Path: utzoo!attcan!uunet!super!udel!rochester!cornell!mailrus!ames!amdahl!oliveb!amiga!kodiak
From: kodiak@amiga.UUCP (Robert R. Burns)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Do all 3.5 inch drives use the same encoding
Summary: bits: yes, sectors: no
Keywords: MFM GCR
Message-ID: <3110@amiga.UUCP>
Date: 15 Nov 88 20:56:50 GMT
References: <8811101847.AA22940@godzilla.eecg.toronto.edu> <160@dms3b1.UUCP>
Reply-To: kodiak@tooter.UUCP (Robert Burns)
Distribution: na
Organization: Commodore-Amiga Inc, Los Gatos CA
Lines: 17

In article <160@dms3b1.UUCP> dave@dms3b1.UUCP (Dave Hanna) writes:
)...  The controller in the Amiga has the ability to use
)that [MFM] format, but the standard Amiga format uses GCR
)(Group Coded Recording), which is also what the Apple II used...

That's backwards.  The Amiga was originally spec'd to read/write Apple II
5 1/4" disks (for BASIC program portability), then Paula was revised to 
read/write IBM PC (MFM) 5 1/4" disks, then we went with 3 1/2" MFM disks
and the proprietary sector layout that allows the blitter to be used to
advantage to read sectors.

- Kodiak
-- 
| / _  _|' _ |/    Bob Burns               .  .    . . .---.  .
|/ (_)(_)|(_\|\    Ursa Major             / \ |\  /| | | __  / \
|\   Kodiak    \                  _______/ A \| \/ |_|_|___|/ A \
| \ Software                    "Dedicated to the Science of Fun"\_________