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Console SCART to Arcade/JAMMA - How does one get a Simple PCB to be Fabricated?

RealMFnG

RealMFnG

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There are a few console games that I would love to play on an arcade cab (Sturmwind and Einhander). Ideally, would want a fingerboard that would plug right into the JAMMA edge connector to facilitate this and keep it clean. Assuming the following:
  1. Video output from consoles will be in the form of SCART via individual cables for each consoles
  2. Audio will be handled through the cab's external stereo audio amp
  3. Control interface will be handled externally via pad hacks
Effectively, the JAMMA fingerboard would simply have:
  1. Female SCART connector outputting RGB/Gnd/Sync via JAMMA fingerboard
    1. w/Sync stripped from the SCART composite sync via LM1881 circuit
  2. Screw terminals to connect from pad hack to JAMMA edge through to fingerboard
    1. w/extra screw terminals that maps to CPS2 style female kick harness connector
Seems like a simple PCB to build and I understand this can be rigged up. But I want to keep this clean. Also, there have been other spirited versions of this but availability of those solutions is a problem (like this and this). Anyone with such skills want to take this on? Or direct me to how to accomplish this?
 
Finding one of Tim’s board would be the easiest solution...

Other than the main pcb, all the add-ons are still available, so that would help I think.
 
I emailed Tim. Will wait for his response. Tim's solution would require a pad hack and doesn't take into account the need for more than the standard 3 Jamma buttons. Lemony's solution is more complete since it doesn't require pad hacking. Let me see if I can reach out to Lemony on Facebook. Report back once I get an update.

Still though, fabbing up such a simple board should be easy if you know where to go, yeah?

Also, @PascalP, where are all these cab icons in your signature coming from?
 
Yeap. Heard of the Jammacon a while back. Availability is always a problem with these things. Plus AFAIK, there is no Dreamcast Support. Seems the solutions always have some quirk whether it is availability or console support. Let me email Shane Kiely about the Jammacon anyway.
 
Seems there are limitations with every solution or a trade off with greater cost. Blah. Think I will build something on my own. Sooooooo, given:
  • I have to buy SCART cables for each console anyway, I may as well buy the console SCART cables with the Sync stripper built in
    • Not much difference in price
  • I already have two Akishops PS360+ that have been sitting around for like 4 or 5 years that I have not touched
    • Saves me from pad hacking, and
    • I have the connectors for the two consoles I want to wire up already: PSX and Dreamcast
    • Plus can buy additional cables for other consoles if desired
So with that said, I'll do this instead:
Biggest expense here will be the SCART cables which as stated earlier, I have to buy anyway even if I have to go with already produced choices listed already. So the only things I will have to buy are the female SCART connector, the Jamma fingerboard, JST NH male connectors for the fingerboard, and maybe a project box for the PS360+'s. Fingers crossed.
 
What kind of monitor are you hooking to? Do you need to consider amplifying the video levels?
 
It's not that easy.

Consoles output an AC coupled video signal while arcade monitors expect a DC coupled one.

In layman terms, this means that the brightness will change depending on what's shown on screen due to a missing voltage reference.

A video amp is not enough, you'll have to build a clamp or a DC restoration circuit to achieve a good and stable picture on your monitor.

I've been scratching my head for at least a year and had a semi-working project but had to give up due to time/money issues.

I still have most of the components needed, but will is lacking, have other stuff to do, blah blah blah.

Maybe one day I'll get back to it.
 
skate323k137 said:
What kind of monitor are you hooking to? Do you need to consider amplifying the video levels?
Click to expand...
It would be a Wells Gardner K7000. Depending on the console, video amplification is a consideration. Not the case with the Dreamcast or the Saturn however.

donluca said:
It's not that easy.

Consoles output an AC coupled video signal while arcade monitors expect a DC coupled one.

In layman terms, this means that the brightness will change depending on what's shown on screen due to a missing voltage reference.

A video amp is not enough, you'll have to build a clamp or a DC restoration circuit to achieve a good and stable picture on your monitor.

I've been scratching my head for at least a year and had a semi-working project but had to give up due to time/money issues.

