AES to MVS (plays AES games on MVS)

[Xian Xi]

I've managed to gather all the electronic parts needed (including the AES cartridge connectors).
Still looking for a working AES game to be the test game and a non-working MVS game to use the edge connectors.

Sorry dude, just been really busy lately. I'm stretched really thin right now.

 

[Apocalypse]

So thanks to Xian Xi and fluxcore I've been able to continue working on that project.

Here is the timing diagram of the OG system:



As I said before, C ROM data must be available before the PRO-CT0 on the MVS board latches them.
I first thought I could create a 48Mhz clock from the 24M signal in order to decode the 8 pixels before PRO-CT0 accesses C ROM data.
I'm not so sure it's the right solution now:



Even if the C ROM chips and the PRO-CT0 are fast enough to support the 48MHz clock, only 4 pixels (if not 2) would be correctly decoded.
Of course by modding the MVS board I think I could achieve a perfect result (by bypassing the PRO-CT0 chip on the MVS board and using the one in the AES cart and rerouting signals).
Another solution would be to decode the entire C ROM data after the game is booted and store them in a RAM which will mimic the OG C ROM chips in a MVS cart.
Does anyone with expert knowledge on MVS/AES have an idea?

 

[mastamuzz]

I remember Kenny had a picture of a neo hybrid on a front loader case, I have no idea if that thing worked or not but showed the MVS and AES cart inserted, anyone remembers that pic? he might know how to?

Just a thought I have no clue of what I'm saying ok.

 

[HeavyMachineGoob]

I'm pretty sure Kenny just mocked up that supposed dual system prototype, no way he has the skill required to pull off what's going on in this thread.

 

[Apocalypse]

I've built a second prototype but left C ROM data lines unconnected:



I first started the MVS board with dip SW1 = 1 to boot on the menu and see if the game is seen by the slot.
Success!



Ok, then I started the game. Everything works fine, sound is great, fix access is good also, in fact only sprites are missing:





That's all for today.

 

[greedostick]

Awesome project! You got a subscriber. Hoping for the best!

 

[Xian Xi]

Nice. Good job dude. Keep it up.

 

[Heinz]

This is exciting stuff to read/follow. Keep it up!

 

[zouzzz]

Very interesting project, awesome !

 

[HeavyMachineGoob]

It's an honor to witness the realization of the dreams of cheap 90s arcade operators everywhere. The JAMMA AES will soon be a thing of the past. Great project here!

 

[mikejmoffitt]

For this to work, you're going to have to patch in to the post-ZMC2/PRO-CTO signalling on the MVS board. De-serializing, only to have it be re-serialized by the MVS's ZMC/CTO is going to introduce a delay that you can't work around without having something buffering the data at a much higher speed than the data is being requested. If your route is to have the MVS be modded, then patching it in like you described earlier will be the way to go.

 

[Apocalypse]

For this to work, you're going to have to patch in to the post-ZMC2/PRO-CTO signalling on the MVS board. De-serializing, only to have it be re-serialized by the MVS's ZMC/CTO is going to introduce a delay that you can't work around without having something buffering the data at a much higher speed than the data is being requested. If your route is to have the MVS be modded, then patching it in like you described earlier will be the way to go.

Yes that's exactly what I've described before.
After analysing the signals here's what I found:
- C ROM address lines are maintained 625ns
- C ROM data latch happens 208ns after the rising edge on LOAD
Therefore, data must be unserialised from the AES cartridge between the moment when C ROM address lines are valid and the moment when C ROM data are latched by the MVS board.
Result is you have only 208ns to decode 8 pixels, 2 pixels per cycle, so 4 cycles needed.
Unfortunately that means dealing with a 192Mhz signal: unachievable...

Second option is to unserialised the whole C ROM before running the game. It means using a CPLD of some sort and a RAM buffer. Then MVS accesses C ROM data from the unserialised C RAM buffer.

Third option (discussed before), the easiest and fastest to experiment, is to reroute serialised signals directly to the MVS board then bypassing all the decoding process.

 

[HeavyMachineGoob]

It's times like this that make me believe we (home consumers) were meant to use AES, seeing how easy it is to make MVS converters. Only the C ROM serializer has to be reproduced in that case.

 

[wyndcrosser]

It's times like this that make me believe we (home consumers) were meant to use AES, seeing how easy it is to make MVS converters. Only the C ROM serializer has to be reproduced in that case.

