Re: TI-H: Serial Link

To: ti-hardware@lists.ticalc.org
Subject: Re: TI-H: Serial Link
From: Greg Hill <gregh@xmission.com>
Date: Mon, 13 Apr 1998 11:16:19 -0700 (PDT)
Delivered-To: ti-hardware-outgoing@towerguard.unix.edu.sollentuna.se
In-Reply-To: <01bd6624$4d288980$02eaeacc@jrapp>
Reply-To: ti-hardware@lists.ticalc.org

On Sun, 12 Apr 1998, Jeff Rapp wrote:

> Ok, but this is what it does.  I plug it into the link port and the
> cursor blinks and the contrast drops like it's draining power out of the
> batteries.  Why? 

Ahh, back on topic. :)

When the serial link gets plugged into the calc and a serial port that
hasn't been initialized (by a linking program) the cursor freezes like
that. This is because when the link port is idle, both pins are floating
at about 5v. But when you plugged in the link cable, one or both of the
pins is near ground. So the calc pauses, expecting a link port
transmission (like a screen copy) and then just sits there because nothing
comes. This "feature" is actually helpful when you're finding which port
you are plugged in to. Start the link program and set it for COM1. If the
cursor doesn't start blinking after several seconds, try COM2. And so on
until the cursor blinks again.

You might also check your connections to the link port. If you're going by
the diagram with the link wire colors on it, don't. The TI link wire has
the red connected to one part of the connector, but many other link wires
have it on the other part of the connector. So just use a continuity meter
to find which color is connected to the tip of your link wire, and then
connect it to the rest of the circuit accordingly. The link won't work
when the two data lines are backwards.

-- 
Greg Hill
greg-hill@bigfoot.com
www.comports.com/link

References:

Re: TI-H: Serial Link

From: "Jeff Rapp" <jrapp@geocities.com>