JAMMA cabinets & power supplies

[ZippySLC]

I read somewhere that the JAMMA spec power supply requires the load of the game board to be present to power on the monitor. I've tested that out and found that my cabinet doesn't power up if the board isn't present (only the marquee lights up)

My goal is to be able to power at least the marquee, coin door, and monitor using the switch on top of my cabinet. But that's going to be hard without the JAMMA board being present.

Is there a JAMMA compatable power supply that doesn't require the board, or is there a way of putting a dummy load on the PS to have it power up everything? I was planning on getting one of those "smart" power strips that sense when a device is turned on and power everything else and using that to power the PC, speakers, etc. when the cabinet is powered up.

I get the feeling that most people with JAMMA cabinets keep them with the JAMMA spec -- anyone have a site that details a JAMMA to MAME conversion?

[rampy]

What I did was remove the the AC input tabs to the switching power supply., which makes sure that it doesn't run without a load, cuz that part wont be able to turn on.  (note: you'll lose the coin door lights power but marquee/monitor should still fire up... also note: you CAN also use a load resistor so the switching powersupply won't blow)

As long as the REST of the wiring is intact and you can trace the in coming AC mains through the fuses, filter, and up to the switch and back down to the isolation transformer which should then run up to the monitor (depending on the monitor,.. you might not need/have a iso transformer if it's a modern monitor)

http://www.dameon.net/BBBB/basic-ac.gif
real bob roberts wiring overview  I found those were good starting points for basic wiring...

the PC2jamma page is also helpful (google for it)

I'd also suggest looking in to ultimarc.com's J-pac product.

rampy

ONE other thought... one thing that bit me when converting a jamma cabinet is the failsafe/test switch.  When the back door was off or open a safety switch was "open" position and cut the power.  (Shrug* ... good luck.

[ZippySLC]

These pics should give a general idea of what I have going on inside this cabinet:





I believe that big chunky thing next to the power supply is the transformer for the monitor. It's dated 1989, so I am assuming that it doesn't count as a modern monitor.

I was considering using the JPAC but I find the JAMMA interface to be limiting for what I want to do. I just want one switch to turn everything on!

My cab doesn't have any safety switches. I can pull the back panel off, and have the PCB shelf out of the cabinet and it would still power up. It's a fairly generic cabinet.

[SirPeale]

I believe that transformer is what's called an isolation transformer.  If that's the case, you DO NOT want to be without it.  Bad, bad, bad bad bad things will happen without it.

[rampy]

Taking another crack at this with embedded text:

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>>I read somewhere that the JAMMA spec power supply requires >>the load of the game board to be present to power on the >>monitor. I've tested that out and found that my cabinet doesn't >>power up if the board isn't present (only the marquee lights up)This is true in that running a power supply without a load can blow the powersupply.  I wonder if you have a smart power supply that knows to not turn on... but regardless  if you look at those wiring diagrams I posted alink to if the marquee is lighting, there's most likely power running to the monitor...

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>>My goal is to be able to power [b]at least[/b] the marquee, coin >>door, and monitor using the switch on top of my cabinet. But >>that's going to be hard without the JAMMA board being present.
It doesn't have to be... especially if you are using a smart power strip below...

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>> I was planning on getting one of those "smart" power strips >>that sense when a device is turned on and power everything >>else and using that to power the PC, speakers, etc. when the >>cabinet is powered up.This shouldn't be a problem once you get to the point of using the smart power strip.  You'd just leave the cabinet power switch ON and plug it into the strip and when you turn on your pc the marquee, monitor, etc will turn on.


>>>anyone have a site that details a JAMMA to MAME conversion?
pc2jamma page link (the whole site has lots of info -- although if you go jpac you'll have a much easier go of it)

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>>I believe that big chunky thing next to the power supply is the >>transformer for the monitor. It's dated 1989, so I am assuming >>that it doesn't count as a modern monitor.You are correct sir... and Peale is absolutely correct that it's required and important for safety reasons and bad things can happen without it in place.

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>>I was considering using the JPAC but I find the JAMMA interface >>to be limiting for what I want to do. I just want one switch to >>turn everything on!These really are two separate criteria.  The one switch is really not a problem with the powerstrip you discussed earlier.

What do you find limiting about the jamma interface?  What is the control panel setup that you desire?  If it's 4 player, yeah.. I imagine a jpac isn't going to cut it alone for you.  But if you are referring to wanting 6 or 7 buttons per player the J-pac can accomodate you.  See the JAMMA standard is for 2 players each with 3 buttons (max) and 1 credit and 1 player start button each. BUT there's the concept of JAMMA+ where an extra harness (often called a "kick" harness because it consists of the "kick" buttons in say Street Fighter II) runs the additional wires to the additional player buttons.  The J-pac has extra headers/terminals to accomodate that.  The j-pac is a very handy and easy way to interface a PC to a JAMMA wired cabinet with a minimum of muss and fuss.

