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Date: 30 March 1982 15:36-EST
From: Glenn A. Iba <GAI at MIT-AI>
Subject: Apple CPM / Softcard intermittancy and patch
To: Boebert.SCOMP at MIT-MULTICS
cc: GAI at MIT-AI, INFO-APPLE at MIT-AI
Via:  Mit-Ai; 30 Mar 82 15:46-EDT

   After trying out my softcard (in slot 4) with a videx videoterm
in slot 3, I too experienced severe problems with intermittancy,
in particular the cpm system would not even boot reliably.
I called Microsoft and discovered that this problem is common (they
extimate 20% but we got burned 2 out of 2 times) with Softcards
older than a few months. Apparently RF noise is the culprit and the
video boards create a lot more of it.
  FIX (fortunately there is a fairly simple fix):
What is needed is a 220 pF (50 VDC or greater) ceramic capacitor
(I got 2 for 30 cents at Radio Shack). This capacitor should be
installed between pins 10 and 11 of the chip at position U15 on
the Softcard board (this is at the extreme upper right of board,
and the pins are at the right hand end of chip). I did the modification
myself against the advice of Microsoft, who said they will pay any
dealer $7.50 to do the work (though this is a time-limited offer).
But for $.30 do you really trust a dealer with your $250 board??
  DO YOU NEED A FIX???
Your card already has the fix if there is a conspicuous insulated wire
on the backside of your Softcard (yes it runs to a 220 pF capacitor).
The newer Softcards have this installed.
  This patch immediately solved my intermittancy problems (I left the
Softcard in slot 4 right next to the videoterm).

Date: 30 March 1982 18:46-EST
From: Glenn A. Iba <GAI at MIT-AI>
Subject: Configuring Mince for Apple CPM with Videx Videoterm
To: AMETHYST-USERS at MIT-AI, INFO-APPLE at MIT-AI
cc: GAI at MIT-AI
Via:  Mit-Ai; 30 Mar 82 18:54-EDT

Now that I got my Softcard working properly I set out to configure
my MINCE system, but I had a real rough time trying to define
a new terminal type for the videx 80 column board. Then I decided
to try out each of the standard terminal types offered, and what do
you know, but 2 of them seemed to work perfectly!! The two were:
the SOROC IQ120 and the ADM31 (not the ADM3A). What I'm wondering
is:
   1. Are there any differences between these two (particularly
effeciency) that would recommend one over the other?
   2. Are there any hidden incompatibilities between either of these
terminal types and the videx videoterm?
   3. What was I doing wrong when I tried to specify new terminal
type (I copied the character sequences right out of the videx manual)??
Alternatively, what are the sequences used by Mince when either of 
those terminal types is selected?