Re: Multigame update!

>> 1) When P1 start and P2 start are pressed simultaneously and held in for
>>1sec
>> NMI is asserted which calls the menu program. (neat, huh? :-)
>
>Holding P1 start and P2 start are commonly used to skip quickly through the
>games test mode, so I don't think this is a good idea (coming from a guy whose
>had to go through test mode +1000 times and couldn't live without this
>feature...). I vote for reset (or can't this be done?)

Ahhh, hmmmm. I don't really care *what* switches they are, just as long as
all the games had them and it was unlikely that the combination would occur
during game play (that was the idea behind the "press and hold for more
than a second" thing. I can do P1 start plus "fire" just as easily. That
shouldn't clobber anything...

Using reset instead... I'll have to think about that one. The handy thing
about the NMI was that it's a nice little hook already built in for me.
All I do is replace the vector for NMI in each game to point to the menu
code. The menu code is mapped in at locations 0xF000-0xF7FF which are
normally unused. The menu system sets a bank select/parameter register
pair that switches the low ROM area (0x0000-0xBFFF) to the appropriate
game, tells the Controller Controller what's going on, tells the screen
rotate logic whether or not to kick in, and then just jumps to 0000 to
restart.

>> 3) Remaps Impulse/Fire on StarTrek to match thrust/fire on the rest (yeah,
>> it's nit-picky but would bug me to no end if I didn't do it. ;-)
>
>Totally agree; it's a pain to switch these wires when I play Star Trek on my
>enhanced Tac/Scan control panel.

Good. It wasn't just for me then. ;-)

>> 4) Provides quadrature outputs from SF/Elim rotate buttons. (So the rotate
>> buttons on Space Fury and Eliminator can be used instead of the spinner
>> knob.)
>
>Optional right? (So you can use an encoder wheel if you have one)

Right. This was for Space Fury/Eliminator people that want to try
Zektor/ST/TS but don't want to switch control panels and/or don't have a
spinner knob around.

-Clay

Clayton N. Cowgill Engineering Manager
_______________________________________________________________________
/\ Diamond Multimedia Systems, Inc. clay@supra.com
\/ Communications Division http://www.supra.com/
Received on Mon Jun 2 13:50:22 1997