Odd Naomi, DIMM and Compact Flash reader issues: ERROR 21!!

TSXGuy

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Hey guys, thanks for reading my post/thread. This one is pretty tricky. I have a Sega Blast City that was working pretty well with my setup which is as follows:

Sega Blast City
Naomi 1 MB
DIMM
Compact Flash reader
Capcom I/O

So here is the deal, a few of my games have worked and most all have been Atomiswave. However, even now some of the Atomiswave games are not working. I have one CF game that I got that always works. A few others also work fairly consistently. However, when I try to download any Naomi ROM from a good source, the Naomi acts funky and starts checking memory at 27%. Then, when it does finally go through multiple uploads and memory checks I get ERROR 21. As I recall, when things were going fairly smoothly, the Naomi screen would pop up, the game would load, then you would have 2 memory loads before the game started. But, it's no longer doing that. I was able to get the reliable compact flash card to start but it still started on the memory instead of first loading the game.

I know that of the ROMS/Bins that I am using they can't all be bad so what do you think the issue is? I unplugged the Naomi cables from the cab, and unplugged both the SCSI cable and the USB cable and then reconnected. Same issue: ERROR 21.

So does anyone have a guess as to what's the culprit? These are always hard when you can get a game or two to load but not others. Could it be the compact flash card? I bought Transcend and SanDisk which have both worked. I don't know the name of the card that always works but I can check.

Thanks for your help on this. I'm leaning towards a faulty DIMM but am not sure. For the record, I read this entire thread:

http://www.neo-geo.com/forums/showt...ME-IS-NOT-ACCEPTABLE-BY-MAIN-BOARD-quot/page2

Unfortunately, doesn't seem apples to apples with my issue. Though there were some similarities.
 

Lemony Vengeance

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These DIMMs are power hogs.. are you using the blast PSU to send power to the naomi, or do you have a sun PSU?
 

Neodogg

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Isn't that the error when the DIMM needs to be reseated?
 

madman

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Isn't that the error when the DIMM needs to be reseated?
According to AO:
Error 21
Display: THIS GAME IS NOT ACCEPTABLE BY MAIN BOARD.
Cause: Game data (loaded from the GD-ROM to the DIMM board) are corrupted. The NAOMI 2 GD-ROM disk is used with the NAOMI main board.
Countermeasures: Make sure that the GD-ROM drive is firmly connected to the NAOMI board. Make sure that the GD-ROM disk is not scratched or contaminated. The NAOMI 2 GD-ROM disk software cannot run with the NAOMI main board. If you want to run the NAOMI 2 GD-ROM disk software, replace the NAOMI main board with the NAOMI 2 main board.

I'd lean towards what LV is hinting at with a power issue.
 
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TSXGuy

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So, I re-seated the DIMM board on the Naomi MB, and also unplugged the JAMMA loom from the Capcom I/O just in case that might be the issue. I'm running another CF card as we speak and I want to say it got through the menu quite a bit quicker after unplugging the Capcom I/O. Unfortunately, in my haste I did not use canned air to clean the DIMM but will try that if this doesn't work.

Now, if the above doesn't work and based on the way the Naomi is loading I fear another ERROR 21, I like Lemony's idea. I do have a Uni-SAN switching Power Supply available. It has knobs for + 5V and + 3.3V on the back and also has an on/off switch for 7 amps along with a red input for 115 (not sure what that is).

Anyway, is it safe to use this power supply on the Naomi? I just don't want to fry a board. Since, I haven't cleaned the CF card that I used AFTER the changes above, I'm going to deep format a new CF card and try and run one of the games that were causing me an ERROR 21 before I took the advice above.

Lemony, yes I am using the Blast power supply to give all of the power to the Naomi MB and for that matter the DIMM and everything else. Totally makes sense that I could have a power issue. Just waiting back from you, Mad and a few others on whether the power supply I listed above will work.

If I can get an answer tonight as to whether it's probably safe, then I'll plug it in and see if it fixes the issue.

Thanks again!
 
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madman

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Naomi boards can be picky about voltage. Have you measured the 5v under load?
 

Lemony Vengeance

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if you have a PC PSU with adjustable voltage, by all means, use that. Measure it before you add the Naomi to it and verify that it's at 5V and 3.3V, then add the Naomi and tune the voltage. if voltage is above 5.1v, itll fry your DIMM. Not even kidding.

the Naomi is a fickle bitch.
 

skate323k137

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if you have a PC PSU with adjustable voltage, by all means, use that. Measure it before you add the Naomi to it and verify that it's at 5V and 3.3V, then add the Naomi and tune the voltage. if voltage is above 5.1v, itll fry your DIMM. Not even kidding.

the Naomi is a fickle bitch.

5.1 is fine, as long as you're below 5.2 at the NAOMI itself. I actually run 5.15 at the connector on my NAOMIs, have done so for years. But yes, it is a picky beast, and if you go over 5.2 you can start frying stuff.
 

TSXGuy

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Lemony, Skate, Mad thanks. I'm really new to learning about power and the Naomi so I'll search for a few threads on that. I just don't have the slightest clue on how to measure. Here is the issue I have and I'll try and take a picture of the power supply. I am currently connecting the JAMMA loom with the 4 pin connector and the 3 pin connector that connect directly to the Naomi MB. When I looked at the connectors for said power supply, it has 2 connectors but they are both 3 pins. The guy I got it from says he's used it to power the Naomi but I don't see how? Do I only need to power the Naomi through the 3 prong plug? I would think I would need both just like the JAMMA loom.

I just realized in looking at it that it has a small green wire which has 3 pins. So, if you couple this wire with one of the 3 pins that would make 4 pins across just like the loom. Now to figure out where the ground wire goes because I'm figuring that's the reason for the extra 3 pin green wire.

Thanks
 
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madman

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There should be an 8-pin power cable connecting the Capcom IO to the NAOMI mobo, there should also be a 6-pin power cable connected from your PSU to the mobo. You shouldn't need anything beyond that. You would need to pick up a DMM, volt meter, multimeter whatever term you prefer to measure the voltage. If you're into arcade gaming it'll be a valuable tool. You should be able to pick up a cheapie for around $15 at Home Depot or similar place.
 

TSXGuy

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There should be an 8-pin power cable connecting the Capcom IO to the NAOMI mobo, there should also be a 6-pin power cable connected from your PSU to the mobo. You shouldn't need anything beyond that. You would need to pick up a DMM, volt meter, multimeter whatever term you prefer to measure the voltage. If you're into arcade gaming it'll be a valuable tool. You should be able to pick up a cheapie for around $15 at Home Depot or similar place.

Ahhh, I see where are going with this. I do have an 8 pin power cable that comes with the Capcom I/O. It connects to like the top part correct? I asked my engineer friend who is into this and he said I don't need that but now it makes sense. So to get this straight. Use one 6 pin connector only from the PSU to the 6 pin slot on the Naomi MB. Then use the 8 pin power cable connecting from the Capcom I/O and put that in the 8 pin slot on the Naomi MB. Then, leave the 6 pin and 8 pin connectors on the JAMMA loom unused correct?

If all of this is correct my only question is grounding.

Thanks Mad, makes a lot of sense. Hopefully when you reply back I'm getting your message clearly and not confusing things.
 

madman

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Someone with a Blast City can chime in on that, but what I said is how I have my setup hooked up. When using a NetDIMM you need the extra juice from the second connector, you can't reliably power it from the JAMMA edge/Capcom IO alone. If you were just using carts you wouldn't need that second power connection.
 
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