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>>My cab doesn't have any safety switches. I can pull the back >>panel off, and have the PCB shelf out of the cabinet and it would >>still power up. It's a fairly generic cabinet. My bad, it was just a shot in the dark and was sharing a small gotcha I had with a cabinet I've been working on.  I'm *guessing* that your switching powersupply knows not to let itself turn on without a load.  You could check with a voltmeter (or look at the coin door lights if they are intact/working)... THe switching power supply should have no bearing on the monitor though.  Take a look carefully at the monitor to see if it's "on" but just doesn't have a screen as their is no source input...  (but be careful back there for gods sake!)  There's bound to be a tube back there with a slight orange glow (or you can see the screen sorta flicker on the front when you apply power on/off)

I'd look at those links I posted earlier and compare them to your cabinet.. .from the pictures you posted the diagram is very relavent.  I'd look into the j-pac as a plug and minimum wiring and play option.  You can definitely get there from here, but you need to make some decisions and understand the ramifications of those decisions.

I'll try to help as best as I can with links and my small body of experience... =P

good luck --> and please clarify as to what your project goals are i.e. which controls...

Rampy

[ZippySLC]

Taking another crack at this with embedded text:

This is true in that running a power supply without a load can blow the powersupply.  I wonder if you have a smart power supply that knows to not turn on... but regardless  if you look at those wiring diagrams I posted alink to if the marquee is lighting, there's most likely power running to the monitor...

I honestly have to spend more time looking over the wiring diagrams. I'm 99% sure that the monitor didn't fire up, nor did the coin door lights, but the marquee bulbs did.

This shouldn't be a problem once you get to the point of using the smart power strip.  You'd just leave the cabinet power switch ON and plug it into the strip and when you turn on your pc the marquee, monitor, etc will turn on.

The goal was, however, to not have to actually physically power up the PC by pressing a button. I wanted the PC to come on when it got AC power via the power strip. I know some BIOS'es will let you do that.

You are correct sir... and Peale is absolutely correct that it's required and important for safety reasons and bad things can happen without it in place.

Then I will leave it in place.

What do you find limiting about the jamma interface?  What is the control panel setup that you desire?  If it's 4 player, yeah.. I imagine a jpac isn't going to cut it alone for you.  But if you are referring to wanting 6 or 7 buttons per player the J-pac can accomodate you.  See the JAMMA standard is for 2 players each with 3 buttons (max) and 1 credit and 1 player start button each. BUT there's the concept of JAMMA+ where an extra harness (often called a "kick" harness because it consists of the "kick" buttons in say Street Fighter II) runs the additional wires to the additional player buttons.  The J-pac has extra headers/terminals to accomodate that.  The j-pac is a very handy and easy way to interface a PC to a JAMMA wired cabinet with a minimum of muss and fuss.

Hmm. I ordered the I-Pac. I was planning on two players, six buttons per player, plus some extra buttons to control various aspects of MAME. I wanted to also keep the coin door operational to trigger the credits to register.

My bad, it was just a shot in the dark and was sharing a small gotcha I had with a cabinet I've been working on.  I'm *guessing* that your switching powersupply knows not to let itself turn on without a load.  You could check with a voltmeter (or look at the coin door lights if they are intact/working)... THe switching power supply should have no bearing on the monitor though.  Take a look carefully at the monitor to see if it's "on" but just doesn't have a screen as their is no source input...  (but be careful back there for gods sake!)  There's bound to be a tube back there with a slight orange glow (or you can see the screen sorta flicker on the front when you apply power on/off)

The coin door lights were definately off. My monitor gives a slight flicker when it powers up, which it did not do when I disconnected the board.

I'd look at those links I posted earlier and compare them to your cabinet.. .from the pictures you posted the diagram is very relavent.  I'd look into the j-pac as a plug and minimum wiring and play option.  You can definitely get there from here, but you need to make some decisions and understand the ramifications of those decisions.

Well, the idea was to pretty much ditch all of the JAMMA spec wiring except for power to the monitor, marquee, and coin doors. I wanted to keep the control wiring as "open-ended" as I could for future expandability. What I would love to do is just get it so I can power on the monitor, marquee, and coin door lights. I understand that I can run the coin door lights from the PC, but I would rather not.

I'll try to help as best as I can with links and my small body of experience... =P

good luck --> and please clarify as to what your project goals are i.e. which controls...

I definately do appreciate your help! I haven't finalized exactly what I want, but these are the basics:

- Two HAPP 8 way joysticks (with the bases that can switch them to 4 way)
- Player 1 and Player 2 start buttons
- 6 buttons per player
- Various buttons to control MAME (pause, reset, menu, etc.)
- HAPP Trackball (I bought a USB one, so it doesn't really matter)

I have an ArcadeVGA card on order, ordered with the VGA breakout cable. (So I will also need wiring specs for the video input of my monitor)

[ZippySLC]

I stand corrected - the monitor does power up without the JAMMA board. The only thing missing is the coin door light.

So I guess that I could ditch the switching power supply and get a small 12v PS for the coin door lights, or run them off a drive power connector on the PC's power supply.

[rampy]

You could do that... and that's what I'd recommend if you are NOT going to use an jpac...  basically ignoring/removing the switching powersupply completey  (I'd disable the AC lines into the switching power supply  as I alluded to initially if that's the route you are going)

Good luck with your project... keep us posted.

Rampy