Save our High Scores - The Project

What's New

Jan 28th 2007

Mr.Do's Castle high-score saver !   Patches and details for the 3 different versions of the game. 
Follow the link for details High Score Saver for Mr. Do's Castle !

Updated the EAROM install guides Installing the EAROM replacement on DigDug, Centipede and Millipede

Apr 6th 2005

This page needs revamped badly...   In the meantime while I think about what to do..... Gottlieb Reactor High Score saver !  There's not a proper Page 
for this yet even though I did the patch a long time ago (!)  Here's the stuff + docs.  Reactor High Score Save patches  
I still wonder what I did with the Skykid high-score saver ?!?!?

Mar 20th 2005

No updates in a while eh ? Added pages for the new score saving kits for Xevious and Bosconian. These are plug in boards
that fit into the CPU socket, they add an EEPROM for saving the scores too and a couple of additional features.

Xevious also add a new Freeplay option and keeps the attract screen going even when coined up.
Bosconian is available and also keeps the attract mode going even coined (!)

Bosconian Score Saver Kit - Install guide

Xevious Score Saver_Kit -Install guide

Aug 15th 2001     LOTS !!!

So I actually finished the pages !!  These hacks have been hanging around since the end of Feb. waiting to be documented, but I think they're worth the wait.   Eventually... I'll update this page so it's not quite so sad looking.

Super PacMan               - The Save !

Donkey Kong                - Installation Details + Theory of operation & Source Code

Donkey Kong Junior.  - Installation Details + Theory of operation & Source Code

Feb 12th 2001    PENGO 

This is a patch I never quite got around to doing, but here are full details and pics of the upgrade. As the board uses standard 2k x 8 SRAM,  it's pretty simple to replace with a non-volatile memory. Also as there's a lot of unused RAM in the game there's plenty of space for the saveing the high-score table.

The source code for the update is also available along with notes on the ROM patches made to support the additional code. Click here for the page  Pengo High Score Save.

Feb 11th 2001    FROGGER updated !!

This is a reworking of the high-score hack I did for frogger a while back, it adds the ability to enter initials when you get a highscore and saves the high-score table to battery backed RAM, if it's present. 

The initials input doesn't require the RAM to be added, the high-score table will just be reset when the machine is powered up.

Click for the "GC" Frogger High Score Save & Initials Enhancement .

June 1st    '99    Q*Bert  Battery Replacement

Bah... made a error on the page ! The CORRECT part number for the RAM is DS1220 NOT DS1225

This is an upgrade I did AGES ago but never got around to documenting, as Q*Bert fans know the board contains a small battery to power the two RAMs which contain the high-score information. However, this battery is prone to leaking which can ruin part of the board. I decided to remove the battery and replace it with two battery backed RAMs that are extremely unlikely to leak and offer a life span of a minimum to 10 years. That'll keep your board & scores alive for a while.

Click for details Q*Bert Battery Replacement Page


May 29th   '99    Dig Dug EAROM replacement

Wow !! I've not done anything about this for AGES.... So time for a quick update.

By default Dig Dug will save high scores, however, to do this it used an EAROM, ( Electronically Alter Read Only Memory, I guess these were a pre-cursor to EEPROMs ??) anyway.. these parts required -29 volts to alter their contents and, worst of all, they're really hard to find these days. So a plan was formed to build a modern replacement, lacking datasheets and only having an overview of how thing worked and board schematics I started to build a prototype replacement.....

Pics of the proto-board are here, it was pretty special...

Click for the pics Dig Dug EAROM replacement board.

Current status is that the board is being tested with some of the other Atari games which used the ER-2055 EAROM. Hopefully I've duplicated the ER-2055 'sufficiently' so it'll work as a straight drop in replacement as with Dig Dug.

The other BIG advantage of this board is that is DOES NOT need the -29v supply, it runs of a regular 5v single supply. This is great if you have a JAMMAtized dig dug boardset, it'll allow the scores to be saved !

More will follow SOON !!

Aug 17th    Gaplus  

ROMs and details now available, I've also added a save to Galaga 3 but I'm unsure as to exactly which RAM on the midway boardset is the one to replace with a battery backed SRAM. Hopefully I can get this figured out soon.

July 31st     Mappy     

The page & ROMs are now available.
Skykid update almost complete and I should have this up over the weekend, Gaplus has just been added to the list too !
So lookout for that hack soon (ish).

July 22nd    Bombjack

I've just add the pages showing how to get Bombjack to save it's scores..

Please note: The battery backed Static RAM's used are  DS1220 and M48Z02.

Background & Technical Details

This whole thing started after a discussion, on and later with James Hagen, about the possibilities of making Galaga save the high scores after power off, if you've ever played for hours on a favorite game and achieved an all time personal best, then you'll understand how much of a loss it is to turn the machine off (like the first time I cracked half a million on Galaga).

So after disassembling the Galaga ROMs, and a few code hacks to the original game code, it was modified to not clear the high-score on power up, unless it was blank. The next stage was to ensure that the RAM used to store the score kept its contents even after power off, here low-power battery backed SRAM ( static RAM ) comes is VERY useful. However, Galaga uses 1k x 4 - 18pin RAMs and the smallest battery backed RAM is a 24pin 2k x 8, therefore a small adaptor board needed to be built which would then plug into the two RAM sockets on the Galaga video board.

Another possible technique was to source a couple of very low power 2114 compatible static RAMs, like the Harris 5114 - now these really are low power about 25uA @ 2v to retain their memory, you'd then need to add either a battery backed SRAM controller or build a small circuit to control the 'Chip Select' ( so that during power on/power off spurious writes to the RAM didn't corrupt it ). There'd also need to be a battery to supply back up power.

After some experimentation all-in-one SRAM approach was adopted as, overall, it's a much cleaner solution.

Once Galaga was patched this lead onto the next game, which for no better reason that James H. suggested it first, was Mr. Do, this proved to be much easier than Galaga, and only hardware modification was the addition of a socket for the RAM chip.

Now I'm on a roll an it's time to add 'save' to EVERYTHING... Well perhaps not everything but a 'few' favorites that could really do with it.


The Story so far...

- Battery replacement
- EAROM replacement
- Program images and details of installation
Mr Do
- Full details and modified program ROMs are available now.
- Program  images and details of installation
- Program  images and details of installation
- Pictures of the plug in RAM board 
Super PacMan
-Program  images and details of installation 
Donkey Kong
- Theory of operation, code updates and installation details
Donkey Kong Jr.
- Theory of operation, code updates and installation details
-Plug in ROM & EEPROM board
-Plug in ROM & EEPROM board
- Program images + needs a NVRAM
Mr Do's Castle
Program image + Source code

Information, Pictures & Game Patches...

Galaga Save High Score Project - Screen Images of the PCB board mapimg.jpg (5646 bytes) Mappy Save High Score - ROM images & details
Mr.Do Save High Score & Screen Flip - Details & Program Mod's Gaplus Gaplus Save High Score - ROM images & details
bombjack.gif (6112 bytes) Bombjack Save High Score - ROM images & modification details Dig Dug Dig Dug EAROM replacement board
Q*Bert upgrade Q*Bert battery replacement frog.gif (2892 bytes) Frogger High Score Save and Initials Enhancement 
Pengo High Score Save

Instructions & Source Code

Xevious Score Saver + Freeplay

Installation Instructions for the Kit
Bosconian Score Saver

Install instructions for the kit


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