheet I've read, it seems that this area of RAM is "missing" or "not seen" or "inaccessible" during normal runtime (operating system already take control) to the...

I've never tried it before. I'm not sure wheter it will work or not. But perhaps, you'd better try it and tell us about the result here :D. However, there are some peculiarities in mainboard/system BIOS handling of PCI ROM between different BIOS/mainboard. Anyway, my primary purpose of placing my co...

Maybe use PCI ROM image instead (use PCI ID of some PCI device in the system). can be problematic though :(. Some (I guess most) system bios check the PCI ROM against the existence of the corresponding device in the mainboard/add-in card slot and the corresponding PCI device must implement XROMBAR(...

I ain't sure though, but it seems that some award bios doesn't properly initialize ISA roms. I have an article regarding expansion rom here and here (section Preliminary Award Bios Modification Guide). I hope that would help you

just made a minor update to the article again. CHANGE LOG ------------------- 1. ToC improved for better navigation. 2. BIOS chip addressing improved. 3. Added new sections: "Relocatable" Hardware Port explanation Expansion ROM Handling explanation 4. Better code interpretation :wink: 5. Compressed ...

Hi. ... Well, in many Asus Award BIOS files and besides the + BIOS module header checksum + (compressed) file data checksum there seems to be a third kind of checksum at the end of a/each module. Can you tell me more about this third kind of checksum? You're right about the existence of the third c...

the LZH header structure used in Award BIOS (and its variant) is explained here (scroll down a bit, and you'll see the explanation inside a table). You can compare it with "standard" LZH level-1 header explained here . As addition, in my previous reverse engineering to Award BIOS, I found that CBROM...

I have a few ideas of what to look for based on the chipset datasheets, but I need to see the code the bios uses to do it, because I definitely do not want to go around asserting random GPIO wires on the south bridge or the i/o controller chip. Detailed hardware specs have proven all but impossible...

Maman- I have been looking at your site, and the section on putting an OS on a PCI card is very interesting. Thanks Do the principles described therein have direct analogs in the ISA realm? Does it work about the same? not really, ISA doesn't have a "programmable" address space as PCI did. But, I t...

i've been starting to working on such a thing since last year, but unable to continue since I'm waaay tooo busy. For starter, you can use IDA Pro to analyze the binary, free version of IDA Pro disassembler available at : http://www.dirfile.com/ida_pro_freeware_version.htm then I've found that the co...