Re: [stella] Y Adapter

Subject: Re: [stella] Y Adapter
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Wed, 13 Feb 2002 22:24:00 +0100
> The way SWCHA maps to the controller ports:
> [L]   [R]  <-PORT
> 7654 3210  <-DATA BITS
> 4321 4321  <-PORT PIN NUMBERS
> 11XX 11XX  <-X = driving controller grey code

Actually the last line is supposed to be:
XX11 XX11  <-X = driving controller grey code

And for reading the the Booster Grip: Yes, you must ground the
capacitors each frame through bit 7 of VBLANK. Otherwise they
won't return to '1' when the button is released. Also, if you
want to allow the Colecovision joystick (or a modified Proline
controller) as an alternative, you should make sure that you
read the normal joystick button while the capacitors are not
grounded. The CV stick connects the button line with one of the
paddle lines. If you read the normal button while the capacitors
are grounded, you would get false triggers, when the second button
is pressed. (Sorry Thomas, I think I got that the wrong way round
the the e-mail I sent you).

Ciao, Eckhard Stolberg

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