Re: Extracting files off “unknown” 8 inch disks. Any thoughts…

Fred Cisin cisin at
Mon Apr 17 23:20:01 CDT 2017

On Mon, 17 Apr 2017, Chuck Guzis via cctalk wrote:
> WinNT/2K/XP will read Japanese PC98 MS-DOS 1024*8*2*77, but I don't know
> if it'll format that particular format (never tried).

Doubtful on FORMAT, since that is working from a very short list of 
choices, but reading (and hence writing) can be based on what it knows or 
finds out about the disk.
Well, FORMAT.EXE on a PC98 machine would certainly know how to do it.

Is track 0 sector 1, formatted as 512BPS?
If not, how does it even come up with the idea to try 1024BPS?
(in order to read it, to find out that it should try it for reading it...)

(at location 0Bh in the BIOS Parameter Block, is the bytes per sector, but 
unless that sector is 512BPS, how did the OS read it to know to use that?)
BPB doesn't include the number of tracks, but it does have the sectors per 
track, heads, and total number of sectors.  It also has the "Media 
Descriptor Byte", but I wouldn't rely too much on that.)

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