Re: Cinematronics sound board behavior...

On Thu, 24 Jun 1999 13:38:15 -0700, you wrote:

>> The thing that concerns me though, is that you might need a differently
>> programmed 16V8 for each card. Many of the cards use a DATA/CLOCK shift
>> register to expand the 6 I/O lines to as many as they need. There is then
>> a
>> third LATCH line to latch in the shift register to the latch used to drive
>> the
>> sound circuits.
> [...]
>> Tailgunner used a totally different approach. A 3 to 8 mux. This would
>> also
>> need to be in the 16V8.
>>
>Well, I'm pretty sure I can handle all that in one of my big CPLD's I use on
>the multigame stuff. Would you happen to have a little interface
>description for each "type" of sound interface? (Just so I could come up
>with a basic macrocell count and whatnot.)

I'll send you what I got so far...

>> I don't think you'll need to generate 8 simultaneous channels. The Boxing
>> Bug
>> card contains more than 10 sounds (12? 13?). I'm sure they don't play all
>> at
>> once. Of course you will need some kind of logic to map the 12 channels
>> to the
>> 8 slots as their needed. This kind of coding can eat up cycles fast (as
>> lookup
>> tables are accesses, etc.)
>>
>I was originally thinking 4 voice, but thought that might not be enough so I
>just doubled it. All the more I was thinking for steering logic was just
>using a byte as flags-- test bits and when I find a zero, set it to one and
>use that channel for the next required sound. The sounds are just stored in
>absolute locations on the SmartMedia card with a little FAT for each game
>that's loaded into Scenix RAM (based on game select lines on the inputs)
>depending on what game is selected on a reset.

8 might do it. The worst case would be with a background motor
playing, while a player fires a shot, and an explosion is happening,
and a helicopter is flying onto the screen, at the same time a "free
time" bonus beeps, and the helicopter is firing at you.

And that's only 6 simultaneous sounds!

-Zonn
Received on Thu Jun 24 19:37:43 1999