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Index > Windows > What program is used to compress amd raid option rom?

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phpdevpad



Joined: 12 Jan 2013
Posts: 37
phpdevpad
Inside amd raid option rom I have found this string -lh5- and when I decompress with zip it gives me correct raid1.bin file. However when I compress with lha.exe -a0 it gives me header $2b long the original header is $22 and the amd raid option rom cannot uncompress the file i.e when I inserted the new amd raid rom into bios it doesn't work and it gives me an operating system not found error. I have also removed some bytes from the new header to no avail. The new archive is valid and I can uncompress it with zip for example. Thanks for your help!
Post 01 Feb 2013, 19:23
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
phpdevpad,

Probably -h0 switch is what you need. Default is -h1.
Post 02 Feb 2013, 08:40
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phpdevpad



Joined: 12 Jan 2013
Posts: 37
phpdevpad
baldr wrote:
phpdevpad,

Probably -h0 switch is what you need. Default is -h1.


Yes, can you explain about -h switch? I use LHa for UNIX version 1.14i-ac20050924 (i386-pc-mingw32) but it produces totally different compression? When I use original 16-bit lha.exe with a switch it makes almost the same binary but it doesn't work either. I have compared the compressed data and it's the same? Is this original lha.exe lzss and huffman? And how does it achieve better compression? Thank you!
Post 02 Feb 2013, 08:49
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
phpdevpad,

AFAIR -h switch is about header format. Level 0 header contains minimal amount of information (name, timestamp, sizes, attributes, CRC). You may consult LHA Notes for more information.

As I know, BIOS modules are like LHA archives, but not exactly match them ('\0' appended? or was that alignment?). Anyway, it's better to use proper tools (CBROM/AMIBCP and such) to modify BIOS images.
Post 02 Feb 2013, 11:15
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phpdevpad



Joined: 12 Jan 2013
Posts: 37
phpdevpad
baldr wrote:
phpdevpad,

AFAIR -h switch is about header format. Level 0 header contains minimal amount of information (name, timestamp, sizes, attributes, CRC). You may consult LHA Notes for more information.

As I know, BIOS modules are like LHA archives, but not exactly match them ('\0' appended? or was that alignment?). Anyway, it's better to use proper tools (CBROM/AMIBCP and such) to modify BIOS images.


Can you explain about the compression? Is this lzss + huffman or can it be lzw? I'm wondering because of the 2 lha.exe? The problem is also this isn't a bios module it's inside an option rom. However I'm not sure how the option rom uncompress the data. That's why I asked about the compression algorithm.
Post 02 Feb 2013, 12:08
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
phpdevpad,

It was 8k sliding window Lempel-Ziv with static Huffman for length/distance, IIRC.
Post 02 Feb 2013, 16:23
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phpdevpad



Joined: 12 Jan 2013
Posts: 37
phpdevpad
Doesn't work. I still get load to error misc.bin and I can't find the string.
Post 02 Feb 2013, 21:17
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