Polymorphic System88 disk
cclist at sydex.com
Tue Apr 8 13:06:11 CDT 2008
> Date: Tue, 8 Apr 2008 05:59:37 -0700
> From: dwight elvey
Will all respect for your efforts, Dwight, at least you knew the
origin of the diskette and had a faint idea of what might be on them.
You haven't lived until someone shoots you a bunch of diskettes with
everything being unknown--the modulation technique, the code
representation, the data rate or track spacing or byte width, much
less the file system.
Your Polymorphics floppies sound a lot like a bunch of diskettes I
got in recently from a manufacturer's in-house PCB stuffing robot.
The format appears to be a "roll your own".
It's hard to say which is the most fun--diskettes discovered to be
GCR where you have no idea of what the group size is, nor what the
groups correspond to. Or diskettes written on something like a
typewriter where the code's not ASCII, nor does A immediately precede
B--and you have nothing that says "this is a printout of what's on
Hint: You start with a statistical analysis of the pulse stream and
go from there.
For me, it's a lot of fun, ferreting out things by bits and pieces
until the big picture emerges.
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