Wait. What are you saying here? confused.

 

[aha2940]

Wait. What are you saying here? confused.

I think the summary is: better to have AES because MVS-to-AES converter exist since a long time, but AES-to-MVS do not fully exist yet.

 

[Razoola]

I think the position reached here is the reason why there has never been a AES-MVS converter made in the past.

As a project you have done great work, both your solutions will work you already know along with other members. Where you go from here is really down to you I guess. For me at least, the personal feeling of achievement is what would drive me to finish it if I were in your position. I guess you need to decide what you do after with it is the driver of which way you go because Im sure you can get it fully working either way.

If its personal achievement only it does not matter which way you choose. If its to try and make a product for sale or something you release plans for so people can build themselves then its quite important.

Would an AES-MVS standalone converter sell? I think it would but no where near in the numbers MVS-AES converters have. AES carts are more exspensive and is what drove the MVS-AES converters in the first place really.

Personally I think you should do it in a way where the MVS is modded to fit the device. Its the cheapest option as some games have a huge amount of c tiles (especially the ng-dev games) if you need to buffer the entire sprite graphics. I feel there are modders out there who would be interested in buying a product from you that they can fit into their CMVS to give an AES and MVS slot before they then sell it. NTM may be a good person you can get advice from as he does this kind of thing already with internal memory cards for example.

The other huge advantage which you may not have thought about is this. Making a converter only, your converting a single slot to still be a single slot. The other method done right, your converting a single slot into a 2 slot if you can mod it that way. This on its own may give interest in a purchase for some. a CMVS with MVS and AES slot that swaps games like a real 2SLOT... It sounds kind of sexy.

 

[GadgetUK]

I agree with Razoola and in particular his last point there about dual capability 2 slot - that does sound like the best outcome for something like this. I would think that decoding the pixel data in advance in some sort of cache could work, provided that the cache system can decode different size C ROMs. Not sure if that would cause any problems or not? The other trick you could do to test your theory in advance is perhaps interfere with the master clock - ie. pause the system at the point you need to decode the pixela, then release the master clock again once its decoded to the bus. That way it would run with slow down but if your theory is correct it would display correctly. Just not sure on implications of pausing the system and video sync.

 

[fluxcore]

Good progress, Apoc

 

[Apocalypse]

Thanks Raz for your advice.
I don't plan to sell anything. But it could be a good alternative for me to be able to play AES games as I don't own any AES consoles anymore.
MVS/AES combo in a 2 slot. Yes that sounds great!

Thanks everyone for your support!

[EDIT]
So as Raz suggested:

Personally I think you should do it in a way where the MVS is modded to fit the device. Its the cheapest option as some games have a huge amount of c tiles (especially the ng-dev games) if you need to buffer the entire sprite graphics. I feel there are modders out there who would be interested in buying a product from you that they can fit into their CMVS to give an AES and MVS slot before they then sell it. NTM may be a good person you can get advice from as he does this kind of thing already with internal memory cards for example.

So I did modify my 1 slot.
First I had to lift 10 pins on the NEO-ZMC2 chip (1/3/4/9/10/11/13/14/79/80).
I left pins 5/6/7 connected to the OG ZMC2 chip. Doesn't seem to be an issue.

Then I soldered wires on the pads and connected them as follow:

Signal - NEO-ZMC2 pin - AES pin
LOAD - 5 - A9 (CHA top)
EVEN - 6 - A7 (CHA top)
H - 7 - A8 (CHA top)
GAD0 - 79 - B32 (CHA bottom)
GAD1 - 80 - B33 (CHA bottom)
GAD2 - 1 - B34 (CHA bottom)
GAD3 - 3 - B35 (CHA bottom)
DOTA - 4 - B30 (CHA bottom)
GBD0 - 10 - B36 (CHA bottom)
GBD1 - 11 - B37 (CHA bottom)
GBD2 - 13 - B38 (CHA bottom)
GBD3 - 14 - B39 (CHA bottom)
DOTB - 9 - B31 (CHA bottom)

And...





It works flawlessly! Imagine if arcade operators had knew the trick. OK that's not easy but hey you could save thousands of $!

But I won't stop here. I would like to find a way to play both MVS and AES games on the same board and possibly having the possibility to mod a 2 slot to become both MVS and AES compatible.

