Path: utzoo!mnetor!uunet!wucs1!wuphys!hpuslma!hpfcse!hpfcmp!rjn
From: rjn@hpfcmp.HP.COM (Bob Niland)
Newsgroups: comp.sys.hp
Subject: Re: How do I read Integral Discs on non-Integral machine?
Message-ID: <1260026@hpfcmp.HP.COM>
Date: 24 Mar 88 15:14:44 GMT
References: <1483@vaxb.calgary.UUCP>
Organization: Hewlett-Packard, Ft. Collins CO
Lines: 22

re: "I have some data on 3-1/2" discs from an HP Integral computer."

> Can anyone tell me whether it would be possible to read the discs
> on a Mac or PC, and, if I can, what format the Integral uses
> for its discs?

Probably not.  The IPC {Integral} discs were probably initialized in HP 256
byte sector format, double-sided, 16 sectors/track, 77 tracks per surface.
They might also be 1024 bytes/sector, 5 sectors/track.

IBM uses 512 bytes/sector, 9 sectors/track.  I doubt if an IBM drive can
read an HP format.  The stand-alone HP 9122C/D/S disc supports IBM format.
I don't know if the IPC's 3.5" disc does, but even if it did, it seems
unlikely that your discs are in that format.  At least both HP and IBM are
constant angular velocity.  With a non-trivial amount of controller-level
programming on the PC, you might be able to read an HP format disc.

As I recall, Apple uses constant linear velocity (i.e.  variable speed),
single-sided.  I suspect there is no way an Apple can read anyone else's
3.5" format.

Bob Niland   ARPA:rjn%hpfcrjn@hplabs.HP.COM   UUCP:[ihnp4|hplabs]!hpfcla!rjn