VECTORLIST - The Mailing List For The Technical Discussion of Vector-Based Arcade Games

July_1997
Re: Paul was right


From: Clay Cowgill ( )
Date: Fri Jul 25 1997 - 12:15:02 CDT


>Actually I was thinking the same thing!
>
>Read inputs
> Output G-80 spinner...
> Output Midway spinner...
> Output Dir & Clock...
> etc.
> loop

Right... The 2051 has about as many outputs as a 16C54 PIC around 13 or 14
I think. Those get eaten up fairly quick with 8-bit databus type outputs,
but since you don't need all the parallel functions (Midway, G-80, etc) at
the same time you can just do one, or trigger some external latches if you
want to...

>Even if you can't treat the flash as data, there is an instruction which
>allows you to do a lookup in code space, your tables will work just fine.

Oh, that's cool. I always used DPTR to index into data memory so I never
had to look for the alternative. ;-)

>The 17Cxx series of PIC processors also have an instruction for accessing
>code space as a table, too bad they're expensive and don't come in any "one
>chip does all" flavors. (Well at least they didn't four years ago...)

Still kinda spendy. I bet a 16C54 would do the job just fine. I just
don't like those funky PIC lookup/jump tables.

-Clay

Clayton N. Cowgill Engineering Manager
_______________________________________________________________________
/\ Diamond Multimedia Systems, Inc.
\/ Communications Division http://www.supra.com/


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