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Document Title: [QBert Tech.html (html file)]

Q*Bert Pinouts, switches, and JAMMA conversion info

Pinouts, switches, and JAMMA conversion info for Q*Bert, plus sound fixes and general troubleshooting

Uses information publically posted by Rick Schieve (Richard.L.Schieve@lucent.com)
Add'l Info submitted by David Shuman (shu@caltech.edu, essayes@telerama.LM.com)

Q*Bert Pinouts

MLB = Main Logic Board
SB = Sound Board
-- = No Connection

Main Logic Board (MA-378)
60-contact edge connector (A1P1)

A	+5 VDC			1	GND
B	+5 VDC			2	GND
D	--			4	--
H	--			7	--
J	--			8	--
K	--			9	--
L	--			10	--
M	A6P1-2 (SB)		11	--
N	--			12	A6P1-4 (SB)
P	--			13	--
U	--			17	2P START
V	--			18	UP-LEFT
W	--			19	DOWN-RIGHT
X	--			20	DOWN-LEFT
Y	UP-RIGHT		21	--
Z	A6P1-8 (SB)		22	A6P1-9 (SB)
a	A6P1-11 (SB)		23	A6P1-12 (SB)
c	--			25	BLUE
e	HORIZ. SYNC		27	+11.5 VDC
f	+5 VDC			28	GND
h	+5 VDC			29	GND
j	+5 VDC			30	GND

*connects to one end of the knocker solenoid, which is wired in parallel 
with a 1N4004 diode.  The other end of the solenoid connects to +30 VDC, 
which also provides power to the audio amp.
**closed = game; open = test.
***normally open.

Sound/Speech Assembly (MA-216)
24-contact edge connector (A6P1), only one side of board has contacts.

A	--				1	+12 VDC REG.
B	--				2	A1P1-M (MLB)
C	--				3	-12 VDC
D	--				4	A1P1-12 (MLB)
E	--				5	+5 VDC
F	--				6	GND
J	--				8	A1P1-Z (MLB)
K	--				9	A1P1-22 (MLB)
L	--				10	+30 VDC REG.
M	--				11	A1P1-a (MLB)
N	--				12	A1P1-23 (MLB)n.

Q*Bert Dip Switches

Switch 1  Demo Mode *
  On      infinite lives
  Off     normal play

Switch 2  Attract Play
  On      no sound
  Off     sound

Switch 3  Normal/Free
  On      free play
  Off     normal play

Switch 4  Game Mode
  On      cocktail
  Off     upright

Switch 5  Not Used

Switch 6  Kicker
  On      kicker on
  Off     kicker off

Switch 7  Not Used

Switch 8  Not Used

*In demonstration mode, the player will have infinite lives and can 
progress through the rounds by hitting either start button.

I finally got Q*bert JAMMAtized and I thought I'd pass along how I got the job done.

For a bit of background I build various adapters to allow older board sets to match up to the JAMMA wiring scheme. It goes like this: Louis's Harness shop (1-800-365-1941) sells a little chunk of circuit board that allows you to mate 2 female 56 pin (JAMMA style) connectors together. The female connectors are available lots of places.

You plug the male piece of circuit board into the JAMMA connector in the game. Then plug the other 56 pin connector to the circuit board. Put whatever connectors you need on the boards you want to use. Connect wires as needed between the connectors on the game boards and the solder terminals of the 56 pin connector.

Once you have done a few it becomes fairly simple and some adapters are useful for many games.

Q*bert (GV103) requires a large Main Logic Board and a Sound Board about a quarter of the size of the Main Logic Board. I have original docs but found David Shuman's pinout info on wiretap very helpful and included a copy at the end of this.

On to the adapter. I'm not going to explain this in detail. I know many of you are programmers with minimal electronics skills but to walk those people through this connection by connection is more than I want to take on. What I'm providing here is pretty basic stuff and if you can't handle the electronics get someone to help you that can.

My goal was to make Q*bert plug into a JAMMA harness with as few modifications as possible. The first issue was that Q*bert puts out separate active high H and V syncs and JAMMA wants an active low composite sync. I experimented with several circuits but the one that seemed to work the best for the monitor that I was using was to first invert each sync (with a 74LS04) and then AND the separate syncs (with a 74LS08). Again, this is what worked best for the monitor I was using. Sometimes it's easier to abandon trying to combine the syncs and just connect the separate syncs directly.

