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MAME work and other stuff
December 22, 2016 Haze Categories: General News. 8 Comments on Your Shark is on Fire

There are 4 Toaplan games with no sound in MAME 0.180.

These games are Fire Shark, Vimana and Teki Paki and Ghox. The original Japanese release of Whoopee is lacking in sound too but in that case the Export version is not.

The reason these lack sound is simple, the chip shown below.


Each of the above games contains one of these chips. The chip is an MCU containing a Z(1)80 core and various peripherals as well as 16kb of internal ROM data. That ROM data contains all the sound information for the game, all the sound effects, all the music sequences, everything; it makes no use of external data.

Without the internal ROM for each game sound simply can’t be emulated properly, because there’s nothing to use to emulate it. Due to everything being squeezed into the internal ROM space there’s no exploit using external code / data that can be used to dump the roms either as was done for the NMK004 sound system and a number of others.

As a result, these have been considered ‘holy-grail’ targets by quite a large number of people. With that said, I present to you the following 3 videos.

Those videos are all showing proper emulation of the sound, not some ugly trick using samples from the PCB, but the actual sound code running in MAME, driving the emulated YM3812 sound chip.

This was made possible by the decapping work done by ‘Team Caps0ff’ who managed to acquire the various chips that had previously been sent for decapping, take stock, and resume work on them – identifying weaknesses and coming up with a solution, in this case clearing the security bit inside the chip and reading out the data. (They also provided the MCU hookups in the drivers meaning this ended up being a simple case of sitting back and enjoying the results)

Ghox and the Japanese Whoopee PCB using this chip have not been done yet because Caps0ff doesn’t currently have those chips, and has a backlog of other chips to process, but the method used to dump the ones you see is now proven and tested and will also work for those once they’ve been acquired.

The Caps0ff blog contains more detailed technical information on the process used, it’s a fascinating read and shows that these guys really know their stuff :-) Please check it out and show support if you can.

(and yes, this has been my favourite news of the year to wake up to, hence giving it a bit of coverage)


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Thanks Haze for writing this article and making the videos and of course special thanks to Team Caps0ff and everyone that assisted in making this wonderful progress possible.

That’s fucking fantastic!

“This was made possible by the decapping work done by ‘Team Caps0ff’ who managed to acquire the various chips that had previously been sent for decapping, take stock, and resume work on them”

ALL of the chips? I hope they’ve been taken care of after all this time.

There are some (19 of them?) that were not recovered but the vast majority were.
For the ones that weren’t I don’t think any of the MCUs are irreplaceable.

odd, everything has been kept up to date, wonder if it’s related to one of the other sites on here. “Detection ratio: 1 / 68” does indicate to me a likely false positive tho, although last time the site got infected it was rather sneaky and didn’t show up for the vast majority of users so probably one to keep an eye on.

Fantastic news :)) Thanks for Your work guys :))

Great news! Also, that’s some awesome Truxton-ish music in Fire Shark! :D

Maybe something similar to this technique can be used to extract the code from the Star Wars arcade chip?

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