Re: [stella] Paddle controller docs?

Subject: Re: [stella] Paddle controller docs?
From: Kirk Israel <kirkjerk@xxxxxxxxx>
Date: Tue, 17 May 2005 15:38:25 -0400
On 5/17/05, Thomas Jentzsch <tjentzsch@xxxxxx> wrote:
> C. Bond wrote:
> > 2) What is the approximate minimum and maximum delay times
> > from the start of charge to the activation of INPT0? (or
> > INPT1, INPT2, etc.)
> I don't know about the minimum, but the maximum is more than one
> frame.

Heh, this woulda been good for me to get to 2600 Cookbook.

One thing that might not be obvious: although the maximum is more than
one frame, many action games will only use a small fraction of the
paddle's total turning capacity, because human wrists just don't bend
that much.  So I think you can choose a range of the paddle that
should definately trigger within a frame.

> > 3) What is the best way to interrogate the paddles?
> Search the archives. We had some discussion about this.

I think the Best Practice is thought to be reading paddles inside the
display kernal, since that has to synch up with the  WSYNCs anyway, so
you can poll at regular intervals.

Obviously the kernal is already cramped since you have to display
everything. I wonder if you could get satisfactory results by
triggering the paddles right before or during the screen draw, then
reading in the overscan?

THe other option of course is to try to poll during your VBLANK code,
but that might be a world of hurt since you'll have to predict how
long all your code is taken under all conditions.

Like Thomas said, the stella archives might be your best bet.
Though if you end up whipping together some sample code to see when
you can get away with paddle reads, feel free to write up your
findings and the example for the Cookbook!

Heh...reminds me of my pipedream of getting some new 4 player games
out there...the trouble is 4 players who can move anywhere on screen
really tax the display capabilities of the 2600 and/or require flicker
and/or large amounts of cleverness.
Archives (includes files) at
Unsub & more at

Current Thread