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Document Title: [WilliamHWfailures.html (html file)]

Typical Failures of Early Williams Games
From: woodcock@crchh75b.bnr.ca (Gregg Woodcock)
Newsgroups: rec.games.video.arcade.collecting
Subject: Re: Typical Failures of Early Williams Games
Date: 22 Feb 1994 23:29:15 GMT

richard.l.schieve (rls@cbnewsc.cb.att.com) wrote:
> Several people have asked me to repost some of my old articles.
> I suspect many have seen the following which was one of my first
> "Tech Tips" ;-)

Sorry to do this to you again, Rick, but I have added a BUNCH of stuff
to your file and would like to "share", too (I can never start these
files but *BOY* can I update them :).  Here is my revised text.

=========

Well, I've been collecting, fixing, and restoring mostly early 80s video
games for around 8 years now and have gotten pretty good at working on
them.  Some of these games have the same problems over and over and I
thought some of you might like to hear about some of these problems.
Much of this is information I've sent directly to people when they have
posted requests for help.  I'm not an electronics wizard or anything.
I've just spent enough time trying to fix games that I've learned some
typical failures.

Todays Tech Tip is on the early Williams games, Defender, Joust,
Robotron, Stargate, Sinistar, Bubbles, and I think Blaster but I've
never worked on one.  NOTE:  Defender comes in 2 flavors, the standard
Williams package (discussed herein) and a more compact 2 board version
done by Taito (not discussed).  Defender has several other important
differences, too (ROM boards are different).  Sinistar uses different
ROM and interface PCBs than the other games but the rest of the boards
are the same.  Some versions of Stargate contain a CPU board which will
only work in Stargate and none of the other games.

One quick errata before we begin in regards to the Williams manuals:
Some of them (Stargate and Joust for sure) drawings are incomplete.
Your interboard wiring drawing probably shows video coming out of a 7
pin connector (IJ3 "Monitor Control") as follows:

N/C    7
H Sync 6
V Sync 5
GND    4
Blue   3
Green  2
Red    1

If so, it's wrong.  Composite sync is available at the unused pin
(number 7 cabled "N/C").  It is indicated on the schematic pages but not
on the wiring harness diagram.  The problem with this sync is that it is
an active high composite sync so you have to run it through a TTL
inverter as MAMMA is looking for active low composite sync.

These games all share the same basic logic board arrangement as follows:

+-----------------+    +----------+          +----------+  +-----+
|                 |    |          |          |          |  | S A |
|                 |    |          |          |          |  | P U |
|                 |    | ROM/PIA  |          |  SOUND   |  | E X |
| CPU/VIDEO/RAM   |    |          |          |          |  | E S |
|                 |    |          |          |          |  | C N |
|                 |    |       *  |          |          |  | H D |
|                 |    +----------+          +----------+  +-----+
|                 |
|          X X X  |    +--------+
|          X R X  |    |INTER-  |
|          X A X  |    |   FACE | <--INPUT
|          X M X  |    +--------+
|          X X X  |
+-----------------+

Here is a blowup of the "X" area of the CPU/VIDEO/RAM board:

       BANK   BANK   BANK
        3      2      1
                          :
C 1    3K,31  2K,21  1K,11|
                          |
H 2    3L,32  2L,22  1L,12|
                          |
I 3    3M,33  2M,23  1M,13|
                          |
P 4    3N,34  2N,24  1N,14|
                          |
  5    3O,35  2O,25  1O,15|
                          |
N 6    3P,36  2P,26  1P,16|
                          |
U 7    3Q,37  2Q,27  1Q,17|
                          |
M 8    3R,38  2R,28  1R,18|
     ..-------------------+

If your game is not working, the first thing you should do is open up
the cabinet and locate the 7 segment (alpha-numeric) "digital" LED on
the ROM board (denoted by the "*").  Watch this when the game first
turns on.  Normally, it will show "0" and remain that way.  If there is
a detected failure, the display will repeatedly cycle 1 or 3 numbers.
The first number is the failure type; 2=ROM, 1=RAM, 3=CMOS RAM.  For ROM
errors, the last 2 digits are the ROM number (ROMs should have stickers
which are labeled to tell you which ones they are).  For RAM errors, the
last 2 digits are the Bank number and then the chip number (see previous
picture).  For CMOS RAM, there are no other digits.  SPECIAL NOTE:  Some
(all?)  Defender ROM boards do not have the digital LED but instead have
a row of 4 regular LEDs.  I do not have a Defender manual so I am not
sure about how to read these lights other than the fact that they only
indicate the bank numbers for RAM errors; there is no chip number
information.

