RE: Board tester board...

G'day folks,

One thing caught my eye about Clay's latest project. It looks like a
part that I might find useful for "conversions". With A-B-C-D boxes for
DB-25 readily available, I've always dreamed of making a JAMMA cabinet
to handle 16 different JAMMA games with five A-B-C-D boxes wired in a
two tier heirarchy where on box feeds the rest.

Power and audio probably shouldn't be routed through these switches with
the other signals, so Clay's design fits very nicely this approach.
Maybe I'd need a second set of switches (or relays run off of the DB-25
connector's selection) to switch power and audio (and RGB also, I
guess).

One comment...many modern JAMMA games use an additional connector (for
the extra buttons). Not sure how you'd handle that in Clay's project?

Is this feature creep? 8^) 8^) 8^)

               Steven S Ozdemir
               sso@plpt.com (my company renamed itself in Feb)
               sso@dsc.com (good for a few more months)
               ozdemir@xenon.stanford.edu (permanent...weekly)

>----------
>From: Clay Cowgill[SMTP:ClayC@diamondmm.com]
>Sent: Thursday, February 26, 1998 3:21 PM
>To: 'vectorlist@spies.com'
>Cc: Clay Cowgill
>Subject: Board tester board...
>
>So a while back I brought up the idea to make a "universal" test board
>for working on game PCB's.
>
>The idea was to make something that would plug into a game board
>directly (56 pin, 44 pin, or 36 pin) and provide a simple connection to
>a PC power supply; provide lots of test points for jumpering; have a
>small onboard audio amp; provide "standard" connectors for
>control/video/audio connections; lots of taps for +5, +-12, etc.
>
>We kicked around other ideas like adding color inversion for
>Nintendo-type audio outputs, sync combination (select
>positive/negative/composite), and stuff like level convertors for
>different types of vector games.
>
> AAAAAAAAAAAAAAAA
> +------------------+
> | | <-- card edge adapter
> ------------------
> | |
> | |
> | | <-- test connector board
> | |
> | PWR RGB CONT AUD |
> +------------------+
>
>A = 56, 44, or 36 pin .156" connector
>PWR = .156" power connector post to match PC-AT power supply
>RGB = DB-9 pin connector
>CONT = DB-25 pin connector (two joysticks, six buttons, p1/p2 start,
>coins, etc)
>AUD = onboard speaker and amp, headphone jack output for amplified
> "computer" type speakers.
>
>So you just plug it into the cardedge of a board and use little
>alligator-clip jumpers to connect your voltages, controls, and signals
>where needed. It's not exactly an "innovation" or anything, I just
>think it'd be a much nicer (for me anyway) way of testing "unknown"
>boards.
>
>The thing I can't decide is how to do the test points. I want to have
>at least 3 or 4 points on each trace coming off the connector so that
>you have plenty of posts to connect aligator clips to when testing. Do
>you think that standard .1" header posts are good enough? Maybe on .2"
>spacing? (So I'm thinking of getting 8 pin DIP headers, removing every
>other pin to make room for clips, and putting one of those on each trace
> from the edge connector.) Heavier "posts" (like Atari's test points)
>are comparitively spendy and take up a lot of PCB space.
>
>If anyone of you have input I'd like to hear it...
>
>-Clay
>
Received on Thu Feb 26 15:53:02 1998