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MAME work and other stuff

Your Shark is on Fire

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.

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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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I didn’t know I had permission to murder and to maim

December 5, 2016 Haze Categories: General News. 25 Comments on I didn’t know I had permission to murder and to maim

So… we’re approaching the end of 2016. I haven’t even started a 2016 write-up article, but for the sake of continuing tradition I probably should do one. The problem is, as I’ve been mostly inactive this year, I haven’t even really been following progress. Considering I usually start writing it a month or two before now, and don’t usually have something I’m happy with until a few months into the new year I’m definitely behind schedule with that.

I’m not sure there are even many people viewing these pages, but let’s see anyway because Crowdsourcing could help here. What happened in 2016 that needs covering? Anything done in MAME, not just arcade bits, that you feel has improved the project. Write as much of little as you like, try not to cover things other people have already covered unless you feel they neglected to mention something important about them. If there is enough of a response I’ll try and piece things together.

(yeah, there’s a 3rd part to the Magnet system writeup to do too, but I got stuck with the ADPCM playback and a bit burnt out with it so ended up putting it on the backburner for a while)

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