Re: z80 card dip switches

[mjmahon@aol.com (Michael J. Mahon)]

In article <a2c2f792.0303090854.570f3c16@posting.google.com>, jon@i-manila.com
(Jon Co) writes:

>I have 2 z80 cards.  They are both unbranded.  About the size of a
>language card.  There's an LED in the top middle part of the card and
>4 dip switches under it.  One of the cards dont work as I tried to run
>it with all 16 possible combinations.  Since the chips are socketed I
>will be checking this card out later on part by part.  The other card
>worked on my //e.  What's the function of the dip switches?  The LED
>blinks when cp/m is in use and while programs are running.  Does cp/m
>make use of the //e's auxillary RAM? or does it run like it did on the
>II+?

Most CP/M cards, and the ones you describe, are clones of the
original Microsoft SoftCard.  The DIP switches must generally all be
set to the "off" position in normal use.  (There was a recent posting
here detailing the switches' functions.)

SoftCard clones do not usually use Auxiliary memory, since all the
software for them was written prior to the existence of the //e.
A later version of the SoftCard, designed for the //e, not only uses
auxiliary RAM, but is on the same card with it, and plugs into the
AUXRAM slot.

>Also, I did some experimenting and plugged the working card into my
>IIGS, and of course it didn't work.  either screen full of garbage or
>"cannot detect z80 softcard"

You need to have the IIgs running at 1MHz (slow) speed.  Some
older Z-80 cards may still not work because of slightly different
slot signal timings (ditto for //e).

>What software, besides cp/m required this z80 card?

That's it.

-michael

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