Nintendo PCBs not booting correctly on Windy II (Jammafier v1/v2)

[jbrochu1985]

Hi everyone, I’m looking for some help diagnosing a compatibility issue with Nintendo arcade boards on my cabinet setup.


I have two Nintendo PCBs — Donkey Kong (2-board stack) and Mario Bros — both using the PCB Junkie Nintendo-to-JAMMA adapter.
I own both a Jammafier v1 and a Jammafier v2 (the one with the integrated tri-sync support).

Symptoms​

• Donkey Kong: no boot at all on the Windy II (no video, no startup signs).
• Mario Bros: boots but shows severe graphical glitches (see picture).
• Both boards work perfectly on a HAS Supergun → Retrotink 5X → consumer TV.

My cabinet is a Konami Windy II with the Toshiba chassis.
All my other JAMMA and JVS PCBs work flawlessly, including ones using PCB Junkie adapters (Galaga, System 16, Nibbler).
I also have a Nintendo Vs. System PCB, and that one has never given me any issues on the same setup.

Power Measurements​

Measured at the JAMMA edge with nothing connected (pre-load values):

• +5V = 5.5V
• +12V = 12.2V

I know these are high without a load, so I usually dial down once a PCB is connected — but mentioning it here in case Nintendo boards are more sensitive to the initial surge or the Jammafier handles power differently compared to the HAS.

Questions / Possible Causes​

• Could Donkey Kong / Mario Bros be sensitive to overvoltage at boot, especially through the Jammafier?
• Sync level mismatch? Nintendo’s early hardware uses oddball composite sync, and the HAS might be more forgiving than the Jammafier.
• RGB inversion / attenuation differences between the HAS and the Jammafier?
• Could the Windy II’s Toshiba chassis be less tolerant to early Nintendo sync levels or polarity?
• Grounding or edge connector alignment issue specific to the 2-board stack design?

I’m trying to figure out whether this is:

1. a Jammafier quirk,
2. a Windy II compatibility issue,
3. or something inherent to early Nintendo PCBs.

Any insight would be greatly appreciated.

 

[jamesv833]

I’m not familiar with that cabinet but maybe the PSU doesn’t supply -5V.

 

[jbrochu1985]

I’m not familiar with that cabinet but maybe the PSU doesn’t supply -5V.

Here are the voltage measurements I took. I checked the Jammafier with no load, then with Mario Bros connected, and I also compared it to my HAS Supergun with the same board.


Jammafier (no load):

• +5V: 5.499V
• –5V: –5.441V
• +12V: 12.31V

Jammafier (with Mario Bros connected):

• +5V: 5.2V
• +5V (2nd test point): 5.2V
• +12V: 12.20V
• –5V: –3.3V

HAS Supergun (with Mario Bros):

• +5V: 5.034V
• +5V (2nd test point): 5.0V
• +12V: 14.52V
• –5V: –4.62V

So the HAS seems to deliver a cleaner and more stable +5V under load compared to the cabinet PSU → Jammafier combination, which might explain why Donkey Kong and Mario Bros behave normally on the Supergun but not in the Windy II setup.

 

[jamesv833]

Maybe just one side of the harness has -5v populated and you can add another or use larger wire. Could be a limitation of the PSU supply current as well.