Path: utzoo!attcan!uunet!lll-winken!csd4.milw.wisc.edu!leah!rpi!batcomputer!cornell!rochester!pt.cs.cmu.edu!ius3.ius.cs.cmu.edu!ralphw
From: ralphw@ius3.ius.cs.cmu.edu (Ralph Hyre)
Newsgroups: comp.sys.apple
Subject: Re: UniDisk or SmartPort on a card?
Message-ID: <4661@pt.cs.cmu.edu>
Date: 5 Apr 89 22:57:36 GMT
References: <1190@microsoft.UUCP> <28208@apple.Apple.COM>
Organization: Carnegie-Mellon University, CS/RI
Lines: 41

In article <28208@apple.Apple.COM> mattd@Apple.COM (Matt Deatherage) writes:
>In article <1190@microsoft.UUCP> brianw@microsoft.UUCP (Brian Willoughby) writes:
>The reason the UniDisk doesn't work on IIe and II+ computers is really simple:
>There's no interface card for it (from Apple).  The ...
>... card simply doesn't have the firmware (and maybe not the hardware)
>to run the Apple 3.5 Drive, mainly since the card was released two years before
>the drive was.
400 and 800K Mac Drives were around before this, of course, but Apple 
apparently hadn't fully committed to the maximal peripheral sharing strategy 
yet.

I think that a software solution exists, though.

The Uni 3.5 must have all of the hardware to talk to 'bare' 3.5 drives 
(it has an IWM and even a 6502 inside!)

Has anyone out there actually used the code downloading facilities
to shove code into the UniDisk itself that could talk to daisy-chained
Apple 3.5s?  (there is 32K of RAM in there to play with.)  I suppose the
first program I write for the UniDisk will be something that sends a
listing of the ROM contents back down the smartport, so I can better
understand what's going on:-)

If I can program the controller sufficiently, I could throw away my Disk
][ controller cards and hang everything of of my UniDisk 3.5.

Then I could use interrupts and multitask and do everything else that
these zlottin' 5.25 drives hamper.  (MIDI data collection is one item.)
I assume that the Smartport firmware is interruptable, reentrant, and all 
that.
I can depend on the co-processor in the Uni 3.5 to shuffle the nibbles around 
and communicate with the Apple ][.

One more thing for my ever-expanding TODO list.

BTW, How can I get the UniDisk 3.5 Tech Notes?
-- 
					- Ralph W. Hyre, Jr.
Internet: ralphw@{ius{3,2,1}.,}cs.cmu.edu    Phone:(412) CMU-BUGS
Amateur Packet Radio: N3FGW@W2XO, or c/o W3VC, CMU Radio Club, Pittsburgh, PA
"You can do what you want with my computer, but leave me alone!8-)"
--