I still have most of the components needed, but will is lacking, have other stuff to do, blah blah blah.

Maybe one day I'll get back to it.
Click to expand...
Yeah, think I have to make concessions depending on what console it is if I go the DIY route. Dreamcast and Saturn should be no problem. It is the other consoles however that are the concern. However, I do have a J-Pac Video Amp laying around that I've never used. If I were to just take a SCART female connector and harvest RGB/Sync/Ground, then connect that to a HD15 Breakout Terminal to connect to the J-PAC Video Amp, that would take care of the video amplification needs. I also can just use the J-Pac for the video amplification, but then would run into the problem of having to wire the Jamma buttons separate from the Jamma connector.

But since stated in my OP that I want to keep it clean, a Frankenstein solution isn't what I am aiming for. Given that, I am strongly considering Shane Kiely's Jammacon in this configuration:
  • €120 for JammaCon board + 2 Player adapter
    • The 2 Player adapter I would then select would be the €20 Padhack board
    • Also, would get his €10 CPS1/CPS2 kickharness adapter
The problem with that is his solution says nothing of video amplification. I do see a what looks like a contrast pot on his board. But he states as a disclaimer:

"Whilst every effort has been made to ensure this works with as many cabinet configurations as possible. Its simply impossible to guarantee it will work 100% with every cabinet type out there given the range of monitors, power supplies, harnesses etc. If it doesn't work for you, just return it for a full refund."

I did invite Shane to this forum to share his project however. As for Tim's solution, he does have video amplification. But he hasn't replied yet. Shane's Jammacon will be available again in January. No word on Tim's. See what I mean about concessions?
 
Going back to the OP however, if I could amend the original requirements, it would be really nice if someone would make a Jamma finger board that allows interfacing to a console:
  • Assume control interfacing would be handled externally, would simply need connectors to send external signal to Jamma connector. Scew terminals would be best where possible
    • Would also need terminal connection for CSP1 or CPS2 style kick harness
    • The standard 2x10 pin header for console PCB's are good too
    • If screw terminals can't be used, thru-holes for JST NH type connections would work
  • Add in a SCART female connector where,
    • RGB/Sync/Video Ground are passed to Jamma connector
      • Jumper can be added in to re-route video to a pot to add in video amplification for consoles that need it
      • Power needed for video amplification can be pulled from Jamma edge or external power source (see PB.Jamma note for more details)
      • CSync stripper circuit is built in or pinout built into pcb allowing for the user to add in the LM1881 circuit.
    • Video Amplification is built in
      • Pulling in power from Jamma edge connector
      • Or from external power source (see details from PB.Jamma fingerboard
  • Stereo Audio is extracted from SCART and outputted to 3.5mm jack connector
    • Jumper can be added to re-route audio to Jamma connector
Basically, what I am describing is a simpler/less costly version of what Shane's Jammacon board with the Padhack board built in, eschewing the need for interchangeable daughter boards since for achieving console control interfacing can be achieved via Toodles MC Cthulhu or a PS360+ or pad hacks.

COGS for this would be I'd imagine, $15 at most? Selling point should be $60 and would facilitate mass consumption. Expanding the PB.Jamma board would be great. Users can add in just about everything else. Also love how the PB.Jamma board allows for power to be pulled externally in addition to the Jamma edge. A bare such Jamma Fingerboard/PCB would retail for $15 at most. @Lemony Vengeance, is this something you can do?
 
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I wonder why Shane didn't do a Dreamcast solution originally with his first set? Because of Naomi and Net booting? Or because of those other Dreamcast to Jamma kits that are now impossible to find?

Anyway, I wish you luck with this...if it easy enough to implement I may follow your lead down the road.
 
SEGASHIRO said:
I wonder why Shane didn't do a Dreamcast solution originally with his first set? Because of Naomi and Net booting? Or because of those other Dreamcast to Jamma kits that are now impossible to find?

Anyway, I wish you luck with this...if it easy enough to implement I may follow your lead down the road.
Click to expand...
He said something about analogue controls:

"Later console generations that largely depend on analogue controls are a poor fit when it comes to mapping them to a single 8 way digital joystick. Exception to this would be the Playstation(s) owing to the decent amount of games available that don't require the analogue controls."
 
