[sebhc] Hard-sectored disks

bill malcolm wm65805 at hotmail.com
Fri Feb 9 10:37:30 CST 2007

Sorry the Apple II did not use soft sectored disks   -- not MFM  and does
not use  sector hole.
bill ..

----- Original Message ----- 
From: "Dave Dunfield" <dave06a at dunfield.com>
To: <sebhc at sebhc.org>
Sent: Friday, February 09, 2007 6:59 AM
Subject: Re: [sebhc] Hard-sectored disks

> > >the Apple II used 16 hole hard sectored disks.  I presume it would at
> > >be a major undertaking to get these to work on Heath hard sectored
> > >At a minimum it would seem to require a rewrite of the H17 ROM.
> >
> > It did? I always thought Apple II disks were soft sector, though the
recorded data format was
> > unusual (not FM or MFM, but rather pulse width encoding).
> The Apple-II was soft-sector, and didn't use the sector hole - that is why
you could just
> cut the WP notch and flip a diskette over without having to punch the
index hole.
> > Northstar computers used 16-hole hard sectored disks.
> No, NorthStar uses 10-sector diskettes (physically the same as H17
diskettes, although
> the actual format is different)
> Dave
> --
> dave06a (at)    Dave Dunfield
> dunfield (dot)  Firmware development services & tools: www.dunfield.com
> com             Collector of vintage computing equipment:
>                 http://www.classiccmp.org/dunfield/index.html
> --
> Delivered by the SEBHC Mailing List

Delivered by the SEBHC Mailing List

More information about the Sebhc mailing list