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Home Arcade System

That looks good!

Use your multimeter to check for +5V at the JAMMA edge of your board and adjust power supply accordingly. Should read +5V at pins 3 and 4. The voltmeter on the HAS should be a good way to get a rough reading of voltage at the JAMMA edge of your board. Taking a measurement with a multi meter from the board is the most accurate way to read voltage.

PS: Every board is different on voltage and current draw so, depending on the board, you may have to adjust your power supply each time you swap a board. You should aim for 4.95V - 5.05V.
 
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rcboosted said:
Thanks everyone who chimed in. I switched to TTL and it worked as expected using the mini din 8 and HD15 adapter on AV3 RGBS. The only reason I'm using Din8 and VGA is because my scart cable is still being made by retro-access with no ETA. This cable and adapter were for future PCB/situation that might need it.

Got a couple of questions for RGB

@RGB
1. How do I set the video dial correctly? Currently it's set to 500ohms measured from outside pin to center pin while unit is off, this is the resistance used for my ebay supergun (neo jamma). I do have a scope, but I have not used it much to read it properly. If using scope, what level should I dial it to? Are there built in impedance (doesn't appear there is) so that I won't accidentally dial it too high while in use to fry the OSSC?
2. Does powering the HAS without connecting to PCB fry the HAS?

*edit* I hooked up my scope and had the screen on the RGB page after crosshatch, I found the following.

if I adjust the dial to 500ohms, I get 1.28v peak to peak from the video signal. I think that's too high? I adjusted it til it's 680mv, and I measured the resistance to be about 900ohms. If I measured between the middle pin and the pin closer to the DB15 connector.

I measured my ebay supergun too, it uses a 500ohm pot, and the Vpp is jumping all over the place. it varies between 1.44v - 2v sometimes, other times it goes up to 2.8v. Is this going to kill the OSSC? Probably off topic.
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Still trying to figure out how to set the pot properly. I don't want to end up with a fried OSSC because the dial is set to high. Anyone else know how?

One of the feature says "
  • RGB video driver - 75 ohm signal output; The brightness regulation is more precise now and it should be right for most PCB games out-of-the-box - the potentiometers are used mostly to fine tune the brightness (they have a limited adjustment range); It's safe - you can get the right Vpp for games with both weak and strong RGB signals (it shouldn't output anything above 1.5Vpp even if the game's signal is *extreme case* 5Vpp)."
But isn't 1.5Vpp too high? I thought it should be 680mV. Please educate me.
 
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RGB said:
@rcboosted - it's ~0.7Vpp for most games out-of-the-box. 1.5Vpp is the worst case scenario with 5Vpp video signal amplitude (whereas it's usually 3-4Vpp) and the pot fully open. Still, that's well within tolerance of the THS7353 buffer used in the OSSC.
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Thank you RGB for the information and confirmation.
 
28D07701-444A-4A2C-9567-13208D75421F.jpeg

Can someone tell me if this wiring looks correct? I’m worried to turn on my HAS and hook up a game before I’m sure this is correct.
 
@Hoosiershadow it depends on what voltage +v2 and v3 are for that power supply (probably a sticker/label on it). one is probably 12v and the other -5v.

and also depends how you’re connecting the wires to the HAS side! I assume black is ground and red is +5v but without seeing those wires I can’t confirm.
 
ekorz said:
@Hoosiershadow it depends on what voltage +v2 and v3 are for that power supply (probably a sticker/label on it). one is probably 12v and the other -5v.

and also depends how you’re connecting the wires to the HAS side! I assume black is ground and red is +5v but without seeing those wires I can’t confirm.
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Yeah man, post the full connection and we'll be able to tell.
 
Question!

I'm planning on grabbing a SEGA Naomi system with JAMMA IO converter. What's the deal with power etc. when hooking this up to the HAS? Since the board + GD-ROM has its own power supply... do I need to worry about anything in terms of the power that's supplied via the JAMMA connector on the HAS? Or does this just power the IO board itself so nothing to worry about?
 
The JAMMA-compatible power supply unit would only power the IO since it doesnt have the 3.3V needed to power the NAOMI. if you’re using a JVS IO like the Capcom IO, you’ll need two PSUs; one for the HAS which will power the IO board and another JVS-compatible PSU for the NAOMI.

There is a way to power everything using just one PSU. Get a Mean Well QP-150 which has the DC lines for JAMMA, (5V, 12V, and -5V) and also has the DC lines for JVS, (3.3V, 5V, and 12V). You’ll just need to build a custom harness for the NAOMI.
 
kikaso said:
if you’re using a JVS IO like the Capcom IO, you’ll need two PSUs; one for the HAS which will power the IO board and another JVS-compatible PSU for the NAOMI.
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Are you sure about the Capcom IO? I thought the Capcom IO converts everything between Jamma and the Naomi, even power. But it has been a while, I could be wrong. I never used one with GD-Rom, does that make a difference?
 
KeeseMan said:
Are you sure about the Capcom IO? I thought the Capcom IO converts everything between Jamma and the Naomi, even power. But it has been a while, I could be wrong. I never used one with GD-Rom, does that make a difference?
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Capcom IO has 3.3V for NAOMI but doesn’t provide enough power for GD-ROM drive or booting from Net Dimm. You can use Capcom IO for power if you’re just using cartridges on NAOMI.
 
kikaso said:
Capcom IO has 3.3V for NAOMI but doesn’t provide enough power for GD-ROM drive or booting from Net Dimm. You can use Capcom IO for power if you’re just using cartridges on NAOMI.
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That was it. I remember now, thanks for clearing that up. :)
 
Thank you for interest! I had to temporarily close the order form, otherwise there would be too many orders to process. It should be up again in around a week!


the Goat said:
Can you summarize the changes from v4 to v4.1?
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- the microcontroller is in DIP case again, so that it can be easily replaced.
- instead of multiple switches all over the place, there's a DIP switch on the bottom that allows to: disable JAMMA output for buttons 4, 5, 6; toggle LPF; set TTL/75R CSync

nonosto said:
happy about your come back. Extender avallable soon.
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That's planned too, but the focus is on the HAS (and RECO) right now, thanks!
 
RGB said:
I know many supergun builders add the JAMMA-MVS switch as a feature.. and it may seem controversial, but I don't believe it's needed at all, and it can cause more harm than good. My reasoning for this is as follows:

- On the other hand, connecting a JAMMA PCB to a MVS stereo set supergun or a MVS cabinet by mistake, can damage the amp on the PCB.

- The only feature one will miss when connecting a multi-cart MVS to HAS, is the TEST button, because it's mapped to a different pin on the edge connector in the multi-carts models. To remedy this, I can additionally map the TEST button to that pin in the next HAS revision.
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Sorry to bring up this old post, I quoted a snippet of it. Would setting the HAS to Stereo mode hurt a MV1B or MV1C PCB? It's not clear to me if MV1B or MV1C in particular will be damaged or not if HAS is set to Stereo (MVS) mode.

Regarding the test button, can the test button on the HAS 4.1 be mapped to the test button on MVS 2 slot or 4 slot? If so, how. Trying to figure out what to do with the test button the on 2 and 4 slots.
 
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