Man, I'm reading Tim's SCART2Arc solution and it is almost perfect. And the price point with the current exchange rate is quite nice ($70 AUD last I checked) Thing he is missing or that I would ask to have improved on is:
  • The ability to harvest buttons 4,5, and 6 outputting to a pin header for either a CPS1/CPS2 connection
  • The fingerboard is a little too shallow for some of the cabs that have a differ edge connector
  • Skip the daughter board idea and go with 2x10 pin header connection that is so prevalent with the latest console PCB's like the PS360+, Brook, and Tootles MC Cthulhu PCB's
    • Consolidating everything into a single PCB
  • Ability to turn off/on Sync stripping with a rocker switch
  • Ability to turn off/on video amplifiction with a rocker switch
  • Reposition screw terminal connection away from Jamma connection
What it has that is rather brilliantly does:
  • Can draw power for CSync and Video Amp via Jamma edge or externally via terminal screw connectors
    • Jamma edge power allows to keep everything Jamma standard
    • External power sourcing not through Jamma edge allows for shutting down the Jamma power saving power by not needing to turn on arcade power supply
  • Can input RGB/Csync/Video Ground through terminal screw connection and not just SCART connection
    • This would allow for interfacing a MAME PC with a DB15 breakout terminal through the same board and with the same external controller PCB's that support PC's (mentioned above)
    • Also allows interfacing video for consoles that have native 15khz output like the Dreamcast, removing the need for a SCART cable (additional expense)
  • Extract's stereo audio and can send it externally
  • Can extra mono audio and send it to edge connector or externally
Sigh, always a trade off....... I hope Tim responds soon too.
 
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Someone pinged me about this thread so here’s my two pennies.

I’m going to be designing a PCB that combines everything I put in my adapters (video\audio amps, sync cleaner, etc..) and turns it into an easy to use do-it-yourself project platform. i just need the time to sit down and work on it.

As far as video amps go, I’ve been using one that works with pretty much whatever console I’ve thrown at it. Pretty versatile little thing :).
 
Ahhhhh yeah! Yeap, that was me that pinged you on Facebook. That's awesome news bud! If it is anything like the PB.Jamma board, sign me up! Great thing would be it would be available in the US.
 
I'll throw another penny in the pot seeing as my board is part of this discussion (Jammacon).

  1. Video amplification/correction is not an option - its a requirement. The video output signals from consoles have different specs to whats required by an arcade monitor. What might work on our monitor is not guaranteed to work on all monitors - hence my disclaimer, although I not heard on any cab its has not worked in yet.
  2. I dislike pad hacks. The whole point of my project is to be a simple plug 'n play solution that extendable with different consoles. Not everyone has the skill sets or interest in hacking together their own solution - the number of pad hack adapter I've sold compared to dedicated console adapters would seem to back this up.
  3. I would like to offer Dreamcast & Gamecube & XBOX etc adapters, but with each newer generation of console the complexity of the controllers has increased and the number of games suitable for a cab has greatly decreased. A controller for a Saturn can be designed quickly with some basic logic whereas Playstation has relatively complex firmware that requires a lot of testing. Dreamcast is even more complex, but its the challenge I like so may happen when I get the time :)
  4. I do this a hobby, everything is handmade when I get the spare time maybe this explains the availability problems. So not interested in large volumes and lets be honest if where was a large volume demand you can be sure Aliexpress would be full of them.
  5. Your pricing is way off :) I would love to be able to make them for $15, but I only use branded parts from Farnell & Mouser so no fake or crappy components. Of course I make money on them, otherwise I'd be an idiot given the time put in and this funds my hobby so profits usually get spent on more retro stuff :)
  6. If you can solder and read a datasheet then its not terribly difficult to build one of these so definitely give it a go but never underestimate the shittyness of a Jamma power supply :)
 
Yeah, pricing on this is WAAAAAAAAAAAAAAAAAAAY off. Branded parts cost $$, and the cost to have them mass produced is enormous, especially since you need mass quantities to hit the MOQ. Hand preparation takes time, but honestly I would rather have everything on a single board than hand wire all the components like I’m doing now :). I love you guys, but seriously, the headaches and time I spend at my work bench is just going up. the margin of error goes down the less complex something is, so putting everything on a board just makes sense.

