Re: [stella] Driving controller multitap

Subject: Re: [stella] Driving controller multitap
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Fri, 27 Feb 2004 00:14:06 +0100
> > But you can also use it for four-player joystick
> > or driving controller games, which might help getting more
> > programmers to support it.
> I thought of a solution where the the input signals would flicker. So you
> could utilize "4 kind of any controler" at once. On frame you'd read one
> controler, next frame the second. And this for both ports.

I was just giving examples. Of course you could design the multitap
in such a way that it would multiplex all the lines on the VCS
controller port. By switching between the multitap ports you could
read as many controllers in a single frame as your code can handle.
Since you have four bits to select the ports, you could even build
a multitap with 16 input ports, if you can think of a VCS game design
with that many players. ;-) Or you could use the unused joystick
button input on the right port to support two button joysticks or

I didn't use paddles as an example, because it takes a full frame
to read them and you only can access two paddles at a time with
the multitap, so it would take four frames to read them all on a
four port setup.

Your idea would work better for paddles. But as you say, synchronisation
would be a problem, since there are no other easily readable outputs
from the VCS other than the controller ports. And these are already
used for reading the controllers.

Ciao, Eckhard Stolberg

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