Subject: Re: Game port
From: Rubywand <rubywand@swbell.net>
Date: Thu, Dec 24, 1998 152
Message-id: <368200B6.DC8E7976@swbell.net>



David Wilson writes ...
> 
> Rubywand <rubywand@swbell.net> writes:
> >     Okay. Thanks for correction. How about this ...
> 
> Getting closer.
>

     So far, so good!

 
> > DB-9 Female Socket on Computer      DB-9 Male Plug on Mouse
> 
> Those should read DE-9. DB-9 does not exist :-)

     Good to know. This led to a check through eem99 plus a couple
catalogs. Actually, it looks like nobody uses "DB" or "DE" anymore.
7-pin, 9-pin, 25-pin, ..., they are all called "D Sub" connectors now.

> 
> Looking at the //c technical reference I found that pin 4 of the DE-9 (XDIR)
> can be read as a digital signal at $C066 in place of the non-existant PDL2.
> Pin 8 (PDL1/YDIR) can be read digitally at $C067 in place of PDL3. These are
> standard TTL inputs (to a 74HCT251) so may not have the same limitations that
> the other digital inputs have.
 ....

     The new info is added-in below ...



 Dsub-9 Female Socket on Computer    Dsub-9 Male Plug on Mouse
     ,---------------------.          ,---------------------.
     \  5   4   3   2   1  /          \  1   2   3   4   5  /
      \   9   8   7   6   /            \   6   7   8   9   /
       `-----------------'              `-----------------'

   Mouse         Usual //c, IIc+ Game Port Function

1  MOUSE ID      Pushbutton 1
2  +5V           +5V
3  GND           GND
4  XDIR          no Game Port function on //c, IIc+;
                 this TTL-compatible input can be read at $C066
5  XMOVE         Game Control 0 or PDL0 (Joystick X-axis)
6  n.c.          (no Game Port function on //c, IIc+)
7  MOUSE BUTTON  Pushbutton 0
8  YDIR          Game Control 1 or PDL1 (Joystick Y-axis)
9  YMOVE         no Game Port function on //c, IIc+;
                 this TTL-compatible input can be read at $C067


     One thing, are YDIR and YMOVE correct? XDIR goes to a TTL input.
Should pin 9 be YDIR and pin 8 be YMOVE?



Rubywand