Congo Bongo HS Kit 3-boardset Installation Guide
Step 0: Turn off power to the game
While it may be possible to install this kit without removing your
board from its cabinet, you may find it easier to install
the kit if you do remove the board.
In that case, pay careful attention (or label), any wire
connections as you disconnect your board so that you can
correctly rehookup the game PCB afterwards.
Take note of which side of the PCB edge connector is facing the
parts side of the board and which side faces the solder side,
This connector is typically not keyed and can be
inadvertantly plugged in backwards - ouch!
It is recommended that you label the connector faces
with something like "parts side" or "solder side".
Step 1a: Locate the CPU/Controller board
This boardset consists of three boards (video, CPU/conroller, and sound).
The CPU/Controller board is the larger pcb which is between the
video and sound pcbs.
It has 834-5166 on the PCB.
It is the board with the edge connector for the main harness.
Congo Bongo CPU/Controller board (834-5166)
Step 1b: Locate the Sound board
The sound board is the smaller board on the top of the boardset.
It has 834-5168 on it, and is also labelled
"Tip Top - SOUND".
It has a single gray ribbon cable connected to it and is attached
with 4 or 5 plastic standoffs.
Congo Bongo Sound Boards (834-5168)
The sound board will need to be temporarily removed in order to expose the
CPU Z80 processor such that the HS kit can be installed.
Congo Bongo Sound temporarily removed exposing Z80
Step 2: Remove the Z80-CPU chip
Locate and remove the Z80 chip on the CPU board.
Use the above photos to assist in locating it.
See Z80 Chip Identification
for additional information.
The Z80-CPU chip is a 40 pin (large) chip, located at U4
Do not get this chip confused with the other 40 pin chip nearby.
Remove the chip gently by using a flat head screwdriver
to pry it out of its socket from each end.
Be careful not to bend any of the pins.
If any pins do get inadvertantly bent, you will need to straighten
them out before the next step.
Needle nose pliers work the best for this.
Congo Bongo Z80-CPU location
Step 3: Insert the Z80-CPU into the daughter card
Insert the just removed Z80-CPU chip into the empty 40 pin
socket on the High Score Save Kit.
Make sure pin-1 is correctly oriented.
Pin-1 is marked on the Z80-CPU chip usually by some type of indentation
or circle molded into the plastic.
The end of the chip with the marking, needs to match up with the
socket on the daughter card that also has a marking on the plastic.
Pin-1 is also labelled on the kit pcb with a "1".
Click images for a larger view
Z80 CPU Chip
High Score Daughter Card
Step 5a: Insert the daughter card into the CPU board
Insert the daughter card back into the Z80-CPU socket on the
CPU board where the Z80-CPU chip was originally removed from.
Again, make sure pin-1 of the Z80/daughter card is oriented
to correctly match pin-1 on the CPU board.
Use the photos as a guide.
The header on the daughter board has pins that are more
heavy duty than the original Z80-CPU pins, thus you will need
to press very firmly to get the daughter card to be fully
inserted into the original Z80-CPU socket.
Congo Bongo with HS kit installed
Step 5b: Secure the sound board to the CPU board
Unfornately once the HS kit is installed, there is not enough
clearance between the sound board and the CPU board to use the
same standoffs as before.
You will need to figure out another way to securely attach
the sound board to the cpu board.
Possibly by using longer plastic standoffs or attaching the
board in a different way such that it is not likeky to move
around too much or cause any electrical shorts between them.
Not enough clearance to reuse the same standoffs
Step 6: Double check your work
Review the steps and double check that Z80-CPU is properly
installed into the daughter card with no bent pins and that
it is correctly oriented for pin-1.
And that the daughter card is also installed snug into the
Z80-CPU socket at U4 with pin-1 matched up.
Step 7: Powerup and game and enjoy!
Reinstall your board into the cabinet if necessary, and then
powerup your game.
If the game does not come up, turn power off immediately,
double check your work, and read over the
trouble shooting section.
Step 8: Optionally remove the four CPU code eproms
The four CPU code eproms are not needed once this kit is installed
because all of the software is contained on the single eprom as
part of the kit.
These four code eproms can be removed and used for other purposes.
As well it saves a tiny amount of power and heat.
This an an optional step and can be skipped.
Congo Bongo CPU eproms can optionally be removed.