Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!gatech!hao!ames!ucbcad!ucbvax!hoptoad!farren
From: farren@hoptoad.uucp (Mike Farren)
Newsgroups: comp.sys.amiga
Subject: Re: Reading MacDisks on Amiga
Message-ID: <2112@hoptoad.uucp>
Date: Sun, 10-May-87 18:26:13 EDT
Article-I.D.: hoptoad.2112
Posted: Sun May 10 18:26:13 1987
Date-Received: Mon, 11-May-87 03:17:32 EDT
References: <8705080543.AA18112@cory.Berkeley.EDU> <112@l5comp.UUCP>
Reply-To: farren@hoptoad.UUCP (Mike Farren)
Organization: Nebula Consultants in San Francisco
Lines: 27

In article <112@l5comp.UUCP> scotty@l5comp.UUCP (Scott Turner) writes:
>
>First lets correct that statement about selecting speed, the Amiga DOES have
>such a register! Go read yer hardware manual again Matt.
>
News to me - could you please specify what you're talking about?  I
just put down the Hardware Ref. Manual and couldn't find such a beast.
There IS a bit for selecting 2 or 4 microseconds/bit cell, but that
isn't going to buy you a lot of flexibility.

>So [Apple] kept the variable speed part and switched to "stock"
>drives and media.  As a result Mac disks vary their speed from 400 to
>600 rpm.  Alot of people have stated that the Mac system is "brain
>damaged" because of it's use of variable speed and software decoded
>GCR.  Well that extra rpm cancels out quite a bit.

No, it just makes it more brain damaged.  If the extra speed thing is
true, then they should have been able to get a LOT more data onto the
disk than the 400/800K that they did.  Twice the rotation speed ==
twice the data rate, after all.  (Is this how IBM is getting 1.4M
3-1/2" drives, by the way?)

-- 
----------------
                 "... if the church put in half the time on covetousness
Mike Farren      that it does on lust, this would be a better world ..."
hoptoad!farren       Garrison Keillor, "Lake Wobegon Days"