If you have a ROM error, you can just burn a new ROM for it (try
reseating it first).  Most (if not all) Williams games use the same ROM
board with different ROM data for different games.  These ROM boards can
be configured for either 2532s or 2732s.  There are 2 pairs of jumper
locations which determine which type of ROMs go in the board; they are
W1/W2 and W3/W4.  These jumpers are just to the left of ROM 5 (W1 to the
far left, W2 to the right of W1) and to the left of ROM 6 (W3 to the far
left, W4 to the right of W3).  Jumpers W1 and W3 configure the board for
2532s while jumpers W2 and W4 configure the board for 2732s.  It goes
without saying that these are mutually exclusive pairings.  SPECIAL
NOTE:  Some (all?) Defender ROM boards differ slightly from the other
Williams games (they even have slightly different connectors) but since
I don't have one, I am not sure about jumpers, etc.

By far the most common failure of these machines is the DRAM (type 1
failure).  This usually will produce a very organized "rug pattern" on
the screen and the game will not "boot".  Sometimes you get really weird
video or else none at all.  The solution is simple, get new DRAMs!
These are type 4116 (450 ns access) 16K x 1 Dynamic RAMs and the
cheapest places I have found are B.G. Micro at 214.271.5546 for 40
cents each and Altex in San Antonio, TX at 800.531.5369 for $1 each.
This is an obsolete part so prices are bound to vary *wildly* due to
local supply/demand.  I am sure some of you can find them for pennies.
If you want to pay through the nose, you can buy NTE2117 parts ($15+
near me).

The three boards on the left are often mounted on a metal plate.  The
sound board is the same one used in pins and the AUX SND (speech) board
is only used in Sinistar (I'm not sure on Blaster).  The DIP switch at
DS1 is supposed to enable/disable any auxiliary boards (like the AUX
SND) and should not effect any game that does not have one.  Here are
some quick notes (from page 14 of the Sinistar Drawing Set 16-3004-103)
about the jumpers on the sound board and how they configure different
games:

JUMPERS USED     ROM TYPE    FORMAT    GAMES USED IN
W2,5,7,9,10,15    2K x 8     Sound &   Gorgar, Blackout Firepower, Black
                 2516/2716   Speech    Knight, Jungle Lord, Pharaoh
W1,2,5,7,9,10,15  2K x 8     Sound     Defender (video & pin), Solar Fire
                 2516/2716   only      Barracora, Hyperball, Stargate,
                                       Cosmic Gunfight, Varkon, Time
                                       Fantasy
W3,4,5,7,10,15    4K x 8     Sound &   Sinistar (upright & cockpit front)
                   2532      Speech
W1,3,4,5,7,10,15  4K x 8     Sound     Robotron, Joust (video & pin),
                   2532      only      Bubbles, Sinistar (cockpit rear),
W1,2,4,5,7,10,15  2K x 8     Sound     Warlock
                 2516/2716   only
W1,3,6,7,9,11,12  512 x 8    Sound     Big Strike
15                 7641      only

The next most common problem I've seen with these games are loose
connections that can become intermittent and sometimes overheat.  How
the loose connections affect on the game depends on where it is.  All
these boards including the power supply boards not shown are
interconnected with female Molex connectors mating to male pins that are
mounted perpendicularly to the boards.  These male pins are fairly heavy
gauge and are a bit hard to solder to.  The solder connection between
the board and pin often cracks when taking the connectors on and off.
Also, at the female end, the connection can overheat if things get a bit
corroded actually burning the connector shell and the female pin looses
it's spring tension.

