Reminder: Check your Varta batteries

[brentsg]

I don't understand your second question, its not like you need to avoid PCBs that have batteries, just need to keep an eye on them. The ones of most concern are the suicide PCBs like any CPS2 (and CPS1?), and DOJ Black Label.

Is DOJ Black Label the only suicide battery Cave PCB?

[Dave_K.]

Is DOJ Black Label the only suicide battery Cave PCB?

DOJ Black Label and Progear (CPS2)

[robivy64]

Solved.

[MKL]

What you did works but is methodologically incorrect. The correct way to do it is to remove the 470ohm resistor and leave both diodes on so that when the board is powered the RAM is supplied with +5v (as happens before the mod), whereas on your board the RAM is now always supplied with the 3v from the battery. The only reason it works is because the RAM ICs used on this Cave PCB have a wider operating voltage range. If you did the same on an MVS board (which have an identical charging circuit) it wouldn't work because the standard 62256 ICs only work within a 4.5-5.5V range.

[cools]

I believe the resistor has been removed too, it was stated when posted over on AO.

[MKL]

Once the 5v diode is removed it is pointless to also remove the resistor as it makes no difference.

[sourdiesel]

also another tip for ketsui owners ... if you dont have the updated rom and you remove the battery and dont put a new battery in, it will crash ... i got the updated rom and solved the problem ... dont have a battery in my ketsui coz i play defaults and i lost a DOJ pcb due to a leaky battery aswell

[Dave_K.]

also another tip for ketsui owners ... if you dont have the updated rom and you remove the battery and dont put a new battery in, it will crash ...

[removed wrong assumption that this was the same as the freeplay bug]

[sourdiesel]

well ... it crashed for me even while set to defaults ... at least with my board it did ... was not set to free play at all

i could start the game as long as i did before it cycled into demo mode as soon as it did it crashed, and was not on freeplay

[Dave_K.]

well ... it crashed for me even while set to defaults ... at least with my board it did ... was not set to free play at all

i could start the game as long as i did before it cycled into demo mode as soon as it did it crashed, and was not on freeplay

You were right about this! I removed the battery in my Ketsui a few weeks ago, and was playing fine, then all of a sudden yesterday it crashed during the demo sequence. I investigated further and determined why its happening and how to prevent it (without having to install a battery or upgrade the rom).

[PC Engine Fan X!]

Fascinating insights into why a Ketsui PCB with battery removed still crashes. Even the plain-vanilla flavored DDP-DOJ PCB has a slight audio bug which I discovered and it was with your confirmation that it was a bonafide bug that Cave did not bother to fix anyways before releasing it to game centers worldwide.

PC Engine Fan X! ^_~

[RetroRepair]

Quick question, if I have accidentally flipped the switch on a DOJ (not BL) PCB will it kill the PCB? I know it does on the BL versions, if it does, can it be fixed? I ask since after changing my battery I get nothing on the screen at all. I also think I did flip the switch with my palm

[RetroRepair]

"RESOURCE ERROR: MEMORY NODE USE"

I get this in the test menu, guess I'm screwed

[DasFool]

Tonight I successfully removed the varta battery on my PGM motherboard, Ketsui, and ESPGaluda, and replaced it with a CR2032 socket and battery. The socket fit perfectly on the PGM motherboard (components side), but there's no way it would fit on the components side of Ketsui and ESPGaluda so I soldered it onto the solder side. I completed this mod by first removing the original battery, then the 470 ohm resistor marked "R11." According to the schematic in this thread, that's all that should need to be done.

[kernow]

"RESOURCE ERROR: MEMORY NODE USE"

I get this in the test menu, guess I'm screwed

ho noes

let me know if you manage to fix it, actually don't because I sold mine and I'll be gutted.

[jonny5]

well ... it crashed for me even while set to defaults ... at least with my board it did ... was not set to free play at all

i could start the game as long as i did before it cycled into demo mode as soon as it did it crashed, and was not on freeplay

You were right about this! I removed the battery in my Ketsui a few weeks ago, and was playing fine, then all of a sudden yesterday it crashed during the demo sequence. I investigated further and determined why its happening and how to prevent it (without having to install a battery or upgrade the rom).

mine did this....and it had a battery?

weird

[rtw]

You were right about this! I removed the battery in my Ketsui a few weeks ago, and was playing fine, then all of a sudden yesterday it crashed during the demo sequence. I investigated further and determined why its happening and how to prevent it (without having to install a battery or upgrade the rom).

I read your post at AF but how can the board retain a corrupted state when there is no battery to power the NVRAM ?

[Dave_K.]

