RAM Expander

Subject: RAM Expander
From: A.K.A. TheWiz <dankna@BERGEN.ORG>
Date: Tue, 17 Sep 1996 13:08:46 -0400
In-Reply-To: <>
  I didn't get to list all my ideas before...


  For the computer-control, I'm thinking something like this:








                |                      |
                |  computer            |
                |                      |
                |                      |
                |                      |
                |     Serial Port      |
                 ----------------------
                      | $4 link | ($4 link because $5 is missing 2 pins)
                      | W  R  G |
                       ---------
                        |  |  |
                        |  |  |
----------              |  |  |
   TI     |             |  |  |
          |             |  | /|
  White---|--------TRANSISTOR--------
          |                | /
    Red---|--------TRANSISTOR------ (rest of the circuit)
          |
 Ground---|--------------------
          |
----------


  Where, IF THERE IS CURRENT coming from the PC ground, the lines are
routed to the PC rather than the calculator (we could also have a switch
to transform this into a standard TI-PC link).


  Second idea:
  This is a no-brainer:


  Put a 3.5 mm stereo connector in one side of the expander, with a
switch so the circuit just becomes a straign pipe through.  I said THREE.5 mm,
which is the size of a standard jack, and is MUCH easier to find than a
2.5mm one like the TI normally uses.  That way we don't have to keep
getting and cutting up more TI-TI links!


  These are just ideas; I really don't know that much about electronics
and I leave their development to whoever feels qualified.


  I've got a class now, but next time I'll talk about my proposed memory
data format for the RAM expander.


                     /***********************************
                     *           Daniel Knapp           *
                     *       FeatherWate Software       *
                     *     email: dankna@bergen.org     *
                     *                                  *
                     *      Whose account this is,      *
                     *         I think I know.          *
                     * The sysop is in Berkely, though. *
                     * She will not see me typing here, *
                     *        To watch this Mac         *
                     *          Refuse to go.           *
                     ***********************************/