Star Tech Journal

20
STAR*TECH JOURNAL/OCTOBER 1982
Video Board - The video board, as the name implies, is responsible for
generating all display information. The principle section of the board consists of
six 6116 color RAMs , two RAMs dedicated to each of the 3 colors (blue, red
and green). The surrounding addressing and RAM output circuitry consists of
an incredibly large number of tri-state buffers, multiplexers, octal flip flops and
shift registers. The schematics identify 3 different color busses, an object video
bus, a code RAM address bus, a data bus, and a sync and "Q" bus, to name just
a few. There are more busses marked on these schematics than Trailways has
out on the nation's highways!
Hardware
Color RAMs
6116 (6)
Object RAMs
93422 (2)
Staging RAMs
2ll4 (2)
Note: All RAMs in sockets
CPU Board - The central processing unit includes the microprocessor and
36K of program memory and scratch-pad RAM. The memory decoding
circuitry and the sync circuit are also included on this board.
Hardware
Microprocessor
Z80 A
Program ROMs
2732EPROMs(9)
RAMs
2114 (2)
Control RAMs
6116 (2)
X-TAL
12 MHZ
ROM Board- The small board (3" x 7") mounted directly on top of the game
board is where all image RO Ms are located. With this board removed, the game
will play, but there will be no specific characters, only various colored blocks
moving on the screen.
Image ROMs
Hardware
2732 E PROM
As can be seen, there are many similarities in this 3-board set and the 3-
board set used in Midway's "Tron". The same processors, the breakdown of
circuits on each board, and many of the same memory chips are the principle
similarities. This may be helpful in understanding each system as well as
reducing the number of parts to be stocked for board repairs.
Connectors
There are three connectors mounted on the logic board. These include:
"G" - 44 pins, located on game board, keyed (pin 6) all game switch inputs,
video outputs to monitor, and the audio outputs.
"T" - 18 pins, located on game board, keyed (pin 7), only four wires on
connector; 2 for ground, 2 for +Svdc.
"H" - 12 pins mounted perpendicular ( to the other connectors) keyed (pin 10)
+12 volts in, +12 volts out to coin door, +5 volts and ground.
All of the connectors use machine crimped pins, not the cheap kind where
the wire is just forced between two sharp edges of a connector pin, which strips
the insulation and digs into the wire to make contact.
The game will function normally with the "T" connector completely
removed. (+5 volts also enters the "H" connector.) With the "H" connector
removed, there will be a good picture, but no audio and the coin switches and
lockout coils will be dead. (No + 12vdc with this connector removed.)
The filter board has 11 connectors mounted on it. These connectors are all
keyed and it probably never will be necessary to remove them. (Board or power
supply can be removed without touching the filter board.)
The connectors to interconnect the three logic boards are four 50-pin ribbon
cables. These are labeled "S" and "R" (game board to video board), and "Q"
and "P" (video board to CPU board).
Miscellaneous Irifo
Joystick - 8-way Wico. Monitor - Wells-Gardner, Model 19K4903. Slam
Switch- There is a normally open slam switch mounted on the coin door. When
this switch is closed, the monitor will read out "TILT" and all credits will be
lost including game in play.
System Audio
The game audio section is extremely basic and should pose no problems in
troubleshooting any failures which might develop. All sounds originate on the
game board (see board set). These sounds are all preamplified and summed
together for final amplification by the audio amplifier located directly on the
game board. The final amplified signal for the speaker exits the "G" connector
Pin 5 ( orange wire). The speaker ground (black wire) is connected to Pin E on
the "G" connector.
There are two volume controls; one for the master volume and one for the
background music. Both of these controls are located next to each other on the
game board. There is no external volume control.
Audio Preamps
Audio AMP
Master Volume Pot
Background Music Pot
Speaker
LM3900 (2)
MB3730
SOK
SOK
4 ohm(Round) Part No. 07-00083-001
Self Test/Options
The self-test capabilities of"Jungle King" are extremely limited, with the entire
procedure seeming like it was just added to say there is some kind of self-test
feature present in the game. There is no separate self-test switch. To place the
game in test, switch 6 of dip switch A must be put in the "on" position. With a
good board, this will result in a screen with a blue background with the message,
"RAM Test No RAM Failure" printed on it. Should no letters appear, the !Cs
14 and 56 on the CPU board should be checked. If the letters appear in strange
colors, then one or more oflCs 104 thru 109 on the video board may be bad. All
!Cs which this self-test procedure checks are 6116 RAMs (all in sockets).
Options - The option settings for "Jungle King" are all programmable by dip
switch settings located in the upper left-hand corner of the game (top) board.
There are three 8-position dip switches labeled "A", "B", and "C". Standard
options affecting coining, number of jungle kings and bonus points are all
available. Some options may appear to be vague or confusing (lost something in
Japanese to English translation for Manual). The option (Dip Switch A-Switch
7) identified in manual for screen inversion is marked "2-P" or "1-P". The
normal position is "2-P" (switch 7 off). With switch 7 in the on position, the
screen will be upside down for the first and second players. Don't confuse this
option for the cocktail table and upright switch setting. That is switch 8 ( on for
upright, off for cocktail table). There is also a "coinage" option (dip switch C-
switch 8) which offers a selection of either "2 ways" or" 1 way". The normal
position is "2 ways" (switch 8 off). With switch 8 on, only the right coin chute
will function. The left will be dead. There is also an option labeled "no hit of
player" (dip switch C-switch 7). This may be set at "normal" or "no hit". This
option if set to "no hit" (switch 7 on) is essentially a free play setting. With this
switch on and at least 1 credit on the game, play can continue indefinitely as
there is an unlimited number of jungle kings. This switch setting could also be
helpful in troubleshooting a board with a problem that appears only in a later
game frame.
*Please take note that a service switch ( credit but no coin meter advance) is
located on the coin door, and that the maximum number of credits is 9 (not an
option). No credits or coins will be registered above 9.
000
Conclusion
Early indications are that "Jungle King" will probably be a very reliable and
profitable machine. This is only based on early collections and the condition of
the new uncrated machines. These brand new machines should all work, but in
many cases there is a surprisingly high failure rate. This is not the case, however,
with "Jungle King". As of the first 100 machines uncrated, there was one
machine with a problem (board related - resistor lead shorting out 2 signals).
This is a high standard for any game, and usually is a good indicator of how well
the game will hold up in the field. Hopefully there won't be many problems with
the boards. Even though these boards have appeared in earlier games, which
always makes things easier, there still is only a very limited self test and very
little documentation. Any technician working on a "Jungle King" board set
won't have to worry about misplacing the Theory of Operations, Block
Diagrams, Memory Maps, or Timing Diagrams - there aren't any! The only
documentation provided is a manual on the monitor and the game manual itself.
The game manual includes some assembly drawings with illustrations and parts
lists. There is also complete board schematics and sections regarding routine
maintenance and game set up. Parts of the manual were copied from the "Qix"
manual. The power supply is the same for both games, so why not? Unfortunately,
a section of the "Qix" manual regarding the "CMOS RAM" and how to clear it
of garbled information has mistakenly been printed in the "Jungle King" manual
(page 4). This section should just be ignored. Don't bother looking for any
battery on a "Jungle King" board.
The overall game design of"Jungle King" makes it a hybrid, part American
(monitor and power supply), and part Japanese (board set). Hopefully this will
result in a game that is truly the "best of both worlds".
At the present time, there is no way of speeding up gameplay or increasing
the difficulty. However, by the time this article is published, Tai to will probably
have some sort of "speed-up" kit available through their distributors.