Sega-Naomi

In a nutshell, the symptom is this: drive doesn't spin properly and laser goes all the way to outside and then bangs against the edge over and over.

Cables are fine, gets power, etc. returns expected errors with cables unplugged, and gets error 25 when drive is connected(unable to communicate with gdrom I believe which would make sense as it obviously isn't working right)...so in other words the naomi knows it's there just can't get anything from it because of the drive/laser issue...

After playing around with it a while I'm thinking it's the control(top) board that needs replacing...sound right? TIA!

can be either the lens or the servo board,if you have model 610-0617 then andygeezer has drop in repacement units

http://triplemoonstar.brinkster.net/seg ... subcat=115

I thought Andy said that error's 20-25 are purely dimm board related.

gehrig wrote:I thought Andy said that error's 20-25 are purely dimm board related.

nah,pretty sure error 24 and 25 are solely related to the gdrom hardware-of course i could be wrong but i have had both those faults before and they were gdrom based problems

pretty sure 24 is the lens itself and 25 is the board

Hey grantspain! Didn't know you were here too

Anyhoo, not the laser cause I replaced that with one from an old dc I had...even confirmed the one that came outta the naomi gdrom worked by putting it in the dc and booting up skies of arcadia...

so I was fairly certain it was the board but as you know, I always like to have second opinions before I do anything major...

anyways, great to know there are boards available as replacement...especially since that's exactly the model I have

Thanks for the input!

Oh! and I believe you are correct; to the best of my knowledge, 24-25 are related to the gdrom unit itself 9 times outta 10.

hello,

i am everywhere :smt005

if the gdrom is the 610-0617 you can swap over the entire dc unit

If it is a 610-0617-01 and you get Error 24 then the GD-ROM drive is scrap..



Error 25 can be fixed with a lens/motor change.



Error 24 can be fixed on 610-0617 by buying a complete lens unit.

I found a new board and am happy to report that fixed the gdrom unit.

I left the dc lens,etc in it just to be safe(but mostly because I'm too lazy to swap it back) and the gdrom and dimm are working fine.

but now I gotta fix the i/o card :-/ It's not found when the game boots...but I can get it to work with the wrong power connection(the gdrom one) and a cartridge....odd...well, there is a chip that is obviously broken on it(ic11 I believe) so that might have something to do with it I suppose...

lol! it's always something! anyways, thanks for helping!



[UPDATE-07/10/08]

Just wanted everyone to know the gdrom drive is still working fine. The I/O card not so much-lol!

I just took delivery of a GD-ROM drive and DIMM board and I accidentally plugged in the I/O power connector to the GD-ROM drive instead of the GD-ROM power connector. Its the same connector physically as a GD-ROM connector but wired differently, +12v and +5v are reversed on the GD-ROM power compared to the I/O power. Nice one Sega... NOT.



Basically I fried my GD-ROM drive and possibly the DIMM board too. Now I get exactly the same error as the original poster (20 something) and the same behaviour (HEAD goes to outside and buzzes and tries to keep going). The laser still lights up and moves so the head itself might be OK.



Because the OP sounds like he has exactly the same symptoms my bet is that he (or whoever he got his hardware from) did exactly the same thing at some point.



I happen to have a spare known good DIMM module so I swapped that in with that same GD-ROM drive and still got the same error/behaviour so making that mistake does definately fry the drive (at least). I may also have fried the DIMM board too as its memory test reports bad memory. I say 'maybe' as it was just sent to me and I hadn't run the memory test before I fried the drive so it possibly could have been bad already.



The point of this post is to:

1) admit I'm a dumbass for not double-checking everything before powerup

2) Warn everyone to be REALLY CAREFUL to not mix up the I/O and GD-ROM power connectors. They are physically identical so its very easy mistake to make (especially if you have your GD-ROM right next to your I/O card and like me you have a wiring loom with a spare I/O power connector right next to the GD-ROM) but it will permanently kill your GD-ROM and possibly DIMM board too.

You can get a replacement board from Andy...just check your gdrom's model # first to be sure it's the right one.

As for the DIMM, have you tried re-seating all the cards in it yet? When I first got mine, it had memory errors, but re-seating everything fixed it...just something to try...no promises.

justniz wrote:I just took delivery of a GD-ROM drive and DIMM board and I accidentally plugged in the I/O power connector to the GD-ROM drive instead of the GD-ROM power connector. Its the same connector physically as a GD-ROM connector but wired differently, +12v and +5v are reversed on the GD-ROM power compared to the I/O power. Nice one Sega... NOT.



Basically I fried my GD-ROM drive and possibly the DIMM board too. Now I get exactly the same error as the original poster (20 something) and the same behaviour (HEAD goes to outside and buzzes and tries to keep going). The laser still lights up and moves so the head itself might be OK.



Because the OP sounds like he has exactly the same symptoms my bet is that he (or whoever he got his hardware from) did exactly the same thing at some point.



I happen to have a spare known good DIMM module so I swapped that in with that same GD-ROM drive and still got the same error/behaviour so making that mistake does definately fry the drive (at least). I may also have fried the DIMM board too as its memory test reports bad memory. I say 'maybe' as it was just sent to me and I hadn't run the memory test before I fried the drive so it possibly could have been bad already.



The point of this post is to:

1) admit I'm a dumbass for not double-checking everything before powerup

2) Warn everyone to be REALLY CAREFUL to not mix up the I/O and GD-ROM power connectors. They are physically identical so its very easy mistake to make (especially if you have your GD-ROM right next to your I/O card and like me you have a wiring loom with a spare I/O power connector right next to the GD-ROM) but it will permanently kill your GD-ROM and possibly DIMM board too.