NAOMI Out of Service
Tuesday August 12, 2025
I had the brilliant idea to hook the NAOMI up to the Versus City yesterday, since Virtua Tennis is one of the few games that supports the winner lamps and billboards. It took a little effort to get the game up and running, mostly because I forgot how to netboot a game from my laptop.
It turns out I’m missing a wiring harness, so the billboard can’t communicate with the game board. I’ll save the details for the “Versus City Log” post later.
After moving the NAOMI back to the Blast City, I kept getting “Error 31” upon starting any game. I read online that the netDIMM cart could need to be reseated, or that it could be bad RAM. I reseated the cart as well as the RAM inside the cart, just for good measure.
Now the NAOMI won’t boot at all. I have no idea what I did, but I really wish I just left everything alone. I called Ken from irepairsega, assuming I fried something after hooking it up to the Versus City.
Some Context
Sometimes I catch myself yapping about this stuff with the assumption that everyone already knows what I'm talking about. A netDIMM cartridge is like a regular NAOMI game cartridge, but blank. It has an Ethernet port on it for loading games upon startup. The RAM where the game is stored is regular (old) desktop RAM, and can be popped out just like on a desktop motherboard. I was worried that I may have fried something because the NAOMI is very sensitive to incorrect voltages coming from the power supply. I was worried that my Versus City power supply was not configured correctly, and maybe the netDIMM was ruined as a result.
He suggested removing the netDIMM’s plastic case and connecting it directly to the NAOMI motherboard. In the process of disconnecting the NAOMI so that I could give that a try, I yanked a wire from the power extension cable. I don’t think repairing the power cable should be too difficult, but it definitely sucks having to do a repair just to attempt another repair.
I figured I had done enough damage, so I hooked up the MiSTercade and called it a day. Lesson learned, for real this time: DON’T MESS WITH ANYTHING.