RE: [stella] RESPx and player positions

Subject: RE: [stella] RESPx and player positions
From: "John Saeger" <john@xxxxxxxxxxx>
Date: Thu, 23 Apr 1998 09:23:50 -0700
> >Hum.... I thought HBLANK lasted 68 color clocks?  So wouldn't 22 * 3 = 66
> >still be during HBLANK or am I counting something wrong?
> When I wrote trick.a65, I didn't do much cycle counting. I positioned
> the STA RESP0 at the earliest cycle possible by trial and error. I
> only noticed that it was cycle 22, when you brought it up.
> It might be possible, that the TIA finishes it's setup routine already
> at cycle 22, since cycle 23 ends one pixel in the display.
> This would explain the stange gun position in Atlantis. The
> RESPx might end at cycle 22, which would be 2 pixels before
> display time. If we add the strange 5 pixel offset, the gun
> would be at pixel 3. The HMOVE of 3 pixels to the left, that
> you mentioned, would put the gun right at pixel 1.

Interesting. This might also explain odd behavior of MS PACMAN (in emulators
anyway).  Forgive me, but where do I find a copy of TRICK.A65?



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