People often complain of resets during game play.  There are some
software bugs (at least in Robotron) but more often than not the resets
are due to the +5 VDC supply dropping below what TTL devices can operate
with at the logic board itself.  The Molex connections to and from the
power supply board will often show signs of overheating.  Try measuring
the +5 at the power supply and again at the logic boards.  If there is
much of a difference and especially if the logic board is seeing less
than +4.7 or so you have problems.

If the female end has overheated considerably the female pin itself has
lost spring tension and should be replaced.  Often you can clean the
male pins and work the female off and on a few times to get by for a
while but chances are the female pin should be removed and replaced.
Many hack artist coin-op repair types will simply cut off the female
connector and solder wires right to the male pins.  You see the same
problems with Williams pinball games.  If the physical connections are
OK, try varying voltages from 4 up to 6 volts.  I have seen machines
that refused to work properly except in the range of 4.5-4.7 and others
in the range of 5.5-5.7 so you will just need to experiment to see what
voltage will keep your boards running without resetting.

BTW, the software Robotron bug is supposed to go away if you turn off
the "Fancy Attract Mode" which does away with the explosion when you zap
a bad robot (thanks George).

Loose connections at the logic boards seem more often to be cracked
solder joints where the pins go through the boards.  Any time unexpected
things start happening while playing, it is worth the time to pull the
board and check out the solder joints.  I checked out about 6 board sets
the other day and half didn't work but were fine after I resoldered the
pins to the boards.

Also, make sure to clean excess flux after resoldering the pins.  I've
seen too much left over flux scramble the inputs from the control panel.
To clean excess flux I use 1,1,1-Trichloroethane called Carbo-Chor at
Ace.  It's amazing stuff as as strongly as it smells and as well as it
works it does not burn so it relatively safe to use.  I use one of the
cheapie stiff bristled "glue" brushes and dip it in some trichlor and
scrub away.

One last thing, some versions of the CPU board which were only released
inside Stargate games are incompatible with other games.  If an unknown
CPU board won't work in your Williams game, try it in a Stargate to be
sure it is defective.  Does anybody know how to tell just by looking if
the board is of this type?  I have seen 5 different labels on these
boards; , Rev , Rev B, Rev C, and Rev D.  If it
works in Stargate, you can modify it to work in the other games.  Here
is a document from the October 1982 Star*Tech Journal that describes the
procedure:

====================================================================== 
=========

Williams "Stargate" and "Robotron" PCB compatibility

CPU/VIDEO BOARD
CPU/Video Boards from "Stargate" may be used in "Robotron" by making two
cuts and adding two jumpers.  Modified boards and "Robotron" CPU/Video
Boards may be used in "Stargate".  Use a 27 watt or smaller (preferably
grounded) soldering pencil and 60/40 solder for all soldering
operations.  Foils may be conveniently cut with a few strokes of a
pocket or exacto knife.  Use #22 or small gauge wire for the jumpers.
See illustrations below [illustrations omitted for obvious reasons; the
text steps are my descriptions of the pictures]:

   1.  On the chip at location 5A (under C63), cut the foil (trace) that
       connects pin 3 to ground.
   2.  On the chip at location 6F (under C75), cut the foil (trace) that
       connects pin 3 to ground.
   3.  Jumper the newly isolated pin 3 of both chips together.
   4.  Jumper pin 4 of the chip at location 5A to the feed thru hole
       (unused via) leading to pin 32 of connector IJ4 (above R26).

NEW POWER SUPPLY BOARD
Early "Stargate" games had a one piece D-8359 Power Supply Board
Assembly.  In "Robotron" and later "Stargate" games, this assembly has
been superseded by the new D-8474 Power Board and outboard heat sink
assembly C-8807.  The new board features crowbar overvoltage protection
on the +12vdc and +5vdc regulated outputs.

