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I'm talking about the chips not the presets

EDIT: Not working on my side
 
I'm talking about the chips not the presets

EDIT: Not working on my side
CMOS or not makes no difference on my side, they can all be burnt without any issue and regardless of the programming voltage needed (didn't experience more issues with 21V devices compared to 12.5V ones).

P.S.: Sorry it didn't work for you. Was the chip fully erased (full of 0xFFs)?

P.P.S: Not sure it has an impact but I'm using Win7 Pro SP1 32bit.
 
sounds like maybe a hardware fault.

cmos chips use 12.5v
nmos chips use 21v or even 25v

upto 27512 is 28pin, over that is 32pin and has the power on different pins.
so maybe there are pin driver problems.
it could be worth checking VDD(pin28/32) and VPP with a meter while trying to program a chip.
 
and DO NOT power it from the usb cable - specially if it's from a laptop.
 
@Trol thanks for the pictures, looks identical to the one I've got.

@archimage Topall Ver8.25 (2015-07-31)

Can you guys please do a test for me? Go in "Cofig" tab and change parameter "delay" to 1ms and try burning a 27C128/27C256/27C512 again.
Works for me, thanks Apocalypse 8o
 
@stj so I guess if I make an adapter I could revert from whatever where the power pin is on pin 32 to pin 28 ? that's what you're suggesting after testing the pins ?
 
had success writing the 27128 chip thanks @Apocalypse with 27128 21v preset and 1ms.

however I have only 27256 12v preset for which doesn't work for both the 256, is there any trick to force the voltage to 21 ?

EDIT : Eprom eraser just died from stress, I guess those chips are cursed
 
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get the datasheets for the eproms and you will know the VPP voltage required.
and i'm pretty sure no nmos (non c variant) used 12.5v
so your programmer has a shit parts database!
 
Got a pretty clean original GnG PCB, but it's booting to this screen (random colours), I can faintly make out some text down the bottom of the screen. The PCB stack has some sag, but the previous owner had it working on his cab prior to selling it.

Anyone seen this before, or got any hints where to start looking? I've triple checked and beeped out the pinout of the adapter I built, I didn't populate 2P controls though but I assume that shouldn't cause this issue.

gng-2.JPG


gng-1.JPG


Thanks in advance.
 
It just boots to that or you can hear the attract sounds like its kind of playing blind? I had to have a PROM burned located at 2E on my board but that only made the background and some of the sprites disappear.

Otherwise, I think all the graphics are on the bottom board so maybe worth spraying down the IDE connectors with some Deoxit just to eliminate that. I think you can actually boot the game without the bottom PCB as well just to see if you still have same issue. If so your issue is on the top board then.
 
No sounds, no activity on the amp or movement. Looks like it’s crashing on boot?
 
Program ROMs are the ones next to the cpu on the top board. Maybe check them with mame and basic cpu checks then if it just crashing.
Dumped all the ROMs, they all read fine except for 01, which I reburnt with no real change (except the faint text down the bottom of the screen doesn't seem to appear anymore).

Have also tried with the bottom board unplugged, but the only difference that makes is the colour isn't white or purple (but blue?).

I'm new to diagnostics, but have a logic probe and multimeter, is there any basic tests you can recommend I can try? I gotta start learning the basics.
 
Also, FWIW, I had no issues burning the 27128 chip with my Top3000 programmer using the built in Toshiba profile.
 
So one of the program ROMs was bad, eh? That sucks it didn't fix it. I'm also no expert but if the board won't boot you still seem to have an issue CPU related.

I'd check the voltages on those roms and the cpu. Good sanity check as well of the JAMMA adapter you made. If that is good start probing the CPU (clock, reset, address, data).

I also know these GnG boards can be plagued with Fujitsu chips which are known to fail. If you see some of those polluting the CPU circuitry maybe give them a closer look too.
 
Thanks for the advice @LittleLarrySellers, I'm going to shelve the board for a bit and hunt down a Capcom adapter to rule that out (I'm pretty sure my adapter is fine, but you never know).

I'll report back after I do those diagnostics you suggested too. Did have high hopes when the first chip didn't match in Romident.
 
I got mine from the man himself -> https://voultar.com/index.php?route=product/product&path=70&product_id=75

Good luck. Hopefully its not the CPU. GnG one is frigging soldered in. I know this because I recently upgraded to the HighScoreSaves kit and I had to desolder the beast to get the kit installed. But now I have my high scores for when I never beat this game saved!
 
Judging by the age of this game, I’m assuming desoldering the CPU was troublesome due to the old solder?
 
I've gotten MUCH better at desoldering. I can't tell you how many times I royally fucked up. I actually had the HighScoreKit for like 6 months sitting in a box before I even tried this. No way I was gonna touch my GnG board until I was really confident.

I did the fresh solder routine and was careful and got the CPU out with no issues really. The trick is I got a better feel for how to do the troublesome pins that don't come clean on first attempt.
 
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