We are proud to announce the availability of
with High Score Save and Diagnostics
High Score kit features
The standard high score save upgrade that permanently remembers the top 5 scores and initials for both Donkey Kong and Donkey Kong Junior. Plus many extras features such as deluxe Freeplay, attract mode sound, powerup Selftest, and on-screen Settings.
This is a slightly modified version of the original DK high score save kit. It is altered to contain the Double Donkey Kong code and to save scores for both games. It also allows individual settings for each game.
Pricing and Availability
Price for upgrading your working DK jr. PCB is $160 plus return shipping. Return shipping is $25. Occasionally, I have already completed boards for sale at $260 plus shipping. Please email us for availability.
How do I get my board upgraded?
You send in your working Nintendo Donkey Kong Junior 2-board set and it will be upgraded or swapped for a "Double Donkey Kong with High Score kit" and shipped back. See board checklist below to make sure you have a compatible board for the modification. See shipping and packing instructions below.
Please make sure the board you are sending meets all of these checklist items. If not, email me, as I might be interested in purchasing your incompatible boardset, or applying it towards the purchase price of an already completed double donkey kong boardset.
Shipping your board
When packing your board for shipment, please be static aware (i.e. no plastic bags), bubble wrap is OK. The most common thing that breaks during shipment is the video adjustment pots, anything that can be done to protect those will help. If you remove the heavy metal mounting plate (if it has one), the boardset will fit into a (free) standard USPS priority mail shipping box, as well will save you money on shipping in both directions. If you do send in your boardset without the metal mounting plate, be sure to put something between them so they do not rub together during shipping and cause damage to the boardset. A sheet of bubble wrap comes in handy here or a sheet of anti-static foam.
How long does the upgrade take?
You will be emailed after the board is tested with an estimate of when it is expected to be completed (shipped). Usual turn around is 7-10 days from when the board is received to when it is ready to ship back, if there are boards in stock that have been upgraded, turn around will be almost immediate. As a general rule, it takes about a week once the board is received to complete an upgrade. Depending on how many boards are in the queue there may be extra delay.
What happens when you get my board?
When a board is received, it is first thoroughly tested using a special diagnostic test fixture. It checks the CPU RAM, the video character RAM, the video sprite RAM, the DMA controller, the interrupt controller. It also verifies all 5 analog sound triggers, all 7 digital sound triggers, and all 14 background music songs. Both characters sets are tested, as well all 4 color palettes. Finally the flip screen and reset hardware are checked. Only if/when the board passes all these tests will the upgrade process be started.
What is involved in upgrading my board?
The upgrade involves making modifications to both the video and CPU boards. Most of the socketed components are removed and either replaced or re-used elsewhere on the board as part of the modification. A special daughter board is installed into chip location 7H that contains some custom logic. This daughter board has a movable jumper that can be used to configure the initial game that is selected at powerup. At anytime you can toggle between games by pressing both the P1-start button and P2-start button at the same time. The game will instantly reset and toggle to the other game. The new game will start when both the P1 and P2 buttons have been released. Since toggling requires a hard reset, any remaining credits are cleared. A second daughter board is installed where the CPU is normally located at location 7F on the CPU board. This second daughter board is the High Score Save and Diagnostics kit.
Some of the sounds in Donkey Kong mode are slightly different that the original sounds. The Donkey Kong walking and jumping sounds have a slightly higher pitch than the original game, and the pounding sound during the introduction of the game is slightly distorted. It is not easily noticeable unless you have an original DK board nearby to compare too. This is probably an artifact that the game is being played on DKjr hardware, and that each board has custom hardware to generate each of these sounds. Note, all of the Donkey Kong music is exactly the same as the original game and all of the Donkey Kong Jr music and sounds are exactly the same as the original. Just a slight variation in pitch for walking, jumping, and pounding when playing Donkey Kong.
You can listen to the difference between the stomping, walking and jumping sounds by clicking here. Special thanks to Michael Bosch of mbdesigns for recording the sounds for comparison.