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

[Chuck Guzis]

On 04/17/2017 05:43 PM, Terry Stewart via cctalk wrote:
>>> It may also be that is just doesn't support 77 and can only do 80
>>> tracks.
> 
>> I don't think it is this.  I can format it fine with 77 tracks
>> using 22DSK
> and IMD.  It has no problem reading or >writing to 77 track formatted
> disks.
> 
> Oh sorry Dwight, I thought you meant the drive here.  You mean MS-DOS
> 6.22 I guess.

What Fred said.  MS-DOS's format matches the parameters against what it
knows, not what you tell it.  For instance, you can't do /n:14 /t:80.

IMD and 22Disk have their own formatters and talk to the hardware directly.

If you can find an old registered copy of FORMATQM, it allowed very
flexible formatting.   So, you could format a DMF floppy by defining a
format in the FORMATS.CFG file thus:

  DMF: LENGTH 512 SECTORS 21 CYLINDERS 80 CLUSTER 2 RESERVED 1
          FIRST 1 MEDIAB 0F0 SIDES 2 INTERLEAVE 2 SKEW 3 DIRECTORY 16

You can even define your own boot sector.

FWIW,
Chuck