The next issue was the +30 VDC required by the audio amp on the sound board. After looking over the schematics I determined that the only thing that uses the +30 is the final audio amp, U23, an LM379S. My solution to the fact that the LM379S needed +30 (not provided by JAMMA) was to simply not use the LM379S amp.

The following is a drawing of the 2 watt audio amp circuit I've used successfully for some time. B. G. Micro has the LM380s cheap. Franklin Bowen was nice enough to do the ascii art.

                                     |      | |
                                     |------| |----- GND
                                     |      | |
                                     |      C5
           C1                        |     +| |-
                                     |------| |-----GND
          +| |-                      |      | |
   Input---| |------+                |
           | |      |         |\     |
                    >       2 |  \   |               C3
               VR1 <  <-------+    \ | 14
                    >         | LM   \              +| |-   4-16ohm spkr
                   <          | 380N   \ ____________| |-------
                    |         |        / 8 out   |   | |
                    |         |      /           |
                    |         |    / | 7,3       >
                    |         |  /   |          <
                    |         |/     |           > R1
                    |                |          <
                    |                |           |
                    +----------------+       C4 ---
                                     |          ---
                                     |           |
                                     |           |

 C1=  50 uF 12v
 C2=  .1 uF 12v
 C3= 250 uF 12v
 C4=  .1 uF 12v
 C5=  20 uF 12v
 R1=    2.7 ohm
 VR1=   10k ohm
None of the values in this circuit are critical. Feel free to use up some misc.

To use this with the Q*bert adapter don't connect anything to the +30 VDC or the sound board audio output (pin 7). Instead wire up the amp just described with the output directly connected to the speaker. For the input of the separate amp, solder a wire on to the bottom of the sound board at pin 9 of U23 (the on board amp's input). Now, the external amp does all the work.

The other non-JAMMA power supply voltage required by Q*bert is -12 VDC. I suspect that you could get away with powering the -12 with the JAMMA -5 but didn't try it myself. Enough of the older games required -12 to make me supply that voltage with a separate supply and connector.

The last complication was caused by the fact that the joystick for Q*bert is rotated 45 degrees from the way a standard joystick is mounted. It is a standard 4-way stick, it's just turned 45 degrees. This is why the pinout info contains connections for things like "DOWN-RIGHT" on a single pin.

I didn't want to remount a stick so I took advantage of a suggestion by Mark Jenison (I mentioned your name Mark, are you happy now? :-) ) and used 4 "OR" gates on a single 74LS32 to make an 8-way standard joystick do the job without rotating its mounting. The wiring went like this:

  Joystick         Q*bert input

  up  ----1 \
              ---- 3--- up-left
  left ---2 /

  up -----4 \
              ---- 6--- up-right
  right --5 /

  down --10 \
              ---- 8--- down-left
  left -- 9 /

  down --12 \
              ---- 11-- down-right
  right -13 /
I also added 4.7K (again, a non-critical value) pull-up resistors between each joystick connection and +5. Normally the game board provides the pull-up resistor but here its needed at the joystick to pull the inputs high. The joystick contact closure brings the inputs low.

With this scheme 2 adjacent inputs going low when the joystick is moved to 45, 135, 225, or 315 degrees gives one low output in the direction required by Q*bert. I suspect the joystick is more difficult to use than if you really rotated a 4-way joystick but the game is definitely playable.

I know some of you will be disappointed but I didn't connect a cabinet knocker but you gotta make some hard decisions at times ;-)

Well, I hope you people found this interesting. Thanks to Mark Jenison who worked with me on the adapter and to Kevin Klopp (alias mowlawnman) for loaning me his working sound board to help me debug mine.

Q*Bert Bootleg Pinouts

Q*bert bootleg pinouts (single board PCB)

Submitted by Steven Prendergast (stevenp@sgi.net)

Pinouts for bootleg (single board PCB) Q*Bert (Gottlieb 1982)

    component side      solder side
    --------------      -----------
               GND   1  +5V
               GND   2  +5V
               GND   3  +5V
              +12V   4  +12V
        (-5V) -12V   5  (-5V) -12V
         AUDIO OUT   7
                     8  TEST MODE*
                     9  SELECT SW
          1P START  10  COIN 1
          2P START  11  COIN 2
        1P UP-LEFT  12  2P DOWN-LEFT
      1P DOWN-LEFT  14  2P UP-LEFT
         VIDEO RED  16  VIDEO SYNC
        VIDEO BLUE  17
       VIDEO GREEN  18
               GND  20  +5V
               GND  21  +5V
               GND  22  +5V	


Pinouts obtained from operator panel on my bootleg machine.
Your mileage may vary.

