Path: utzoo!utgpu!watserv1!watmath!att!occrsh!uokmax!apple!julius.cs.uiuc.edu!psuvax1!psuvm!psuecl!d6b
From: d6b@psuecl.bitnet
Newsgroups: comp.sys.amiga
Subject: Re: AE HD Floppy
Message-ID: <20595.26ece153@psuecl.bitnet>
Date: 11 Sep 90 17:06:24 GMT
References: <3027@mindlink.UUCP> <2915@corpane.UUCP> <14336@cbmvax.commodore.com>
Organization: Engineering Computer Lab, Pennsylvania State University
Lines: 31

In article <14336@cbmvax.commodore.com>, daveh@cbmvax.commodore.com (Dave Haynie) writes:
>
>>How does the AE drives work anyway? I remember people asking Dave Haynie if
>>the new version (then called 1.4) of AmigaDOS would support 1.44 meg floppies
>>and the answer was no, because the chip that handles floppy access could not
>>support any larger drives. It was a hardware limitation. So, how is AE getting
>>amigaDOS to support high density drives?

I assume they're doing GCR at 2us/bit (it's possible...I've done it).
(With 2meg drives, of course; it doesn't work at all on 1meg drives).
You should be able to use their software with any 2meg drive. (Although
they could be using those strange sony drives that Apple uses to store
slightly more than you would normally get with 2us GCR).

[lots of good stuff by Dave deleted]

You left out an option - improve Paula. As explained in an earlier posting,
if you incorporated MFM encode/decode onto Paula, the memory bandwidth
requirements for 1us/bit MFM would be exactly the same. I don't
think the clock would be a problem...so it's a drop-in upgrade.
Why not do it???

-- Dan Babcock

P.S. This system (a VAX!) crashes every time I do a followup (register
dump, etc.). An email note saying "Yep, it went out" would be appreciated...
thanks.

> Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
>    {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
>       Get that coffee outta my face, put a Margarita in its place!