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Apocalypse

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It doesn't XDThe "good" board (HA..good), had perfect condition, no rust or leak, new rams from serious supplier like Digikey (so no fake chinese shit at least), new caps, new reset ic, and guess what? the same. It doesn't work.
Doesn't work like what? What do the LEDs do?
If you haven't identified the faulty component then it can be a long path.
 

XtraSmiley

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We're (almost) in business! Found an other rotten trace and now red and green are back:





If anyone has a good scan of the manual, looks like the component values are listed.
So far I only replaced C61.But that didn't change anything regarding the maxed out sound. Whatever its position I don't see any change in the measured resistance between pins of VR2. Maybe it's cooked. @ekorz :whistling: ?
Wow, I KNEW you would get it working, I just didn't know it would be THIS quick!

Amazing as always.

Now, NOBODY sell this man the Crystal System multi, UNTIL he finishes up the multis he's working on. I don't want him distracted! :P
 

Derick2k

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Ok, found a link on NG of someone that has/had the manual. I dont have creds there so maybe someone here that does can ask for scans??

http://www.neo-geo.com/forums/showt...-Manual-Info&p=3994851&viewfull=1#post3994851

Also, anyone care to repro the move strip for CoK, found this pic floating abouts

1588536705-2075287222.png
 

Apocalypse

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Q2: A1266Y Transitor
Q3: C3198Y Transistor
Ordered.
It is a stereo b103 pot and thankfully matches the footprint of a Gameboy Advance volume pot perfectly, you just have to bend the pins to fit through-hole instead of surface mount. New pot on the right, above, works great.
And ordered!
 

TheDeath

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It doesn't XDThe "good" board (HA..good), had perfect condition, no rust or leak, new rams from serious supplier like Digikey (so no fake chinese shit at least), new caps, new reset ic, and guess what? the same. It doesn't work.
Doesn't work like what? What do the LEDs do?If you haven't identified the faulty component then it can be a long path.
unfortunatly no.. don't remember the exact spot but first one lights up, then off, second one lights up, then off, both lights up, then off. Keeps repeating that in loop
 

Apocalypse

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unfortunatly no.. don't remember the exact spot but first one lights up, then off, second one lights up, then off, both lights up, then off. Keeps repeating that in loop
Then probably faulty SDRAM, one or both closest to the JAMMA connector. Or severed traces between those chips and the VRenderZero.
 

TheDeath

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unfortunatly no.. don't remember the exact spot but first one lights up, then off, second one lights up, then off, both lights up, then off. Keeps repeating that in loop
Then probably faulty SDRAM, one or both closest to the JAMMA connector. Or severed traces between those chips and the VRenderZero.
That's exactly what i changed, all 3 of them with brand new parts, i had the same problem before and after. There's no leakage, at all, nowhere. I just think that the Vzero is coocked somehow, find a replace for it is almost impossible
 

Derick2k

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unfortunatly no.. don't remember the exact spot but first one lights up, then off, second one lights up, then off, both lights up, then off. Keeps repeating that in loop
Then probably faulty SDRAM, one or both closest to the JAMMA connector. Or severed traces between those chips and the VRenderZero.
That's exactly what i changed, all 3 of them with brand new parts, i had the same problem before and after. There's no leakage, at all, nowhere. I just think that the Vzero is coocked somehow, find a replace for it is almost impossible
Gotta try to find a donor from the companies that made these, I think a few consumer products might have carried it on dl. Some type of Mpeg player, etc.. I'll try to dig something up on it if I can. Doesnt the story goes that MagicEyes Digital in partnership with ADC Chips created the vrenderzero for Brezzasoft? Being SOC, uses a cpu from ADC Chips and some audio processor. I know there are vrenderzero+ chips available, but those dont work I guess.

Anywho, hope you get it fixed.
 

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Apocalypse

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That's exactly what i changed, all 3 of them with brand new parts, i had the same problem before and after. There's no leakage, at all, nowhere. I just think that the Vzero is coocked somehow, find a replace for it is almost impossible
Maintain service + test before powering the board up, power the board and hold for a couple of seconds before releasing. See if the test menu appears.
 

ack

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That's exactly what i changed, all 3 of them with brand new parts, i had the same problem before and after. There's no leakage, at all, nowhere. I just think that the Vzero is coocked somehow, find a replace for it is almost impossible
Maintain service + test before powering the board up, power the board and hold for a couple of seconds before releasing. See if the test menu appears.
Will this work without a cart installed?
 

TheDeath

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@Apocalypse i just tryed the test+service few minutes ago since i didn't saw your reply and i magically got the menu 8|
I thought this crap was busted.
The 32kb Sram was giving me INVALID, then i hit FILL SRAM and now is valid at all boot.
The happy music is present, also i'm able to screen test, all colors present.
Hovewer the game is still not booting.. could it be just that at this point??
 
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ack

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I would plug in a game and go into the self-test menu again. If it still says "FAT no found" it would be an indication there is an issue reading the from cart.
 

TheDeath

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I would plug in a game and go into the self-test menu again. If it still says "FAT no found" it would be an indication there is an issue reading the from cart.
Thanks, i forgot to mention that i do have some information when i plug the cart, i'll post a picture tomorrow.
I noticed that the sram was sometime invalid, i pulled it off and programmer gave me a bad bus test. I have changed it with another 62256 70NS and made it valid again on the test menu but unfortunatly that didn't change.
I'm afraid my dc buck converter is too low on the 3V (wich is 3V exact, maybe it's too low, should it be 3.3V/3.4?).
When i reset the board with the button it just goes all black. DS1 and DS2 lights up once togheter than went off all the time. From what i've read this stands for the regular booting sequence, but unfortunatly it doesn't for me. I'm a bit confused on what really goes on in this
 

TheDeath

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Yeeeeessss..... holy cow this took me forever to fix... the funny part is that i'm not even sure what did the trick X-D
I just realized that the board was giving me a very random cart check in the test, sometimes the cart was found, sometimes was not... and even the sram fill was very random.
First i changed the 62256 next to the bios, my programmer tested it as good but i've changed it anyway.
Then i went to check the hc245 buffers near the resistor arrays, they basically make a bridge from the cart to sram/Vrender. They were all tested good, however when i tryed again after put them back in the motherboard the game started to boot all the time but it was soft-locking after the character selection screen.
There was no rust near them or underneath (the board is in superb conditions) so i was suprised on what the hell actually happened doing so.
When i started to work on this board months ago i changed the 3.3v regulator, using a buck DC-DC converter (the original LM was rusted all the way), but after checking carefully my power i realized that the output voltage was 3.05/3.1 and it was probably not enought.
I then tryed with a small solution, just to save some time, and i used an AMS117 3.3 in sop. Game started to working better, however it did not past 10/15minutes of working and it keept freeze again. Was probably not good for the board amperage and i did not keeped attention to the datasheet.
Then i just bought an LM317 with ADJ, arrived today, and used 220R and 390R to obtain 3.4V and nearish 1.5Amp. After that, it worked straight for an hour, i turned it off and consider it as work done.
 

djsheep

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@brizzo any word on Dongul or other games being playable on the multi ;)
 

mackenzie

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hello

Hello everyone Does anyone know where I can find the GAL to download the game cristal of the kings?
 

mackenzie

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is there any universal gal to download? I have a board with the burnt gal! need to replace to try to fix a card
 
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