Okay.  To apologise for the faux-pas that I made last week with the none-
working rotary controller for Tempest 2000 I've designed one that does work,
and I've tested it.  I made a mock-up with an old Atari mouse
because I couldn't find a cheap component that acts as a
optical shaft encoder except for the one in the mouse.  From this design
you can make a rotary device by cannibalising the mouse's X direction.

Because it seems so easy to make a mouse adaptor for the Jaguar I think
this will be my next stage.  Does anyone have any suggestions for which
joypad buttons are left and right on the mouse?  I guess you are all
wishing that Cannon Fodder had a mouse controller option now!

Here are my notes (longish):

---------------

        Do-It-Yourself Atari Jaguar Rotary Controller Pt. 2
        ---------------------------------------------------
                               by
                        Andrew Hague BSc.
                        -----------------

Here is an ASCII schematic circuit diagram for connecting up a mouse to act as
a optical shaft encoded rotary controller to the Jaguar (works with Tempest
2000 - I've tried this one!).  Basically you plug the mouse into the 9pin
plug, plug the 15pin plug into the Jaguar and set Tempest 2000 to use rotary
controllers.  Now left and right motion of the mouse will make left and right
motion on the Tempest play screen.

It doesn't discuss the construction but does give an idea of the components
you require and how they are connected.  You will need a basic knowledge of
electronics and soldering.

NOTE: This is for information only.  If you decide to build a mouse connector
using these notes then I cannot be held responsible if what you attach it to
blows up.  At this current time of writing this design has been tried out and
does work.  It only follows some backwards engineering of the joypad, hacking
with some code on an Atari Falcon and a few clues from knowledgable people.

-----------------------------------------------------------

You will require for the full implementation;

Basic (need for the guts of the device):
1 x 15 pin HD D-type plug and hood.
1 x 9 pin D-type plug and hood.
1 x 74LS32 (Quad 2-input OR gates).
1 x 0.1 microF capacitor.
1 x 1Kohm resistor.
some 8 core wire.
Lots x bits of wire.
Any old Atari Mouse.

-----------------------------------------------------------

Pins on Jaguar's HD15 connected to Mouse and IC.

             
        J4 ---------- I1
                |
                |
                |---- I4

        J7 -----+---- I14
                |
                |
                |---- M7
             
             
        J9 -----+---- I7
                |
                |
                |---- M8

        J11 --------- I3

        J12 --------- I6


Pins on mouse's D9 connected to IC

        M1 ---------- I2

        M2 ---------- I5
 

IC 74LS32, the writing the right way up!

(NOTE: connect the 0.1uF decoupling capacitor to pins I14 and I7 of the IC
close to the IC.  Also connect pin I14 to the 1K resistor and then connect
this resistor to pins I9, I10, I12 and I13 thus tying the unused inputs
high.)


  I14 I13 I12 I11 I10 I9   I8
___|___|___|___|___|___|___|__
|                            |
|       74LS32               |
|____________________________|
   |   |   |   |   |   |   |
  I1  I2  I3  I4  I5  I6  I7

Joypad pin numbering from the front of the jaguar, back of a HD15 D-type
plug.

     -------
J5  / ..... \ J1
J10 | ..... | J6
J15 \ ..... / J11
     -------

Mouse numbering from the front of the mouse, back of a 9pin D-type plug.
    -------
M5 / ..... \ M1
M9 \ ....  / M6
    -------


---------------------------------------------------------------

All contributions to the Hague fund, postcards and letters welcome.

Andrew Hague
188 Tang Hall Lane
YORK
YO1 3RL
ENGLAND
(andrew@minster.york.ac.uk)