Re: [stella] My demo...

Subject: Re: [stella] My demo...
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Mon, 28 May 2001 14:43:42 +0200
> > The missile works in z26 1.35, doesn't work in z26 1.45... I'm reading
> > fire button on INPT4, is this right? INPT5 is for joystick #2?
> INPT4 is correct, but you should check only for bit 7 (just change bne to
bmi). The other bits are used for something different (which i can't
rembember now), and are not always zero.

Actually these bits aren't used for anything. The programming manual lists
them as 'undefined'. I think on the 2600 they just keep the data that was
on the bus last. The Stella emulator always sets these bits to '1', PCAE
always sets them to '0', and z26 sets them to the lower bits of the address
of the register that currently gets accessed, as this most of the time
seems to be what was on the bus last. At least it fixed the problems in
Video Pinball, which seems to rely on a certain state of these bits.

As for the colours, the one you chose for the water is torquise, which
is somewhere in the middle between green and blue. Chosing the 'real'
colours for the emulator is quite difficult, since the colours can be
tuned in the VCS, on the TV, and on the PC monitor. So what you see
on your TV and on your monitor is pretty much different for everyone else.
I think Brad just chose the colours to be what they should be ideally
by the desription in the programmers manual. Both Johns seem to have
tried to match the colours on their TVs with the colours on their
monitors running their emulators. Which of the three emulators fits
the colours on your TV best is something that you have to find out
on your own.

Ciao, Eckhard Stolberg

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Current Thread
  • [stella] My demo...
    • Gonzalo - Sat, 26 May 2001 11:36:49 -0400 (EDT)
      • <Possible follow-ups>
      • Thomas Jentzsch - Mon, 28 May 2001 05:43:40 -0400 (EDT)
        • Eckhard Stolberg - Mon, 28 May 2001 09:15:24 -0400 (EDT) <=
        • Gonzalo - Mon, 28 May 2001 18:32:40 -0400 (EDT)
          • Joe Grand - Mon, 28 May 2001 22:51:32 -0400 (EDT)
          • Sark - Tue, 29 May 2001 07:54:10 -0400 (EDT)
          • Eckhard Stolberg - Tue, 29 May 2001 09:28:38 -0400 (EDT)