>On 2002-04-10 11:41:41, blito wrote:
>>On 2002-04-09 09:16:27, J. Weeks wrote:
>>>On 2002-04-08 14:06:08, blito wrote:
>>>hello out there
>>>i'm working on a boot sector that finds a
>>>file in a diskette. The file sistem i'm using on is
>>>Fat12 but i want to interpret also ex2f.
>>>i already have the fat12 part coded but i don't
>>>have more space in the boot sector.
>>>could you help me!!!.
>>
>>I would suggest not compressing your bootsector.
>>I would imagine it would get a little too complicated,
>>and you'd still run out of space. If you were to
>>do so, you couldn't compress the first part of the
>>boot sector, because (if you're supporting FAT)
>>you'll have to have that FAT disk info uncompressed
>>so everyone can read it, so that leaves less
>>room for your decompression routines, and the
>>standard code.
>>
>>You'd probably be best to simply use a multi-stage
>>boot routine. Have your boot sector do some
>>stuff, and then load in another block of code,
>>and jump to it. This new block of code could,
>>conceviably, be compressed, if need be. It would
>>also be the block which would load the kernel
>>(which, again, could be compressed). I wouldn't
>>reccomend trying to compress the boot sector,
>>though.
>>
>>>i'm looking for a packer or something like that.
>>>Another problem is that the Fat12 final cluster mark
>>>in my boot sector is 0xfff, not 0xff8 i have seen in all boot sector
>>>examples. i couldn't get it works with 0xff8.
>>>please help me!!!!!!.
>>
0xff8 is the value Microsoft assigns for the FAT
end-of-chain. In one of their publishings, it
was stated that other software which supports FAT12
uses different values (ranging 0x0ff8 - 0x0fff, so it
is best to check for anything equal to or greater than
0x0ff8 (after clearing the high nibble). I'd direct
you to the document I read this from, but can't
seem to find it anymore. Hope this helps.
>>Unfortunately, I can't help you on this one... I
>>don't know much about FAT. I'd suggest checking
>>out some more code, and also reread the FAT specs
>>(
www.wotsit.org has a bunch of docs of FAT).
>>
>>Jeff
>thank's jeff.
>i do not know what i have done withougth your help.
>you've been very helpfull