This is ... MADNESS! Super Neo MVS Converter Fixed with ZMC2!

[l_oliveira]

You are free to try to guess what is this.

The chip "pasted" on the board is a NEO-ZMC2 FYI.

[Trenton_net]

I assume by all the globs of solder and bridged pins that this is a botched job which doesn't work. (^_^);

Looks like someone just wanted to practice soldering on a board. But I have no idea where the donor came from.

[l_oliveira]

I assume by all the globs of solder and bridged pins that this is a botched job which doesn't work. (^_^);

Looks like someone just wanted to practice soldering on a board. But I have no idea where the donor came from.

You think I would bother posting if it didn't work ?

That's to replace the CPLD on the neoflash MVS > AES converter because it fails to convert the graphics correctly when the NEO-GEO uses the scale function on the graphics.

Edit: There's 32 lines connecting to the top slot (32 bit for graphics) and 16 lines (4 serial bit shift registers and signaling lines) connecting to the NEO AES.

To prevent these adapters from being made and to save connector pins on the AES SNK decided to make the graphics converter from parallel to serial (which is onboard on MVS) be part of the cartridge on the AES. The donor was a corroded MVS board who died a sad death to the corrosive fumes of a dirty and old wooden arcade cabinet.

[Calpis]

I recently released the true logic to the PRO-CT0 on the NG dev wiki, so you could have JTAGed the CPLD and fixed it that way instead.

[l_oliveira]

I recently released the true logic to the PRO-CT0 on the NG dev wiki, so you could have JTAGed the CPLD and fixed it that way instead.

I am glad no traces were cut on that mod... So it can be done still. ;)


BTW, the NEO-ZMC2 pinout is wrong on the wiki. The side that connects to NEO-Bx is fine, but the labels for the side that connect to the ROM bank data lines is completely wrong.

[ElBarto]

I am glad no traces were cut on that mod... So it can be done still. ;)


BTW, the NEO-ZMC1 pinout is wrong on the wiki. The side that connects to NEO-Bx is fine, but the labels for the side that connect to the ROM bank data lines is completely wrong.

Feel free to register and correct it :)

[l_oliveira]

Feel free to register and correct it :)

Furrtek did repair it yesterday, FYI : http://wiki.neogeodev.org/index.php?...mc2_pinout.png

Great stuff you guys have there btw ! You have no idea how it helps with repairs on real boards ! Great service for the community.

[veganx]

I know this might have something to do with l_oliveira thread "this is madness" but I want to make a clean thread with the entire story:

First, I would like to thank everybody involved in the NeoGeo Dev Wiki. because without their information this wouldn't be possible.
We used basically the information posted by Kyuusako and Furrtek. Thanks for your hard work on the Wiki.

The story:
I got scammed by an ebay seller from France that sold me the MVS converter saying that it was the Phanton-1.
Since my mother was visiting France she bought it on the shop and delivered it to me.
I had no chance to get my money back so I sent this to my friend l_oliveira so he could take a look at it: out project had began, to fix scaling and every other problem on the converter.


That's the result:





After a lot of talking with people on irc and gathering information from the wiki the idea came to replace the Neo-Flash fault emulated chip for a real ZMC2 from a dead MVS motherboard.


The result? Flawless!





This is metal slug X original cartridge working on a 9v 3-5 AES.
No graphic glitches.
This one works with my 5v, also.
The 9v is from l_oliveira and the 5v is mine.


About the sound problem:


The sound problems are not related to the converter, they are related to the multi cartridges.


The audio is divided in 4 parts: FM, PSG, ADPCM1 e ADPCM2. The audio problem is related to the ADPCM, because the ROM is in the cartridge.
The ZMC2 that is in the cartridge now won't touch any of the audio chipsets.
It must be some kind of fault in the FPGA on the 161 in 1 or a voltage problem.


The original cartridge worked fine.
Bootlegs worked fine: KOF2003, 2002, SVC Chaos.


And now that the NEO-CT0 code is out, we can build our own converters.
Soon a free alternative of a flawless converter will show up and people with PCB design skills will be able to build them.


This is awesome, thanks for everybody!

[derekb]

what is NEO-CT0

[veganx]

From the neo geo dev wiki: "PRO-CT0 is an early SDIP64 gate array chip used as:

• A sprite graphics multiplexer on AES carts and MVS boards."

So as you can see the reason for MVS cartridges not working with AES systems is the lack of this chip inside the cartridge. On the AES this chip is inside the cartridge and no the MVS this is inside the motherboard.

[l_oliveira]

what is NEO-CT0

NEO-CTO is the pixel serializer (latches, multiplexers and control logic) which converts the 32 bit sprites pixel data into a 8-bit serial stream for the format required by the NEO-Bx graphics chip.

On MVS the NEO-CTO (or NEO-ZMC2 on newer boards) is part of the system. On AES it's part of the cartridge. It was made that way to prevent the make of passive adapters... The adapter had a broken implementation of the NEO-CTO logic into a ACTEL "Flashlock" type CPLD. These are very expensive chips and people only use them when they want to make sure others won't be able to copy their design.

But LMAO, anyone can find a CTO or ZMC2 chip on a broken MVS or cheap AES cartridge. /facepalm.

[saturndual32]

This is awesome news!
Veggav and l_oliveira, you guys rock!

So, l_oliveira, are you going to sell this mvs to aes adapters?. If so, is there any timeline for release, and how much do you think it would cost.

[l_oliveira]

So, l_oliveira, are you going to sell this mvs to aes adapters?. If so, is there any timeline for release, and how much do you think it would cost.

No I won't but the neogeo dev folks will:

http://wiki.neogeodev.org/index.php?..._MVS_converter

Will be a affordable solution for replacing overpriced adapters.

[LeGIt]

I guess this is a bit like 'borrowing' a CIC from a Nintendo 64 donor cart to save on patching the ROM when loading through a flash cart, bit with a lot more work / wires?

I'm surprised it took people a couple of decades to think of this. With 20/20 hindsight it sounds like the kind of thing that was staring at people right in the face and could have been done long ago.

Then again, necessity is the mother of invention and when you're skint and have a couple parts lying around you're more likely to try a bit of bish bash bosh.

Anyhow, well done!

[veganx]

People did that but it was some kind of a secret so people can sell adapters for $400 like the Daedalous.

We just showed up the truth for everybody.

[saturndual32]

Is there any idea as to when these new adapters might be available?. Maybe in a couple months, half a year, maybe in a full year?. I have been saving money for the Phantom or the other one thats more expensive, but if this new one, is gonna have better compatiblity, i will definitely wait for it.

[Calpis]

Right now the prototype is being tested, it's hard to say when it'll be ready, maybe in a couple months, maybe much longer. For testing it must be sent to people with sizable MVS collections which takes some time.

[saturndual32]

Hey, that gives me time to get the money together, hehe. Besides, i am sure it will be worth the wait. Thanks for the info Calpis.