[atari7800] Re: Paddles and trackballs

From: "Eckhard Stolberg"
> Which Trakball does your program read, the CX-22 or the CX-80?
> And how often do you sample new data? In my experiments with the
> Trakball on the 2600 I found that you'd need at least 20 values
> per frame for a smoothly moving cursor.

> The driving controller works the same way as the CX-80 Trakball
> (wich is the same as the ST mouse, BTW). But it only has one axis
> and a much lower resolution. So, if your demo is programmed for
> the CX-80, it should work with the driving controller too.

The zones are 8 lines high, so the DLI gets called 31 times per NTSC frame
(37 times PAL).  I think it's the CX-22 (don't have one myself) which has
one direction signal per axis (increment or decrement) and one movement
signal (change 0<->1).  Hmm, if the CX-80 woks like the driving controller
(grey code), then I'll just make my driving controller code read all 4 axes.

I do have a driving controller, so that I can test.  Unfortunately, I don't
have a light gun; and that would be much harder to develop without testing.

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