> My first reaction would be to include the intensity feature in the form of
> a DAC0800 (or 1408, or DAC08, or whatever you want to call it). Use a mux
> to switch between either the top 6 most significant bits for intensity
> based games, or the top lines tied together for "mono-intensity" games.
Solar Quest is the only multi-intensity game, and in my conversation with
Scott Boden (The games author) he said it was going to be a Color game
but they changed it last minute. For all we know it's still set up for
color! The interface to the multi-intensity and color interface boards
are the same which supports the idea of color SQ. My first reaction then
is to skip multi-intensity and go for color :-) There are no "mono-
intensity" games, all the others use 1 bit for intensity, but I agree
with the idea of using a mux to select what goes into the D/A. The
question remains if the 6-bit color is treated a 3 2-bit values or something
like Atari did with 3-bit color and 3-bit intensity. We need to look
into that.
> I'm thinking of the MAX503 (I think that's the one) for the D/A. 12 bit,
> parallel load, +-10V output, +5 supply, and two free samples from Maxim
> free for the asking... ;-)
Neat, how do they get that range from a +5V supply?
Ray and I have been talking about the differences between Cinematronics
and Atari WRT the D/A. Atari feeds a pair of integraters with the output
of the D/A while Cine uses it as a target position which they feed into
a pair of RC circuits (to do a rapid move, R is switched out of the
circuit). At that point, both systems have signals that are functionally
the same: voltage corresponds to position. Atari then uses 4 multipliers
to compensate for the non-linearity of the monitor, while Cinematronics
uses some strange diode thing :-) The Boxing Bugs color interface also
uses the multiplier chips common on Atari games.
Short term I'd like to replicate the Cinematronics D/A circuit and
feed the position signals into my Space Duel board before the multiply
chips. Long term we should probably replicate the Color interface but
with support for mono-games.
Just my thoughts, I'd be happy with ANYTHING that gets Cinegames running
in my house (other than the emulator).
-- ___ __ _ _ _ | \ / \ | | | || | Engineer/Programmer | _/| || || |_| || |__ " What makes someone care so much? |_| |_||_| \___/ |____) for things another man can just ignore. " -S.H.