NEW TRANSFORMER
On upright and cabaret model games, a new power transformer with 8
primary and 12 secondary terminals (part no. 5610-09658) has also been
substituted for the old transformer with 8 primary and 9 secondary
terminals (part no. 5610-09353).  The new transformer includes a 12.6v
center-tapped secondary.  Secondary terminal 20 and center-tap terminal
19 provide 6.3vac general illumination power to pins 14 and 15 of plug
4P1.  Cocktail table model games continue to use a third power
transformer with 6 primary and 9 secondary terminals (part no.
5610-09629)

UPRIGHT GAMES
New Transformer - new Power Supply:  W1 in, W2 & W3 out.
Old Transformer - new Power Supply:  W2 & W3 in, W1 out and 2 ohm 5W
resistor added at R27.  Pins 13, 14, & 15 of 4J1 are left disconnected
when transformer secondary plug is connected.
New Transformer - old Power Supply:  Pins 13, 14, and 15 of 4P1
(transformer secondary connector) are unterminated at Power Supply 4J1
12-pin connector.

COMPACT (COCKTAIL) GAMES
New Transformer - new Power Supply:  W1 in, W2 & W3 out.
Old Transformer - new Power Supply:  W1, W2, & W3 in.  Pins 13, 14, & 15
of 4J1 are left disconnected when transformer secondary plug is
connected.
New Transformer - old Power Supply:  Pins 13, 14, and 15 of 4P1
(transformer secondary connector) are unterminated at Power Supply 4J1
12-pin connector.

====================================================================== 
=========

To people that have worked on these (and older Williams pinballs) this
is all old news.  I think that many that read this group have not had
their hands in a machine until they are forced to and often have
software backgrounds and are a bit afraid of the hardware.

				Rick Schieve
				rls@ihlpb.att.com

additions by    Gregg Woodcock
                woodcock@bnr.ca


From dholcomb@microsoft.com Tue Dec 13 19:26:26 1994
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From: David Holcomb 
To: holcomb@halcyon.com
Date: Tue, 13 Dec 94 19:22:21 -0400 
Subject: FW: (fwd) Re: Typical Failures of Early Williams Games
Status: OR

Newsgroups: rec.games.video.arcade.collecting
From: rls@cbnewsc.cb.att.com (richard.l.schieve)
Subject: Re: Typical Failures of Early Williams Games
Date: Wed, 23 Feb 1994 15:15:06 GMT
Keywords: Another old posting of mine.

In article , 
astrachan@austlcm.sps.mot.com ('paul astrachan/xvt3') writes:
>
> I have been thinking about converting a Stargate to a Sinistar.
> The following are two posts with a little conflicting info.
> Can we sort this out?
>
> From RLS
> >Todays Tech Tip ;-) is on the early William's games, Defender,
> >Joust, Robotron, Stargate, Sinistar, and Bubbles.  These game all
> >share the same basic logic board arrangement as follows:
> >
> >-------------------    ------------          ------------  -------
> >|                 |    |          |          |          |  |     |
> >|                 |    |          |          |          |  | AUX |
> >|   CPU/VIDEO     |    | ROM/PIA  |          |  SOUND   |  | SND |
> >|                 |    |          |          |          |  |     |
> >|                 |    |          |          |          |  |     |
> >|                 |    ------------          ------------  -------
> >|                 |
> >|                 |    ----------
> >|                 |    |        |
> >|                 |    |        | <--INPUT
> >|                 |    ----------
> >|                 |
> >-------------------
> >
> >The three boards on the left are often mounted on a metal plate.
> >The sound board is the same one used in pins and the AUX SND board
> >is only used in Sinistar.
>
>
> From Gregg W.
> >Sinistar uses a different ROM board and interface board than the rest
> >of the games do and requires an extra board that none of the others
> >had for speech (and the sit-down game has a second sound board).  It
> >also uses a special zillion (48?) directional joystick for input.
>
> Both posts indicate the CPU/Video is the same.  Is the ROM/PIA board
> different from the Joust/Robotron ROM board?

I said: "These game all share the same basic logic board arrangement"
                                                         ^^^^^^^^^^^
not the same logic boards.

Sinistar does not use the same CPU/Video or interface boards as
Robotron/Joust.

