Sega-Naomi

Hello all,



I've got a Naomi, just running carts, with the Capcom IO on a New Astro City.



The problem is that the Naomi is inconsistent with booting up. It will go great for a while then suddenly will only boot up once in like 10 tries, maybe more. (currently it will not boot up for me at all)



I tried it in my second cabinet, same issue.

I checked the voltage when the Naomi is on and it sits at +5.05v.

The Naomi fan comes on, nothing on screen though.

I've tried multiple games.

I plugged a CPS2 game into this cab and it booted fine.

The Naomi has the region switch installed, I tried 2 different regions, no change.



The last time it booted up (about 15 tries ago) it was without a cart and it booted to the white Naomi screen, I shut it off, plugged in a cart and no boot.



Not sure where to start, is there a good trick to try and isolate if the problem is the Naomi or the IO? Anyone familiar with the likely causes of this issue?



thanks!

unplugged it all and tried again and it booted up again.... so weird.



I then jiggled all the wires to see if there was any change and no change, letting it run right now to see if I can figure it out.



VERY open to ideas on how to isolate this.

i'm having the same problem so hopefully someone will be able to help us out

srabelpawz wrote:I'm having the same problem so hopefully someone will be able to help us out

really? so strange.... got home after going out for drinks, touched NOTHING at all since it was working other than turning it off and it won't boot, 3 tries in a row. Before I tested the voltage across the +5 I assumed it was low voltage, but I currently have no ideas....

you will find stated quite often by myself and others that for a naomi mobo to run perfectly you need the +5 to read 5.05-5.10volts AT THE MOBO PLUGS,also make sure your 3.3 is set at the correct level

do not read at the jamma

Also make sure that everything is as clean as possible: I cleaned my Naomi2 mobo recently, and had no problems since then.

grantspain wrote:you will find stated quite often by myself and others that for a naomi mobo to run perfectly you need the +5 to read 5.05-5.10volts AT THE MOBO PLUGS,also make sure your 3.3 is set at the correct level

do not read at the jamma

this makes sense, didn't think how the Capcom IO could take some of the juice, thanks.



I assume I use the volt meter at the little labeled silver pins above the cables?



Cageman, will give it a good cleaning too, thanks!

meter at the mobo input plugs not the i/o

white is ground,yellow is +5 and brown is 3.3

grantspain wrote:meter at the mobo input plugs not the I/o

white is ground,yellow is +5 and brown is 3.3

ok got it...



3.26v, 5.08v, and 11.87v

scogon wrote:

grantspain wrote:meter at the mobo input plugs not the I/o

white is ground,yellow is +5 and brown is 3.3

ok got it...



3.26v, 5.08v, and 11.87v

should be o.k tbh,maybe you have a dirty pin on the cart