What's new
Peak to peak would say it is AC ;)
dc_ac_current.jpg
 
I’m not an expert on this, but what I do know is that a ‘normal’ video signal (RGB, VGA etc.) is around 0.7v peak to peak, where Jamma is around 3.0v peak to peak.

That’s why superguns have resistors to bring the voltage down to connect to your TV.
What you are trying to do is the opposite, so either you monitor must support the ‘weak’ signal, or you should boost your signal.
 
I’m not an expert on this, but what I do know is that a ‘normal’ video signal (RGB, VGA etc.) is around 0.7v peak to peak, where Jamma is around 3.0v peak to peak.
That makes two of us!
That’s why superguns have resistors to bring the voltage down to connect to your TV.
What you are trying to do is the opposite, so either you monitor must support the ‘weak’ signal, or you should boost your signal.
So far so good with what I am attempting. In my situation, no need for clamping, DC restoration, or video amping for the consoles I am targeting (PS1, PS2, Saturn, Dreamcast). The only thing that is needed is harvesting the RGB signal from the consoles with the proper cables or adapters, and stripping sync where needed. And having a monitor that can accept the AC coupled RGB signal from consoles. In my situation, that is a Wells Garner K7000. Right now I am getting a nice image with all the those consoles on that monitor. I am even impressed with the small sample of PS2 games that play @480i!

Here are a couple of snaps from the Dreamcast where I am playing around with 240p Test Suite and Sturmwind.

240p.JPG

Sturmwind01.JPG
 

Attachments

  • 240pTestSuite.JPG
    240pTestSuite.JPG
    226.1 KB · Views: 115
  • Sturmwind02.JPG
    Sturmwind02.JPG
    199.9 KB · Views: 149
I’m not an expert on this, but what I do know is that a ‘normal’ video signal (RGB, VGA etc.) is around 0.7v peak to peak, where Jamma is around 3.0v peak to peak.
Also referred to as TTL transistor-transistor logic level voltage.
 
Looks like you already got the answers you were looking for :)

That's pretty sick, I might look into getting a Wells Gardner for my next cab so I can play consoles on it without wrapping my head around all this stuff. Also, 1V to 5V means you can use your consoles without a video amp, they'll just look slightly darker but you can compensate with your monitor's brightness control.

Very interesting, I'm wondering which other monitors are capable of such a wide range.
 
Looking forward to see what comes out of this too.

@acblunden2 I too am targeting PS1/2, Saturn, Dreamcast and would love a very simple all in one solution that I dont have to have too much technical knowledge to set up.
 
Very interesting, I'm wondering which other monitors are capable of such a wide range.
Works on my NeoTec NT-33c too. That is a big-ass 33" monitor however.
Looking forward to see what comes out of this too.

@acblunden2 I too am targeting PS1/2, Saturn, Dreamcast and would love a very simple all in one solution that I dont have to have too much technical knowledge to set up.
I think you are mostly there since you picked up the MC Cthulhu boards for control interfacting. Honestly, without that, it would be a much harder proposition. I missed the boat on the MC Cthulhu's again for some reason. Hopefully, they will have another batch soon. Let me know how those work when you get them. I am considering them too even though I already have the PS360+'s.
 
I think you are mostly there since you picked up the MC Cthulhu boards for control interfacting. Honestly, without that, it would be a much harder proposition. I missed the boat on the MC Cthulhu's again for some reason. Hopefully, they will have another batch soon. Let me know how those work when you get them. I am considering them too even though I already have the PS360+'s.
Damn, didnt realise they sold out so quickly. I only bought 2 kits and they were for a multi madcatz sticks, was thinking of buying 4 in total. I guess if I want to do this I'd also need to wait until they are in stock again.

I am waiting on a ton of other stuff to be able to mod them into my sticks but I will update and let you know how these go.
 
I reached out to Paradise and they said they are getting some more MC Cthulhu's in 1-2 weeks.
 
Paradise has them back in stock. I swooped up 2. Should be up and running playing consoles on JAMMA shortly.
 
Got the two MC Cthulhu boards, but one is dead, sonuva!! Anyways, here are some more pics. Of PS1 and PS2 in action. I am Free MCbooting the PS2 games. Will mod the PS1 and eventually get a PSIO. Hoping to grab a Phoebe for the Saturn. Already have a GDEMU for the Dreamcast.

Not trying to collect. Just want to play the games on a cab. The whole purpose of this effort is to play titles that originated in arcades but ended life on consoles (Gradius V, R-Type Delta, Final). Or play titles that were inspired by arcades but only lived on consoles (Einhander). Or are just too damn expensive to own the arcade version of, so I'll settle for a good console port over MAME emulation (too many to list).

Silpheed.JPG
GradiusV1.JPG


And here are a few that are best played on the comforts of a couch or have analog control and can't be played on a cab. I was just seeing how these looked on my cab:

PS1.JPG
ZOE1.JPG
 

Attachments

  • GradiusV2.JPG
    GradiusV2.JPG
    63.6 KB · Views: 105
  • RTypeFinal1.JPG
    RTypeFinal1.JPG
    91 KB · Views: 125
  • FF7.JPG
    FF7.JPG
    90.6 KB · Views: 131
  • MGS3.JPG
    MGS3.JPG
    99.6 KB · Views: 128
Sweet.
WTF about the board though. Are they not tested before they are sent? Is there a way to test these without installing them in a stick as I haven't got all the required parts to begin installing them in sticks.
 
The manual says to hook them up to a PC via USB and check in the control panel under USB Gamepads if it shows up. That's what I did and got nothing. You can test the buttons by just screwing a wire into anyone one of the grounds, then touching the other end to any part of the screw posts and watch them register on the PC.
 
Oh did the other one show up? I thought that it needed a button combo to be pressed to show up in windows or something?

Edit: Just tested both mine they show up as per the manual under controllers as MC Cthulhu edition. Seems the start select button combo is for firmware updates.
 
Last edited:
After lots thought on this subject, I think I have figured out to make Console-to-JAMMA work on any JAMMA cab (not just my K7000):
  • Video must be harvested from SCART, amped, clamped, and DC restored
  • Sync must be harvested from SCART, stripped, and amped as needed
  • Audio must be down-mixed from stereo to mono, then amped for JAMMA while still allowing for the option of amped stereo output
  • Controllers are interfaced via the MC Cthulhu
Everything is then plugged into a PB.JAMMA fingerboard for hook-up into a JAMMA cab. Out of the above, the easiest to figure out is the controllers thanks to the MC Cthulhu. The hardest to figure out was the audio, then video, then sync. I feel what I have drawn up in my minds eye will work. I bought some parts and they'll arrive from overseas of the course of the next month. The most expensive part is the MC Cthulhu. I will set this up so that I don't pigeon-hole those PCB's to being soldered into a JAMMA cab-only solution. Want to be able to use them with fight sticks too. Saves having to buy another set MC Cthulhu's. Given that, this should be an inexpensive project (~$25 for all the parts excluding the MC Cthulhu's and the sweat equity) that will hold me over until viletim releases his next version of SCART2JAMMA.

This will probably will be the last post I make in this thread on the subject since now it has ventured far from what I originally asked for.
 
Please do keep posting and show your setup when done. I was going to do something basic such as a DC to Jamma but would much rather get an all in one solution which sounds like the viletim solution which I eagerly await.
 
Back
Top