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April 3, 2020 Haze Categories: General News. Comments Off on Under the Surface (part 5)

I’ve now set up a PayPal account linked to “plugandmame@outlook.com” so if anybody wants to contribute towards the purchase (and shipping to Sean / TeamEurope) of Plug and Play devices, then that address can be used. It will help enormously with sourcing additional units, plus any spares we might need for experiments (sometimes dumping is not straightforward as many of these don’t use regular ROMs, but ROM globs)

As these are donations, not payments for any specific guaranteed product or service, be sure to send them as gifts. Also don’t send email to that address, it won’t be checked. If you want to discuss sending a specific unit you already own instead, please tag on on Twitter.


One of the big licenses JAKKS got hold of was one to bring the original Mortal Kombat home once again. The JAKKS Mortal Kombat is a fresh port of the game to SunPlus hardware, and as such is different to the other ports. Two different units existed for this, one with fatalities and blood, and the other without, although the difference between them appears to be a configuration jumper inside the device, not a different ROM.

The game tries to stick to the arcade source material, although obviously some cuts have been made to work with the SunPlus hardware. This one is also unusual in that it has some additional RAM as well as ROM for decompression of character graphics etc. This means that during the Endurance matches there is some loading when the character swaps in, although the Shang Tsung fight does not do this (presumably because it doesn’t have to load in a full moveset for each character?) I do wonder if it wouldn’t have been possible to decompress assets on the fly to avoid this altogether, but it’s possible the SunPlus was slightly too slow for this.

One thing of note, various external sources say this should be a 6MByte ROM, but no matter what was tried we could only get a 4MByte dump. I’ve completed the game and not observed any accesses beyond the 4MByte mark, even if the end of the ROM isn’t filled as you’d expect for unused space. Furthermore there’s a bytesum type checksum in the header that the data we have falls short of. I’m not really sure what happened, maybe it was deemed the data past 4MBytes was unused by the game and it got chopped, as it didn’t seem to be in the device. There’s a remote possibility that it’s missing and used for the (unemulated) 2 player mode, that required you to link 2 units, but I’m not sure what that would require a whole extra 2MByte of ROM either. It would be nice to get to the bottom of this mystery one day. There is one odd thing with the emulation and that is from a cold boot it does take quite a few playthroughs before the attract demo randomizes properly, otherwise it’s Cage vs. Cage.

Mortal Kombat was hugely influential on the video game industry, and this 2004 port represents part of its legacy, having it emulated helps document that.


Mortal Kombat Mortal Kombat Mortal Kombat
Mortal Kombat Mortal Kombat Mortal Kombat
Mortal Kombat Mortal Kombat Mortal Kombat
Mortal Kombat Mortal Kombat Mortal Kombat

I mentioned it in the 1942 fix coverage, specifically because this unit exhibits the same issue as the older incorrect emulation, but another big license for JAKKS was the one from Capcom, securing the rights to bring 1942, Commando and Ghosts’n Goblins home around 20 years after their original release. For some reason this one wasn’t widely distributed in the US, but is very common in Europe and it’s a good set of ports for the most part, only really let down by some below average sound. It’s a real shame the promised MegaMan GameKey never materialized for it. These games are just as tough as they ever were.


JAKKS Capcom JAKKS Capcom JAKKS Capcom
JAKKS Capcom JAKKS Capcom JAKKS Capcom
JAKKS Capcom JAKKS Capcom JAKKS Capcom
JAKKS Capcom JAKKS Capcom JAKKS Capcom

An even bigger license for JAKKS was the Namco Ms. Pac-Man one, a notoriously difficult license to get hold of, and one that for the time good use was made of. Again I’m going to recap here by showing the 3 things related to this that were dumped last year. First there was the 5-in-1 GameKeyReady base unit, with a date of “07 FEB 2005 A SKU F” then there were the 2 GameKeys a 3 game one, and a 2 game one. The 3 game key had the newest date “11 JUL 2005 A SKU I” and actually contains an exclusive version of the original Rally-X, not found in SunPlus form on any other JAKKS unit. The 2nd GameKey was dated “01 APR 2005 A SKU G”

It is thought that the key with Rally X is from the point where JAKKS started bundling 2 keys with a base unit, and the base unit is from around the same time. We know there are earlier, undumped versions of the base unit, even ones that did not support high score saving.


JAKKS Ms. Pac-Man JAKKS Ms. Pac-Man JAKKS Ms. Pac-Man
JAKKS Ms. Pac-Man JAKKS Ms. Pac-Man JAKKS Ms. Pac-Man

Anyway, fast forward to this year, and we have 2 new dumps. The first of these dumps is the remaining 2 game GameKey, dated “01 APR 2005 A SKU G” the same day as the other 2 game GameKey this is likely the original pre-bundle version of the key. It lacks Rally-X and is therefore less interesting to own, but it has become overshadowed by the more common bundled key and as such is often actually the most expensive of the keys to pick up (if you just want to play the games on real hardware get the 3 game key instead, it’s cheaper and you get an exclusive game)

The 2nd unit dumped in recent weeks is the Wireless version of the Ms. Pac-Man. This one is actually a 7-in-1 and has 2 games “New Rally X” and “Bosconian” that would later be found on the GameKeys. The Wireless unit does not support GameKeys, and actually predates them, with a build date of “18 AUG 2004 A” on the ROM. It does support high score saving, so the version without that is likely an earlier build still. The actual unit here looks significantly different to the regular JAKKS Ms. Pac-Man unit, but there was another version of the 7-in-1 with the usual design, aside from a silver overlay on the panel. The silver overlay version was sold exclusively by QVC, and while that one has been sourced, it hasn’t yet been dumped.

I don’t think I need to show what these classic games look like as you’ve likely seen enough images of them already, but showing how the gaps are slowly being filled in, and how we’re slowly building up a picture of the different SunPlus based JAKKS licensed units seemed worthwhile. It’s just a shame the earlier pre-SunPlus Namco units look like they might require very specialized work to have any hope of dumping, all the code is in the CPU glob from what we can tell.


JAKKS Ms. Pac-Man JAKKS Ms. Pac-Man
JAKKS Ms. Pac-Man JAKKS Ms. Pac-Man

Some of the dumped from last year have seen recent progress too. While sticking with JAKKS, some work from Ryan Holtz fixed up some issues with the Care Bears game, allowing you to progress into the game. We’re back to ‘edutainment’ with this one, but with higher production values than the Sharp Cookie units, and an actual analog joystick, so that inputs feel more spongy and kid-friendly like the V.Tech consoles. This required ‘end of sample’ interrupts to be implemented, as well as an opcode that hadn’t been used anywhere else. It makes me think the code for that part of the game might have been handwritten SunPlus assembly, as the opcode in question doesn’t seem to appear in any other generated code.


JAKKS Care Bears JAKKS Care Bears JAKKS Care Bears
JAKKS Care Bears JAKKS Care Bears JAKKS Care Bears

Likewise the lockups in the ‘Light Tag’ part of the Winnie the Pooh plug and play were fixed (or at least made MUCH less infrequent, to the point it’s plausible maybe it would happen from time to time on hardware)


JAKKS Winnie the Pooh JAKKS Winnie the Pooh JAKKS Winnie the Pooh
JAKKS Winnie the Pooh JAKKS Winnie the Pooh JAKKS Winnie the Pooh

I think I’ll wrap up part 5 with that, having covered some of the more ‘already visible’ progress this time. Still, it’s possible some of these slipped by you, or the additional details provided here have been of interest, so it doesn’t feel like a waste of time covering them, and it gives more balance to the coverage than only looking at the uglier side of things.

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