From cisin@xenosoft.com Thu Jan 18 14:05:52 2001
From: cisin@xenosoft.com
To: test-drb@ccmp.vtda.org
Subject: Questions about TRS-80 Expansion Interface
Date: Thu, 18 Jan 2001 14:05:52 +0000
Message-ID: <Pine.GSO.4.21.0101181156540.1596-100000@lanshark.lanminds.com>
In-Reply-To: <Pine.LNX.4.10.10101181020250.2755-100000@siconic.com>
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On Thu, 18 Jan 2001, Vintage Computer Festival wrote:
> I need to know where the serial port connector is on a TRS-80 Expansion
> Interface.  I have two of them.  One has its ports labeled, and one of the
> ports is labeled "MODEM" but it is simply an edge connector.  Is this the
> serial port?  If so, what's the pinout?
> Any help would be greatly appreciated.  Thanks!

The connector is, indeed, simply an edge connector.  Sorry, I don't have
the pinout handy; check with Eric.

The serial port was an add-on board for the expansion interface.  It
resides in a compartment in the top of the E.I.

There were chronic problems with poor contacts connecting the serial port
board to the E.I.  Some folks soldered it, some wedged chunks of foam
rubber or other alien materials into the compartment, some fashioned
elegant spring steel brackets in an attempt to improve the connections.


For use with serial printers, there were also parallel to serial
converters, and TRS2332 and GPA which connected to cassette port and
expansion bus, respectively.  (There are some GPA's in the junk that you
got from me.)

--
Grumpy Ol' Fred        cisin(a)xenosoft.com
<A HREF= "http://www.xenosoft.com/dogears" >DogEars</A>

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