Solved: Naomi1 Refuses to Detect any JVS I/O

[rfsup]

Purchased a Naomi from eBay that refuses to detect any JVS I/O. No matter what I try, I see "NO JAMMA I/O BOARD" in the JVS TEST menu. Appreciate any input that might lead to a breakthrough.

Things I've tried (dozens of times) --> And the result

• Boot without any cartridge --> JVS Test Menu reads "NO JAMMA I/O BOARD."
• Boot with a cartridge --> JVS Test Menu reads "NO JAMMA I/O BOARD."
• Netboot MVC2 --> Game boots, Then: "ERROR. JAMMA I/O BOARD NOT FOUND"
• Netboot DoA2 --> Game boot, Then: "This cabinet has no new-jamma I/O board."
• Tried changing the filter board -> JVS Test Menu reads "NO JAMMA I/O BOARD."

JVS I/O Devices I've tried with the scenarios above

• rPi2 running openjvs using RS485 and PS4/PS3 controllers (weirdly, I saw JVS Test detected ONE time out of hundreds of boots)
• mp07-1ona-us using PS4/PS3 controllers
• Tuscon Logic board (with nothing connected)

Notable facts about the Naomi

• RAM Test shows IC22 BAD. all other chips good. (See attached)
• On the board I can notice two modifications I assume are not factory (See attached)
• Using ATX Power Supply (this one)
• Using multi-bios version H

 

[chacal231077]

Hi!

Change IC 22

 

[rfsup]

Hi!

Change IC 22

Do you know if IC22 is directly related to the boards ability to interface with JVS? I'm nervous to attempt that chip swap if it's unrelated to the JVS problem.

Maybe I have to replace it eventually anyhow. Just trying to be systematic before I attempt the micro soldering.

 

[Brettster]

Is the blue on the 2nd picture a light or corrosion on the PCB?
looks a bit nasty around the caps in that area, IC22 might be fine and something else is the main issue.
worth checking continuity etc first

 

[nam9]

Have you checked the USB port to see if all pins are present and correct?

 

[rfsup]

The blue light ended up just being part of the flash. Turned out the USB pins were fine.

Root cause here ended up being a little silly. Two problems.
1) I had bought two different rs485 adapters and apparently neither of them were performing to spec. Had someone recommend a third adapter that immediately worked.
2) I was booting MVC2 to test. I received the no jamma found error consistently until I plugged in a second controller. I'm assuming the game requires two controllers in order to boot.