Date   : Tue, 06 May 1986 15:02:14 GMT
From   : Steve Corbin <corbin%encore.uucp@BRL.ARPA>
Subject: Commodore 128 Mouse Interface

I have just purchased a Commodore 128 mouse with the hopes of connecting
it to my Z80/CPM machine.  The only documentation supplied in the package
is the connector pinout.  Does anyone know where I can get the full
technical details for this device?  Items of interest would be schematics,
electrical and timing characteristics, suggested hardware interfaces, and
software drivers.


The connector is laid out as follows:

       PIN     SIGNAL
        1      UP
        2      DOWN
        3      LEFT
        4      RIGHT
        5      nc
        6      BUTTON 1 (left)
        7      VCC (+5v)
        8      GND
        9      BUTTON 2 (right)


The little I could tell about these signals is:

BUTTON #1, BUTTON #2

These lines are connected to one contact of the pushbuttons with the other
contacts to GND.  No pull-up or debounce circuitry.

UP, DOWN, LEFT, RIGHT

Active low signals indicating direction(s) of movement.  UP/LEFT, UP/RIGHT,
DOWN/LEFT and DOWN/RIGHT may be simultaneous and asynchronous with respect
to each other.  Questions are:

       1.  Are these lines pulsed for each 'step' of movement?

       2.  What is the resolution of movement? (i.e. steps/inch)

       3.  What is the minimum/maximum pulse width?

       4.  What is the minimum/maximum high time between pulses?

       5.  What is the output voltage levels?


Thanks in advance,
Steve Corbin

Usenet: corbin@encore
        {ihnp4, allegra, linus}!encore!corbin