Q*Bert sound Repair

From: joey@gopher.science.wayne.edu (Joey Oravec)
Newsgroups: rec.games.video.arcade.collecting
Subject: Re: TECH: Q*Bert no sound
Date: 14 Jul 2000 02:27:46 GMT
Lines: 53

someotherguy (someotherguy@SPAM_SUCKSmediaone.net) wrote:
: Bob Roberts sells LM379's.  We fixed a Q*bert here with one.  There's
: also a hack to the original power supply to prevent blowing up the
: chip again, it's in an overvoltage situation by design, explaining the
: premature failures...just for grins I attached an extra heatsink to
: this one.

Ok. I assume you mean roys "swap the zener to +28" posting. Do people
always neglect what I write? There is bad engineering in that circuit and
going to +28 makes it worse. This does NOT explain the premature failures.

I told Roy before and he acknowledged it might be an issue. He's one
awesome guy, but I think he missed this important fact on his original
posting. Running that regulator at +28 causes MORE current to be shunted
to ground. They use the simplest regulator possible: a zener diode biasing
a transistor.

Correct me if I'm wrong since I've only had my hands on about 5-6 qberts
ever. But I noticed the trend that dead sound always had bad power. That
IC is rated just about fine for what's being input to it, +30 is just fine
for that chip. Don't get me wrong it's not a superb chip but there is a
larger problem.

The problem is that the regulator resistor and zener basically need to be
5watt. +36vDC is being regulated down to +30vDC. Bringing that zener down
to +28 causes yet more current to shunt to ground which is a bad idea. If
that zener goes then chances are good the chip could eat +36 (and die) and
then the transistor could get shorted (and die). More evidence? most power
boards are horribly charred beneath those components because current kills
on that regulator.  Already that zener at 30v5w runs VERY hot to the
touch, running more current at 28v5w only kills it faster! 

These PSU's were designed to last about 18 months for while the game was
popular, and then who cares. They were designed to be functional... That's
about it.

Not practical to test and prove chip reliability. But hey. I upgraded my
regulator and have had zero difficulty among 3 qberts needing Lm379s
replacement for 2 years. The others with dead sound were NOT dead amp
chips. I think that chip gets a worse rap than it deserves thanks to the
ugly regulator in the power supply and its nonavailability today.

Correct me if I'm wrong, I'd love somebody find a flaw in my logic and
keep my qbert's sound working forever. But I keep seeing this advice pop
up and keep giving it the smackdown. Maybe somebody can notice my post
next time they feel like advising the +28 modification, or else comment as
to why I'm wrong!

  O..O    Arcade machine collection:
 (----)        http://www.science.wayne.edu/~joey/arcade/
( >__< )  IRC - EFNet #rgvac: demigod2k
^^ ~~ ^^

Q*Bert Troubleshooting

Q*Bert Doesn't Power Up
Newsgroups: rec.games.video.arcade.collecting
Subject: Re: QBert doesn't power up
Date: Fri, 21 Apr 2000 06:40:34 GMT

Since you're getting no signs of power, and you are on a known good
outlet, the first thing to check is your fuses.  Get a multimeter
(don't rely on a visual inspection) and check continuity between the
blades of the fuse holders.  That rules out both the fuse and poor
contact at the holder.  Fuses are your most probable culprit here.

Once you've got that sorted out, and the machine powers up, keep your
fingers crossed that your power supply board and sound board are good!
These seem to be common failure items on Q*Bert.

Then, go to Chumblespuzz's homepage for more Q*Bert info:
http://members.home.net/chumblespuzz/ in the arcade section, he has a
page for Q*Bert that describes troubleshooting sound problems, and
also a preventative fix to keep from zapping the sound.

If you find you have a sound problem and need to replace the amp chip,
Bob Roberts has them for something like $10.

My friend BVC's Q*Bert was suffering from a bad P/S, sound board, and
monitor.  With the help of Eric Anderson (rebuilt the P/S),
Chumblespuzz (Eric used his info to mod the P/S), and Bob (supplied
the amp chip)...and.now that I've replaced the monitor, Q*Bert lives!