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From: brianw@microsoft.UUCP (Brian Willoughby)
Newsgroups: comp.sys.apple,misc.forsale
Subject: Re: WANTED - AppleCat II & Disk II Card
Summary: UDC works great with Apple 3.5 Drive and 65C02
Message-ID: <7647@microsoft.UUCP>
Date: 7 Sep 89 22:50:12 GMT
References: <3832@ncsuvx.ncsu.edu> <3829@wpi.wpi.edu>
Reply-To: brianw@microsoft.UUCP (Brian Willoughby)
Organization: Microsoft Corp., Redmond WA
Lines: 29

In article <3829@wpi.wpi.edu> greyelf@wpi.wpi.edu (Michael J Pender) writes:
>Well its not exactly a disk II card, but I have a Central Point UDC card
>I'd let go for $50.  
>
>A question for II+ owners, can a UDC be used on a II+?

ONLY if the II+ has a 65C02 installed, not a W65C802 or the original
6502.  This statement is based on the 6502 specification, the use of the
RDY signal by the UDC, the Laser representative I talked to, and my own
observations.  Actually, Laser does not support the Plus with their UDC,
but it will work with a 65C02 (around $8.00 from JameCo) installed - at
least it does on mine.

Some of the regular readers of comp.sys.apple may remember my complaints
about the UDC in combination with the TransWarp and/or C802, BUT I have
no disk errors at all with the 65C02 at normal speed.  If you don't have
a TransWarp, or the desire to use the W65C802 (around $17.50 from WDC),
then I highly recommend the UDC in combination with the Apple 3.5 Drive,
which is 6.4 times faster than an External Mac 800K drive or the various
Laser 800K drives (which are basically clones of the older Ext Mac 800K)
when they are hooked up to the UDC.  The 6.4 times speed factor was
measured by timing a Copy II Plus disk verify of all 1600 blocks on both
Apple 3.5 disk drive models.

Brian Willoughby
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