> Is the Interface board different?
>
> Is the Speech board the same as the aux board that was used on Williams
> Pinball games like Alien Poker (I have an AP speech board)

Yes.

> What was the point of the second sound board on the sit down version.
> Stereo effects?

Yes, for Stereo.  Kind of a reverberation effect.


				Rick Schieve
				rls@intgp1.att.com
				


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From: David Holcomb 
To: holcomb@halcyon.com
Date: Tue, 13 Dec 94 19:23:07 -0400 
Subject: FW: (fwd) Re: Typical Failures of Early Williams Games
Status: OR

From: woodcock@crchh75b.bnr.ca (Gregg Woodcock)
Newsgroups: rec.games.video.arcade.collecting
Subject: Re: Typical Failures of Early Williams Games
Date: 23 Feb 1994 04:16:35 GMT

'paul astrachan/xvt3' (astrachan@austlcm.sps.mot.com) wrote:

> I have been thinking about converting a Stargate to a Sinistar.
> The following are two posts with a little conflicting info.
> Can we sort this out?

> From RLS
> >Todays Tech Tip ;-) is on the early William's games, Defender,
> >Joust, Robotron, Stargate, Sinistar, and Bubbles.  These game all
> >share the same basic logic board arrangement as follows:
> >
> >-------------------    ------------          ------------  -------
> >|                 |    |          |          |          |  |     |
> >|                 |    |          |          |          |  | AUX |
> >|   CPU/VIDEO     |    | ROM/PIA  |          |  SOUND   |  | SND |
> >|                 |    |          |          |          |  |     |
> >|                 |    |          |          |          |  |     |
> >|                 |    ------------          ------------  -------
> >|                 |
> >|                 |    ----------
> >|                 |    |        |
> >|                 |    |        | <--INPUT
> >|                 |    ----------
> >|                 |
> >-------------------
> >
> >The three boards on the left are often mounted on a metal plate.
> >The sound board is the same one used in pins and the AUX SND board
> >is only used in Sinistar.


> From Gregg W.
> >Sinistar uses a different ROM board and interface board than the rest
> >of the games do and requires an extra board that none of the others
> >had for speech (and the sit-down game has a second sound board).  It
> >also uses a special zillion (48?) directional joystick for input.

I am speaking from the perspective of the sit-down version which I
have right next to me and I can assure you that all sit-downs I have
ever seen have had the different ROM and interface boards.  I
*suppose* that the stand-up version be different (the same as the
other games) but I very much doubt it.  I am pretty sure that the
reason the interface board is different is because it had to
accomodate *48* different input signals which is highly unusual.  This
is why I said it would be better to start with a Sinistar and go
backwards because you MIGHT be able to put the other games on the
Sinistar ROM/interface boards (but I haven't looked into it).  I KNOW
that both versions of Sinistar use the same joystick but as I never
paid attention to the stand-ups that passed through my hands, I cannot
say FOR SURE that the ROM and interface boards are the same as the
sit-down.

> Both posts indicate the CPU/Video is the same.  Is the ROM/PIA board
> different from the Joust/Robotron ROM board?

Yes.

> Is the Interface board different?

Yes.

> Is the Speech board the same as the aux board that was used on Williams
> Pinball games like Alien Poker (I have an AP speech board)

Probably but can't say for sure (I bet Rick can).

> What was the point of the second sound board on the sit down version.
> Stereo effects?

YOU GOT IT BABY!!!!!YBAB TI TOG UOY


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Subject: FW: (fwd) Re: Typical Failures of Early Williams Games
Status: OR

From: woodcock@crchh75b.bnr.ca (Gregg Woodcock)
Newsgroups: rec.games.video.arcade.collecting
Subject: Re: Typical Failures of Early Williams Games
Date: 24 Feb 1994 02:19:13 GMT

richard.l.schieve (rls@cbnewsc.cb.att.com) wrote:
> Sinistar does not use the same CPU/Video or interface boards as
> Robotron/Joust.

In my experience (3 upright, 2 sit-down), this is false.  CPU/video
boards have always been compatible for me but your mileage may vary.
I concur about the interface boards, though.