Sega Naomi 1 with Capcom I/O Freezing

Pablo_the_Mex

New Challenger
Hey Guys,

I swear I searched. I got one "american" cab with new Happ power supply, Naomi 1, capcom I/O and MvC2 cart. Worked fine for a while, but now what happens is the game can freeze at extremely random intervals. It can be right after the "loading game" screen, or after an hour.

I suspect the capcom I/O, for some reason the 5v does not go through it. Using my multimeter all I can get was a 3.27. Tried the I/O on my astro cab, and I get all the proper readings (5, 12, 3.3). Turned up the 5v on the power supply, same deal.

I can get 5v off the jamma connector. Is there something I can do to "tighten" the connection on the jamma edge? This is the best I could do in terms of troubleshooting.

Anyone else have Naomi 1 games freeze like this? Is it even a power issue? Any input is appreciated.

Thanks.
 

Tyranix95

Giga Shock!!
Since your Happ PSU is new: The likely suspect is the CAPCOM I/O.

I have a Happ power supply, Naomi 1, capcom I/O and CvS cart--And get the proper power readings with no game play problems.

And, my buddy has a Happ power supply, Naomi 1, capcom I/O and MvC cart--And he gets the proper power readings with no game play problems.

And, sounds to me, like when you test your MvC setup with a different I/O, your NAOMI setup works fine.

But, the only want to know for sure is to test your setup with another CAPCOM I/O.
 

Pablo_the_Mex

New Challenger
Since your Happ PSU is new: The likely suspect is the CAPCOM I/O.

I have a Happ power supply, Naomi 1, capcom I/O and CvS cart--And get the proper power readings with no game play problems.

And, my buddy has a Happ power supply, Naomi 1, capcom I/O and MvC cart--And he gets the proper power readings with no game play problems.

And, sounds to me, like when you test your MvC setup with a different I/O, your NAOMI setup works fine.

But, the only want to know for sure is to test your setup with another CAPCOM I/O.

Well the I/O works fine when I put it in another cab. That is why I was thinking it was the either the PS or something in the JAMMA wiring.
 

BIGTIME

Galford's Armourer
Could be bad buffer chips in the game. I had a Giga Wing 2 cart do this to me and I had to send it off to Ken at http://www.irepairsega.com/conact_info.html to fix it.

+1 on this naomi carts were made with substandard fairchild buffers that according to Ken are like a time bomb. Usually carts just die but I suppose the buffers could cause your symptoms. The best thing ti do would be to consult Ken he is definitely the authority on sega arcade hardware repair.
 

Tyranix95

Giga Shock!!
If you think the MvC cart is causing your problems, then put a known good test cart on your NAOMI setup with the CAPCOM I/O. Run it in your cab: See if your NAOMI setup freezes up.

---

Another option: Test your NAOMI with a SUN psu. The sun has voltage pots to adjust the +5V & +3.3V lines. Set the power to lines to 5v and 3.3v dead on (voltage measured at the power connectors on the Naomi Filter board).

---

A bad cart should not change the voltage comming from the I/O to the Naomi Filter board; however, either a bad I/O<>PSU powoer set-up should.
 
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Pablo_the_Mex

New Challenger
I got two cabs giving me the same problem, but only one I can test. The other is at a friend's crib. Both are Naomi 1 with MvC2 carts.

The one at home works fine when I power it with a sun PSU. The other I will try another cart and see if it still freezes. That is why I suspect wonky power. These goddamn american cabs have been converted 7 times by the time I get to them.
 
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skate323k137

Giga Shock!!
Can you clarify this:

I suspect the capcom I/O, for some reason the 5v does not go through it. Using my multimeter all I can get was a 3.27. Tried the I/O on my astro cab, and I get all the proper readings (5, 12, 3.3)

Are you checking the output of the capcom I/O where you'd hook it to the NAOMI to power the naomi? If theres an issue with the 5v passing through to that connector, or the 3.3 doesn't read right, you may have a bad IO or bad voltage regulator(s) in the capcom I/O. If the power output of the I/O is OK in other cabs, then it's probably the power supply you're using. Since JAMMA PSU's are a dime a dozen, I'd change that first.
 

