Floppy disks again

From: allisonp_at_world.std.com <(allisonp_at_world.std.com)>
Date: Mon Oct 4 10:34:44 1999

> Come on, Allison, read the message before hitting the shift key. He said two

Shift in pine is next page.

> sided (embedded in the word "DSDD"). Some (Wabash?) QD disks I saw were
> labelled "96/100 tpi 77/80 track" or words to that effect.

QD was used to imply a lot of mostly marketing hype. In general it was
simple twosided media that was cetrified for both surfaces good. What
the floppy controller did to put stuff on it was an entirely different
matter.

> Eh? What about QD? Which was that? It wasn't 35 or 40 track, but 77 or 80.
> Given the Wabash label quoted above, can you confirm absolutely that the number
> of tracks was a variation in head window?

The window size was older media when did drives didn't ahve more than 35
tracks. LAter drives that had 40 tracks needed a longer window or the
head would hit it. Had nothing to do with QD as that was more tracks
fitted to the same recoring area as 40 track (the 100 tpi were very
close).

Part of all the confusion is there is a limited set of medias and a
broader set of drives (35tr, 40tr, 96tr, one sided and two sided) and
then there were the FD controllers and their capabilities plus what the
software could drive them too.

Now if we take one media, standard 300o 5.25 twosided 96/100tpi certifed
we are now talking about litterally hundreds of formats most of which are
incompatable not by any reason of media.


Allison
Received on Mon Oct 04 1999 - 10:34:44 BST