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Index > OS Construction > Floppy's BPB

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Carlos



Joined: 16 Apr 2009
Posts: 4
Location: Chile
Carlos 19 Apr 2009, 02:36
How can I see my floppy's BPB fields?

http://en.wikipedia.org/wiki/BIOS_parameter_block
Post 19 Apr 2009, 02:36
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ManOfSteel



Joined: 02 Feb 2005
Posts: 1154
ManOfSteel 19 Apr 2009, 07:51
For a floppy, it will be on the boot sector (sector 0).

There are many disk utilities that can read and dump sectors to files (e.g. PartCopy can be found here).
Or you can use disk editors like WDe.

Or you can use BIOS's int 0x13, fct 2 to do it manually.

Note that the BPB is only used in Microsoft's file systems, AFAIK.
Post 19 Apr 2009, 07:51
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Goplat



Joined: 15 Sep 2006
Posts: 181
Goplat 19 Apr 2009, 16:11
An easy way is to just use good old "debug":
Code:
C:\>debug
-l100 0 0 1
-d
0B96:0100  EB 3C 90 4D 53 44 4F 53-35 2E 30 00 02 01 01 00   .<.MSDOS5.0.....
0B96:0110  02 E0 00 40 0B F0 09 00-12 00 02 00 00 00 00 00   ...@............
0B96:0120  00 00 00 00 00 00 29 DC-17 16 08 4E 4F 20 4E 41   ......)....NO NA
0B96:0130  4D 45 20 20 20 20 46 41-54 31 32 20 20 20 FA 33   ME    FAT12   .3
0B96:0140  C0 8E D0 BC 00 7C 16 07-BB 78 00 36 C5 37 1E 56   .....|...x.6.7.V
0B96:0150  16 53 BF 3E 7C B9 0B 00-FC F3 A4 06 1F C6 45 FE   .S.>|.........E.
0B96:0160  0F 8B 0E 18 7C 88 4D F9-89 47 02 C7 07 3E 7C FB   ....|.M..G...>|.
0B96:0170  CD 13 72 79 33 C0 39 06-13 7C 74 08 8B 0E 13 7C   ..ry3.9..|t....|    
Post 19 Apr 2009, 16:11
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Carlos



Joined: 16 Apr 2009
Posts: 4
Location: Chile
Carlos 19 Apr 2009, 22:58
WDe showed the BPB the way I want it.

Thank you both.
Post 19 Apr 2009, 22:58
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