 

[aha2940]

Thanks Raz for your advice.
I don't plan to sell anything. But it could be a good alternative for me to be able to play AES games as I don't own any AES consoles anymore.
MVS/AES combo in a 2 slot. Yes that sounds great!

Thanks everyone for your support!

[EDIT]
So as Raz suggested:


So I did modify my 1 slot.
First I had to lift 10 pins on the NEO-ZMC2 chip (1/3/4/9/10/11/13/14/79/80).
I left pins 5/6/7 connected to the OG ZMC2 chip. Doesn't seem to be an issue.

Then I soldered wires on the pads and connected them as follow:

Signal - NEO-ZMC2 pin - AES pin
LOAD - 5 - A9 (CHA top)
EVEN - 6 - A7 (CHA top)
H - 7 - A8 (CHA top)
GAD0 - 79 - B32 (CHA bottom)
GAD1 - 80 - B33 (CHA bottom)
GAD2 - 1 - B34 (CHA bottom)
GAD3 - 3 - B35 (CHA bottom)
DOTA - 4 - B30 (CHA bottom)
GBD0 - 10 - B36 (CHA bottom)
GBD1 - 11 - B37 (CHA bottom)
GBD2 - 13 - B38 (CHA bottom)
GBD3 - 14 - B39 (CHA bottom)
DOTB - 9 - B31 (CHA bottom)

And...

View attachment 34284

View attachment 34285

It works flawlessly! Imagine if arcade operators had knew the trick. OK that's not easy but hey you could save thousands of $!

But I won't stop here. I would like to find a way to play both MVS and AES games on the same board and possibly having the possibility to mod a 2 slot to become both MVS and AES compatible.

It's a very nice and great advance, congratulations man! however, I wonder if having World Heroes working really means that the adaptor will work perfectly. My reasoning is that WH is one of the older games, therefore is less complex, maybe trying one of the latest games, the ones having encryption (Garou, MS3/4/5, kof >99) would be nice.

Also, for converting a 2-slot into an AES/MVS would be nice to have the converter plugged into ones of the slots and bingo! you have a hybrid AES/MVS

Regards.

 

[Apocalypse]

It's a very nice and great advance, congratulations man! however, I wonder if having World Heroes working really means that the adaptor will work perfectly. My reasoning is that WH is one of the older games, therefore is less complex, maybe trying one of the latest games, the ones having encryption (Garou, MS3/4/5, kof >99) would be nice.

I know but that's the only AES game I own and it was given to me by Xian Xi lately.

Also, for converting a 2-slot into an AES/MVS would be nice to have the converter plugged into ones of the slots and bingo! you have a hybrid AES/MVS
Regards.

I'm working on it but that won't be easy.

 

[Razoola]

Nice one Apocalypse. I am not sure what help I can give you on what required on making both slots usable at the same time, I guess looking at a genuine 2SLOT will help but just be aware there are 2 different types. One operates more like a single slot and the other like the 4 and 6slots. This is in relation on the required state of the system for a carts P ROM to latch onto the 68k bus. One requires the M and S ROM from the cart to be active and the other is connected as soon as the cart swap flag is written.

What is on your side however as there is no hard coded bit or flag on a 2 SLOT to tell the bios it is a 2SLOT or 1SLOT. The bios basically swaps slots and compares the P ROM header to see if it finds 2 different games because there is nothing else it can use to tell the difference. So all you need to do is implement the swapping logic and the bios should take care of the rest for you.

You are right on your arcade operator point, if what you have done here was known in the ninties or the universe bios was available back then the Company would have has some problems with its pricing.

 

[Xian Xi]

I know but that's the only AES game I own and it was given to me by Xian Xi lately.

Hopefully we can get someone to donate some newer games or at least one that uses different lines.

 

[Apocalypse]

I don't think the difference between the 2 slots would be an issue.
Anyway I've been another step further.
I've tried to make my 1 slot compatible with both MVS and AES. Here's the solution I've tested working:



In fact it reroutes signals depending of the adapter being plugged or not.
But it's still to complicated (lifting 10 pins, soldering 25 wires in the MVS). I've got few other ideas I'd like to experiment and with some tricks it could do it.

 

[fluxcore]

Unfortunately the only games I can help test with are samsho1, aof, ffs, cyber lip. And I don't know anyone else local with AES carts, either... :/