Path: utzoo!attcan!uunet!cbmvax!rutgers!apple!keith
From: keith@Apple.COM (Keith Rollin)
Newsgroups: comp.sys.apple
Subject: Re: 800K disk formatting
Message-ID: <18008@apple.Apple.COM>
Date: 30 Sep 88 16:16:40 GMT
References: <8809291720.aa01487@SMOKE.BRL.MIL>
Reply-To: keith@apple.com.UUCP (Keith Rollin)
Organization: Apple Computer Inc, Cupertino, CA
Lines: 28

In article <8809291720.aa01487@SMOKE.BRL.MIL> LWELCH@COLGATEU.BITNET writes:
>Assuming I'm using GS/OS for everything, but I launch into ProDOS 8 applications
>as well as ProDOS 16 ones, which disks should I initialize as 4:1 and which as
>2:1?  How did the old ProDOS 16 initialize disks?
>I would guess that disks to be used by ProDOS 8 applications should be done
>as 4:1 and ProDOS 16 disks should be inited as 2:1 (with GS/OS)  Is this
>correct?
>

This is correct, but only if you are using the platinum Apple 3.5" drives. These
drives are able to take advantage of a special driver the GS/OS team created to
get the best performance out of a 3.5 drive. However, the older UniDisk 3.5
drives have their I/O routines in ROM in the drive itself, which aren't as
good or as fast as the one with GS/OS. Therefore, it can't read disks with
the 2:1 interleave very well.

By the way, the GS/OS team is very proud of the Apple 3.5" driver. After 
getting it to format a 3.5" disk in 34 seconds on the GS, they noticed that
it takes the Macintosh Finder on a Mac II *35* seconds. However, I haven't
tried this out to verify it; I'm afraid to...



Keith Rollin                                               amdahl\
Developer Technical Support                           pyramid!sun !apple!keith
Apple Computer                                             decwrl/
"You can do what you want to me, but leave my computer alone!"