Naomi Jvs issue

[nipple]

hey I’m in the weeds, I have been trying to get my dynamic golf panel working. It has the encoder board mounted to the under side and is powered, red light is on.

I know it needs a second io board for key inputs. But for the life of me I cannot get a second jvs board to work, only the last one in the daisy chain will work.

Has anyone had this before?

I have tried the sega jamma io both types, and have tried 2 type “2” io boards all linked in various chains. Even tried 3 boards linked. But in the test menu nothing ever showed except the last board.

All io boards work individually. Could it be my Naomi? I don’t have a second one to test. I do remember seeing multiple nodes show in the past in test menu. But not this time. Have tried for about a week.

Cables are the genuine Sega beige NOS usb cables and work with 1 board.

Any advice or tips I can try.

The dynamic golf boots to an IO board not acceptable screen showing the encoder board as node 1 and nothing for node 0.

I’m stuck!

 

[nipple]

Update!!

I have been trying every combination known to man to get this working. All to no avail, so I decided to try and learn what was wrong rather than be a cave man and whack it .

I found a really good manual on line that explains the JVS protocol and how it works, including the daisey chain and subsequent nodes.

I found that the pin 1 on the usb Type A plug is the sense wire and that it goes high and low to detect nodes.

So I checked my Naomi 1 filter board usb connector and it was good to the filter board. I then traced where it went on the filter board USB connector back to the main Naomi pcb. It ends in the cartridge opening. Where I traced it to a little black ic that is all burned up.

Bingo no sense signal to tell my nodes what to do.

Can anyone tell me what part no those little Ic’e are?

Hopefully I can change it and still have a working Naomi.

Also does anyone have a clue what caused it?

Cheers

 

[shelcoof]

Wow those ICs were burned up?
I've heard NAOMI are prone to burning up chips if the voltage is slightly too high
Ever since reading about that I've only used an ATX PSU to power my NAOMI

 

[nipple]

Hey guys,

Does anyone know what the part is that is burnt? It has “DA 18” on the pcb next to it?

I’m guessing Diode array. But what spec?

Cheers

 

[djsheep]

Paging @Big_P Big_p

 

[Mrhide]

nice debugging.
This should perhaps help:

 

[Big_P Big_p]

IMP11 high speed switching diode array in SOT23-6

 

[nipple]

@Mrhide @Big_P Big_p

Thanks guys. Appreciate it, now for my 8th digikey order on a month .

Trying to rack up the free shipping is killing me . I’m not sure there is anything left to buy.

Hopefully that gets the job done. I just need to try and find out what caused it to go now. Bad io board I’m assuming. I think maybe my trackball encoder as all worked before then.

Will report back. Appreciative of the help once again.

 

[nipple]

Ok so I changed the diode array.

But I still have an issue, I think whatever blew up the diode array may have taken out something else deeper in. I will try and follow the circuit back a bit further. The solder around ADM485 chip looks manky, like it has been changed or worked on previously. Funny thing is the Naomi works perfectly with games that need only 1 IO board. I might have to double check my soldering but it looks good under my aliexpress microscope

I also checked the voltage on the usb sense line on my IO boards and they are all at 5v. So, I don't think it's them.