I’d go over specs, but it’s too early to do so.

I’m in Iceland on holiday right now, and will be in Mexico for New Years. The plans will be drawn up shortly after that. I’ll do my best to fund this on my own, primarily because I hate the idea of kickstarters. It’s too much pressure to get a product out.
 
TheLastBandit said:
I'll throw another penny in the pot seeing as my board is part of this discussion (Jammacon).


Video amplification/correction is not an option - its a requirement. The video output signals from consoles have different specs to whats required by an arcade monitor. What might work on our monitor is not guaranteed to work on all monitors - hence my disclaimer, although I not heard on any cab its has not worked in yet.
Click to expand...
Hi Shane, thanks for accepting the invite and welcome to probably the most positive forum for arcade projects anywhere.

Not with every console would video amplification be needed. And in those cases where it is not needed, separate terminal connections for outputting RGB/CSynch/Video Ground to the Jamma connection would allow for flexibility to connect those exceptions for output to the Jamma connection. For example, a GroovyMAME PC running CRT Emu Drivers or a Dreamcast.

Tim's SCART2Arc has this option. As of right now, if someone were to use Tim's SCART2Arc, they could run all of their consoles and a GroovyMAME PC all in one cab with his board and one of the multi-console PCB's. There are some design choices that I am suggesting some improvements can be made.
TheLastBandit said:
I dislike pad hacks. The whole point of my project is to be a simple plug 'n play solution that extendable with different consoles. Not everyone has the skill sets or interest in hacking together their own solution - the number of pad hack adapter I've sold compared to dedicated console adapters would seem to back this up.

I would like to offer Dreamcast & Gamecube & XBOX etc adapters, but with each newer generation of console the complexity of the controllers has increased and the number of games suitable for a cab has greatly decreased. A controller for a Saturn can be designed quickly with some basic logic whereas Playstation has relatively complex firmware that requires a lot of testing. Dreamcast is even more complex, but its the challenge I like so may happen when I get the time
Click to expand...
Everyone hates pad hacks. Pad hacks sometimes are necessary. Especially early in a consoles life. But these days going with the Brook board, Toodles board, or the PS360+ multi-console PCB's is a much better option. As is, these boards would interface right to your Padhack board and would have multi-console compatibility.
TheLastBandit said:
I do this a hobby, everything is handmade when I get the spare time maybe this explains the availability problems. So not interested in large volumes and lets be honest if where was a large volume demand you can be sure Aliexpress would be full of them.
Click to expand...
Anything to do with the arcade hobby is a small niche market. Everyone wants to reward devs. Check this thread.
TheLastBandit said:
Your pricing is way off I would love to be able to make them for $15, but I only use branded parts from Farnell & Mouser so no fake or crappy components. Of course I make money on them, otherwise I'd be an idiot given the time put in and this funds my hobby so profits usually get spent on more retro stuff
Click to expand...
$15 would just be for the bare fingerboard. The user would then add in the parts that are needed at their own expense (LM1881 circuit, video amp, SCART female terminal, audio amp. Check Lemony's post above.
TheLastBandit said:
If you can solder and read a datasheet then its not terribly difficult to build one of these so definitely give it a go but never underestimate the shittyness of a Jamma power supply
Click to expand...
Soldering, yes. Data sheets not so much :). Tim's SCART2Arc and Lemony's JB.Jamma fingerboard allow for external powering as an option instead of just power from the Jamma edge or just as you say, the shitty arcade PSU.

Anyways, welcome to the forum. Please stay a while and if you don't mind, post an intro here so that others know you have arrived and can support you.
 
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Yeah @Lemony Vengeance, the $15 price would just be for the bare fingerboard. The assembly, leave to the user which would cut costs. I still could be way off. But given the PB.Jamma is only $5? Adding in thru hole connections for an expanded version of that PCB for the other circuits (syn stripper, video amp, SCART, audio) couldn't be that much more?
 
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