Problem with naomi speed/ video output

[maplejava]

New poster here

I'm currently testing out this NAOMI I have, and tested it out on a friend's net city cabinet.

Swapping it in the cab to test, It wouldn't output any video, but it seemed that sound worked, as I was able to hear the Naomi opening, but for some reason, there was a large amount of delay between the first sound of the boot followed by the other part of it.

Ive also tried swapping in the cart to have it have no ram expansion, as well as with a cart of powerstone 2 (Which worked on the other naomi that was in the Net city prior). And either the speed/power of the naomi was too slow to even boot up the intro, or it didnt boot up at all, since i couldn't hear the capcom attract sound.

Things I've also tried;

Swapping dipswitches, from setting the first switch to bottom/top - no difference, still no video, and large delay between the naomi booting sounds

Swapping the chip that came with the naomi for the multi region bios chip - also no difference, nothing noted at all

Making sure the internal battery still had juice, even it if wouldn't affect it

A friend also suggested that maybe the 9 pin in the video output got fried, suggesting the 9 pin on the video out

 

[djsheep]

What resolution is the monitor in your NNC?

Make sure your monitor is adjusted right if there's any adjustments, then flip DIP 1 to suit 15KHz or 31KHz

 

[RealMFnG]

Good lord. That quite possibly is the most mint condition Naomi I have ever seen.

 

[twistedsymphony]

tested it out on a friend's net city cabinet

Does your friend's Net City Cabinet work? do they have their own NAOMI unit running on it to confirm resolution and configuration? it sounds like your friend has a Net City with a Powerstone cart that works, is that correct?

for some reason, there was a large amount of delay between the first sound of the boot followed by the other part of it.

If you're using the DIMM board there can be up to a 1 minute wait for the game to load after the NAOMI splash screen.

And either the speed/power of the naomi was too slow to even boot up the intro, or it didnt boot up at all, since i couldn't hear the capcom attract sound.

There are a number of things that could have prevented it from booting, without video on the screen it's impossible to say

Things I've also tried;

Swapping dipswitches, from setting the first switch to bottom/top - no difference, still no video, and large delay between the naomi booting sounds

A friend also suggested that maybe the 9 pin in the video output got fried, suggesting the 9 pin on the video out

Based on your description it sounds like the NAOMI is booting but there is an issue with the video output and possibly a second problem preventing it from loading the game.

If you're using an original BIOS (not a multi-bios) then your first step will be ensuring the dips are set properly:


A Net City assuming it has an original monitor should work in both 15K and 31K modes... though 31K is preferred.

Pin 9 on the video cable inside of the Net city should be removed. The reason is that the Net City monitor links this pin to Ground and the NAOMI links this pin to 5V (obviously this is bad) from the factory Sega included a VGA cable with pin 9 removed, but people may have swapped in a non-original cable with pin 9 in place. This can cause the cable to get hot and obviously cause other issues as well.

Once you've got the dips set right and verified that the cable is good with pin 9 not set. if you're still having issues, the next thing I'd do is take an Oscilloscope and check the video sync pins on the VGA connector for signs of an appropriate 15K or 31K signal. If you don't have a scope the next best thing would be to disassemble both your bad NAOMI and your friend's GOOD NAOMI and swap the filter boards (the PCB on the side of the case with all of the connectors). Then you can see if your NAOMI works with your friends filter board and if your friends NAOMI works with your filter board and help narrow down the fault.

 

[maplejava]

What resolution is the monitor in your NNC?

Make sure your monitor is adjusted right if there's any adjustments, then flip DIP 1 to suit 15KHz or 31KHz

My friend mentioned it was a 15k

Does your friend's Net City Cabinet work? do they have their own NAOMI unit running on it to confirm resolution and configuration? it sounds like your friend has a Net City with a Powerstone cart that works, is that correct?

Theirs worked. We tested the cab with the naomi that was already in it, which ran the game fine, no delays on sound either, then swapped it out for the naomi I own, which had the issues stated.

Also after reattaching the cables back into the original naomi, it also ran as normal too.

If you're using the DIMM board there can be up to a 1 minute wait for the game to load after the NAOMI splash screen.

It took much longer than the naomi that was inside. I believe we waited around 5-10 minutes before turning it off.

A Net City assuming it has an original monitor should work in both 15K and 31K modes... though 31K is preferred.

Pin 9 on the video cable inside of the Net city should be removed. The reason is that the Net City monitor links this pin to Ground and the NAOMI links this pin to 5V (obviously this is bad) from the factory Sega included a VGA cable with pin 9 removed, but people may have swapped in a non-original cable with pin 9 in place. This can cause the cable to get hot and obviously cause other issues as well.

Once you've got the dips set right and verified that the cable is good with pin 9 not set. if you're still having issues, the next thing I'd do is take an Oscilloscope and check the video sync pins on the VGA connector for signs of an appropriate 15K or 31K signal. If you don't have a scope the next best thing would be to disassemble both your bad NAOMI and your friend's GOOD NAOMI and swap the filter boards (the PCB on the side of the case with all of the connectors). Then you can see if your NAOMI works with your friends filter board and if your friends NAOMI works with your filter board and help narrow down the fault.

- Mentioned about the dipswitches, the naomi inside the netcity was set to 15k. Ive already tried it on both 15k and 31k mode, and I saw no difference in the sound, with still no video either.

-I believe the VGA cable that is used on the netcity is an original one, with the beigeish light gray color and all, especially since if it had the 9 pin on it, it might've not been able to run the naomi that was inside the machine.

-Ill try swapping the filter boards to see if that works, same for checking power signals on the vga too

 

[jassin000]

Good lord. That quite possibly is the most mint condition Naomi I have ever seen.

I was thinking the same, like... If you scrap it because something is fucked with the board, I'm looking for a nice case.