Double Donkey Kong High Score Save Kit -- Installation Guide
Step 0: Turn off power to the game
It is recommended that you remove your boardset from the
cabinet before making the modifications as it requires
soldering one wire.
When removing the boardset, pay careful attention (or label),
any wire connections as you disconnect your board so that you
can correctly rehookup the game PCB afterwards.
If your board uses the large 44 pin edge connector, take
note of which side of the connector if 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 1: Locate the CPU board
This is the board which has the edge connector as well it
has the Double Donkey Kong sound daughter card.
Double Donkey Kong (Junior) CPU board
Step 2: Remove the Z80 CPU chip
Locate and remove the Z80 chip on the CPU board.
It is located a row/column 7C.
Remove the chip gently by using a flat head screwdriver
to pry it out of its socket from each end.
Becareful 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.
Step 3: Insert the Z80 into the daughter card
Insert the just removed Z80 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 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 4: Insert the daughter card into the CPU board
Insert the daughter card back into the Z80 socket on the
CPU board where the Z80 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 pins, thus you will need
to press very firmly to get the daughter card to be fully
inserted into the original Z80 socket.
Step 5: Solder the "select" wire
The lose wire that is attached to the DDK high score save
kits needs to be attached to the existing daisy-chain
"select" wire that interconnects all of the DDK eproms.
It can be attached anywhere in the chain.
I'm currently suggesting that it be connected to the
solder glob that is on eprom chip 5E.
Using your soldering iron, touch the connection at
5E to melt the glue, clean it off with a paper towel,
as well clean you soldering iron tip too.
Once the glue has been removed, wrap the lose wire
around the connection several times, and then
reflow the solder connection.
You might want to add a little extra solder.
It is also suggested that you glue or tape the wire
to the boardset so that it inadvertantly does not
get snagged or broken.
Step 6: Double check your work
Review the steps and double check that Z80 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 socket with pin-1 matched up.
Lastly, verify the select wire is attached.
Step 7: Powerup and game and enjoy!
Reinstall your board into the cabinet, and then
powerup your game.
You should immediately see the bootup
Verify the correct title "DOUBLE DONKEY KONG" is displayed at the top.
You will have 5 seconds to press P1 and enter
setup mode, or the
game will timeout and automatically transition to gameplay mode.
If the game does not come up, turn power off immediately,
double check your work, and read over the
trouble shooting section.