8" hard sectored floppies

From: Christian Corti <cc_at_corti-net.de>
Date: Fri Jun 4 01:10:04 2004

On Thu, 3 Jun 2004, Dwight K. Elvey wrote:
> I also believe that one can use hard sectored disk in place of
> soft sectored disk in most machines( of course formatted as soft
> sectored ).

No, you can't. Or at least with many side effects because the floppy
controller will see 33 index pulses (32 sector holes + 1 true index hole)
per revolution. When looking for a sector most FDCs abandon operation if
the sector has not been found after e.g. 5 revolutions i.e. 5 "holes" from
the diskette.

> quality. In fact, I punch a new index window in some of my
> double density 8 inch floppies and I've been using them, with
> no troubles, as single density.

It is always possible to format a DD disk to SD because the latter has a
similar bit density on the media.

> The 5-1/4 disk are a different story. Single/Double don't mix.

Of course they do. Single density refers to FM encoding, double density to
MFM (or M2FM). What you mean is SD/DD and HD don't mix because the
magnetic media as very different properties.

Christian
Received on Fri Jun 04 2004 - 01:10:04 BST