Tyranix95

Giga Shock!!
The Capcom I/O also converts +5V to 3.3V, for the NAOMI. So, +5V, +12V passes thought, but, 3.3V is converted on the I/O.

(The big problem with the C-I/O is that it only supports the Naomi CN1 power plug, which is not enough to power a either a NET/DIMM or GD-ROM expansion setup.)

The C-I/O CN1 can power the a Naomi cart setup just fine--if everything is working ok.

So, you may also want to meter the power at the C-I/O connector and make sure the C-I/O is putting out +5.0 and +3.3V.

Also, you may want to meter the +5V (Jamma Harness) power lines powering the C-I/O. Make sure the C-I/O is getting enough power. The C-I/O should be getting +5.00V~+5.10V. Do not exceed +5.25V.

And if you do adjust the voltage, make sure the C-I/O +5V input voltage does not exceed the 5.00~5.10~5.20 range; and, the C-I/O output voltages does not exceed the +5.0V, +3.3V mark.

NaomiPowerPinout.gif


1. Not Used.
2. +3.3V (orange)
3. +5V (red)
4. +12V (yellow)
5. GND (black)

capcom-io-board.jpg

pinout.png
 
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Pablo_the_Mex

New Challenger
Can you clarify this:

I suspect the capcom I/O, for some reason the 5v does not go through it. Using my multimeter all I can get was a 3.27. Tried the I/O on my astro cab, and I get all the proper readings (5, 12, 3.3)

Are you checking the output of the capcom I/O where you'd hook it to the NAOMI to power the naomi? If theres an issue with the 5v passing through to that connector, or the 3.3 doesn't read right, you may have a bad IO or bad voltage regulator(s) in the capcom I/O. If the power output of the I/O is OK in other cabs, then it's probably the power supply you're using. Since JAMMA PSU's are a dime a dozen, I'd change that first.

I am checking from the I/O connector that goes into the Naomi. Had a friend of mine recently re-do the powersupply, but it could just be the extremely crappy jamma connectors/wires.

The Capcom I/O also converts +5V to 3.3V, for the NAOMI. So, +5V, +12V passes thought, but, 3.3V is converted on the I/O.

(The big problem with the C-I/O is that it only supports the Naomi CN1 power plug, which is not enough to power a either a NET/DIMM or GD-ROM expansion setup.)

The C-I/O CN1 can power the a Naomi cart setup just fine--if everything is working ok.

So, you may also want to meter the power at the C-I/O connector and make sure the C-I/O is putting out +5.0 and +3.3V.

Also, you may want to meter the +5V (Jamma Harness) power lines powering the C-I/O. Make sure the C-I/O is getting enough power. The C-I/O should be getting +5.00V~+5.10V. Do not exceed +5.25V.

And if you do adjust the voltage, make sure the C-I/O +5V input voltage does not exceed the 5.00~5.10~5.20 range; and, the C-I/O output voltages does not exceed the +5.0V, +3.3V mark.

NaomiPowerPinout.gif


1. Not Used.
2. +3.3V (orange)
3. +5V (red)
4. +12V (yellow)
5. GND (black)

capcom-io-board.jpg

pinout.png

I did adjust the knob to up the 5v, since I am still suspecting power to be the issue. However even after upping it I only got a 3.27 reading, nothing for the other two lines.

Thanks for the input guys it really helps to narrow down the troubleshooting.

I will have my friend re-check the power situation on my cab at home, and on the other have my friend swap the cart to see if it still freezes up. It sucks having cabs at different locations that need troubleshooting.
 

Xian Xi

JammaNationX,
See post 11.

It's a straight tough power cable.

Post 11 doesn't help much. I'm trying to make one of these for a friend which is why I have no idea where the other end of the +12v line goes. According to the pinout in post 14, +12v line is just floating as it doesn't connect to the 6 pin connector.
 
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