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brizzo

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One of the ways that I give back to the arcade community is volunteering my time and expertise to a group known as The Dumping Union. It is a great group of people who collaborate to find and preserve video games, mainly arcade games. We have many eyes constantly looking for new game versions, prototypes, unreleased games, unique hardware, etc.

On June 25, our friend farzeno spotted an unusual version of Bubble Bobble on eBay in Germany.

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He made the immediate unilateral decision to purchase this gem, and secured it for all arcade collectors. Another amazing component of The Dumping Union is the generous financial donators who have since helped farzeno recoup some of the purchase cost.

Let's talk about this board set! First point of interest: this is not a Bubble Bobble pcb!? This is Bubble Bobble software running on Tokio pcb?! This board set does not have any protection chips, not even the one normally used by Tokio (Motorola 68705 MCU). As some of you know, it took many years to finally achieve accurate emulation of Bubble Bobble due to the protection chip/mcu.

Why is this pcb in a cage and covered in epoxy? Our best theory it was a location test board, to get feedback on the game. It was not unusual back then for cabinets to be targets of theft with game boards being stolen. Epoxy was just another lay of security.

In the past, other pcbs from Taito have been found just like this one. http://www.jammaplus.co.uk/forum/forum_posts.asp?TID=54642


Once I start processing this pcb to extract the roms and their contents, I am going to share some photos and story to the work involved on this thread :D
 

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We discussed within The Dumping Union what the best method to extract the game code from eproms. The original plan was to hijack the Z80 cpu data/address bus from the bottom of the pcb, and electronically read the contents without having to physically remove the epoxy and eproms from the pcb. (This task was volunteered to be done by Phil B)

When farzeno received the package, he found this problem:

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Taito was very serious about trying to deter bootleggers back in the day!! Finding epoxy coated on both sides of the CPU board presents a very serious challenge!

My intended plan is to use a chemical method to soften the epoxy only in the areas covering eproms. They appear to be in sockets, which will hopefully make this easier.

Board just arrived as I'm typing this, will post more as I proceed

:thumbsup: :thumbsup: :thumbsup:
 
That epoxy looks nasty. Hope you're able to soften it up and remove it safely.
 
Just playing the game, are you able to notice any obvious differences from the original release?
-ud
 
Just playing the game, are you able to notice any obvious differences from the original release?
-ud

Perhaps tonight or tomorrow I will have some time to try playing it, but here are some comments from farzeno when he was testing:

graphics roms checksum are different from current set. Seem like some sprites are different

The game works.
Significant change is the intro is missing (the one with the 2 characters and bubble around them.)

The levels seem to be identical but i am not going very far. Level 10/15. The board seem to be unstable after some time of use. I noted some graphic RAM to be hot after some time of use. Hopefully they are socketed, but didn't have spare to see if it's the problem.

Still no sound but i think it's the amp IC who is dead. No sound when touching it.
 
damn !! not taking any chances indeed!!

ok I must admit I *LOVE* seeing this stuff!! thanks !!!
 
8o I'm in love in front of such beauty <3

Good job, keep us dreaming...
 
Amazing work guys!

Can you post a link to the dumping union donation page? I'd like to send some dollars their way :thumbup:
 
I suppose there are many open communities that work together to further certain causes, but being into games, I really appreciate all the work that goes into preserving gaming history, from simple dumps to crazy reverse engineering of old hardware. I've sourced a few dumps that are currently in MAME, but nothing on the scale of guys like Shou, System11, etc.
-ud
 
Big thumbs up to the entire dumping union! Tons of great stuff from these guys.
 
Hello,

Brizzo, congratulation for your finding ! priceless !

May i suggest one method to try to soften the epoxy coating ? The product it is called "Decanol" in my country, and it is a gel-liquid that is used to dissolve/remove old paint from any substrate. heres the info, also pdf : http://arhitectural.policolor.ro/ro/produse/grunduri-si-diluanti/decanol-super
I have used it and it is good for removing may kinds of paint, submerge the object to be cleaned in this solvent and let it stay for a few hours, clean, repeat.This product i have not tested on the PCB green coating, pergaps it is a good ideea to apply it only on the epoxy coating.
Also may i suggest a hot air gun, at a low-ish temp setting ?

Good luck in your quest to retrieve the data on the eproms ! Dragos.
 
Had some time today to build a taito classic to jamma harness. As farzeno explained, the board seems to have issues. Keeps resetting with no specific pattern at different times. Also crashed and locked up while playing too. One of the program z80s felt hot through the epoxy. No sound output for me either.

Figured I would try poking at the epoxy tonight and see what we are dealing with. This stuff is hard and dense. The top board weighs probably 1.2kg or more. Almost all types of epoxy lose strength when heated. Decided to go with using hot air station @ 250C and poked at the audio z80. After preheating area then concentrating on z80 it came off like hardened old rubber. Went to work getting the sound eprom out with some clay tools with good shape for picking. The material as it gets thicker and between the chips is much more challenging to remove. After 30-40 minutes of careful heating and digging the sound eprom has been extracted.

Digital archeology :thumbsup:

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