Re: Apple UniDisk 3.5 vs. Apple 3.5

[spec@vax2.concordia.ca (Mitchell Spector)]

In article dempson@actrix.gen.nz (David Empson) writes...

>Mitchell Spector <spec@vax2.concordia.ca> wrote:
>
>>     If using a UniDisk 3.5 on an Apple IIgs, it should be connected 
>> directly to the Smartport in back. A UniDisk 3.5 connected to the 
>> SuperDrive card will not operate under GS/OS, and the same most likely
>> applies with the Liron card (I'm not certain whether the Liron will 
>> work in a IIgs at all, though I may very well be wrong).
> 
>What gave you the idea that a UniDisk 3.5 wouldn't work under GS/OS with
>a SuperDrive card?

    Apple's 'Apple II 3.5 Disk Controller Card Owner's Guide' booklet
that came included with my SuperDrive card. From Chapter 1, the bottom 
of page 2 (fourth paragraph) it reads:

"If you want to use UniDisk 3.5 drives with your computer, there are 
special configuration rules that you must follow. Specifically, this 
card doesn't support UniDisk 3.5 drives on an Apple IIgs running GS/OS, 
you must connect them to the built-in Smart Port on the computer's back 
panel."

>It is supposed to work fine, according to the documentation for the
>SuperDrive card, and the release notes for System 6.0.  It wouldn't work
>with earlier system software versions.  You MUST have the UniDisk3.5
>driver installed to use this drive under GS/OS (no matter where it is
>connected).

    The manual was printed when the lastest System Software release
was System 5.0.4, I guess that would explain it.

>I just plugged in a UniDisk 3.5 to my SuperDrive card (daisy chained
>after the SuperDrive), and it seems to work fine (System 6.0.1).
>
>The Liron card does not work in a IIgs (due to an issue with the bus
>interface - either an electrical or timing problem, but I don't recall
>the exact details).

    At least I was correct about that then. :) Still, in either of 
the two above cases, there is no point in connecting a UniDisk 3.5 
to an interface board when it works directly with the built-in 
Smartport (unless you have a faulty IWM or other logic). Not too
mention the fact that a UniDisk 3.5 is quite slow, an Apple 3.5
drive should be used on a IIgs whenever possible.

Mitchell Spector
spec@vax2.concordia.ca