Quick question, if I have accidentally flipped the switch on a DOJ (not BL) PCB will it kill the PCB? I know it does on the BL versions, if it does, can it be fixed? I ask since after changing my battery I get nothing on the screen at all. I also think I did flip the switch with my palm

"RESOURCE ERROR: MEMORY NODE USE"

I get this in the test menu, guess I'm screwed

Did you resolve this? Did you replace with a similar or different battery? Have you tried just removing the battery to see if it works? I've been running my DOJ without battery for months and everything is fine, although it powers up with defaults...which is not a problem for me since I don't use free play.

I read your post at AF but how can the board retain a corrupted state when there is no battery to power the NVRAM ?

I could be wrong, but the conditions and steps I explained lead me to believe this is whats happening. Isn't NVRAM by definition non-volatile?

[rtw]

I could be wrong, but the conditions and steps I explained lead me to believe this is whats happening. Isn't NVRAM by definition non-volatile?

Not necessarily, it can be FLASH or battery backed RAM. The NVRAM on the PGM is battery backed.

If you look at this circuit you see the battery powering RAM.

[sourdiesel]

well ... it crashed for me even while set to defaults ... at least with my board it did ... was not set to free play at all

i could start the game as long as i did before it cycled into demo mode as soon as it did it crashed, and was not on freeplay

You were right about this! I removed the battery in my Ketsui a few weeks ago, and was playing fine, then all of a sudden yesterday it crashed during the demo sequence. I investigated further and determined why its happening and how to prevent it (without having to install a battery or upgrade the rom).

nice -- i knew i was on to something .. read your article and gonna switch back to the original rom , i never noticed the different lockon sound. thanks again!

[rtw]

Anyone know where I can buy these batteries in Europe ?

[spadgy]

I'd asked some questions about this on AO, but I thought I'd check here.

On AO, Rob recommended neutralising a leaking DOJ Varta's acid with baking soda (an alkaline to counter the acid).

However, I read elsewhere that the Varta will link alkaline if it is an NiMH battery. I checked my removed Varta battery, and it is indeed an NiMH battery. It seems that its a common misconception to call anything that comes out of a battery 'acid', when some times it is quite the opposite.

So should we be neutralising with an acid?

And then Ed mentions mixing baking soda and vinegar, which is mixing an alkaline and acid together. Doesn't mean you'd end up with a neutral solution? Is that the point - that you clean it with a neutral mix?

I removed my battery and cleaned it with Baking Soda, assuming that it was an acid leak. Now I'm worried any Baking Soda residue (I cleaned off all that I could, but there must be some in the nooks and crannies) will cause damage as a corrosive alkaline.

Please help! I'm confused and worried!

[Dave_K.]

To be honest, I used both, baking soda and white vinegar, not really knowing the chemistry of which was best to work with that battery. Granted I didn't use a lot of either, just rubbed a small amount of baking soda on the effected area, then a q-tip dipped in white vinegar to clear the baking soda off, and surrounding areas, until it was nice and shinny. I didn't "mix" the two, so I think the vinegar afterwards probably neutralized any remaining alkaline appropriately. I also used a small wire brush to clean under the resistor pack, and around any metal parts I couldn't get to with the swab. Again, see pics at the top of this thread for how it turned out. A year and a half later, and my board is still working fine, no further corrosion.

So I think you'll be fine Spadgy, if you use the canned air to blow out any remaining baking soda, and then swab the surrounding battery area with vinegar.

[spadgy]

Exactly (pretty much) the plan I was formulating, so it's good to see that it's worked OK for you Dave.

I already did:

Remove battery
Clean with baking soda
Clean with water
Dry
Tested and works 100%

So next I'll do:

Air dust clean
Vinegar clean
Water clean
Dry
Play!

[Coryoon]

Sorry for the old bump (well actually I'm not) .

I have a Ketsui PCB (had it for quite a while now), and I kept meaning to find out some inf about the battery, so I did a bit of searching and ended up here.

My Battery seems clean-ish, although their appeared to be some tiny clear drops on the base of the battery (almost like moisture) - which wiped off.

http://i62.photobucket.com/albums/h90/C ... to-174.jpg
http://i62.photobucket.com/albums/h90/C ... to-176.jpg

The battery appears to have a little 'dink' on it, but it seems ok.

http://i62.photobucket.com/albums/h90/C ... to-175.jpg

The underside of the PCB did show some blistering, and I'm guessing that these are from a previous soldering effort (perhaps the battery was replaced?)

http://i62.photobucket.com/albums/h90/C ... to-177.jpg

---------

I appreciate any comments on the above.

Moving forward, I guess for the future it wouldn't be a bad idea to just remove the battery.

From what I have seen on this thread so far I guess I can just rip the thing off the board and live happily ever after??

> I note that I will get the crash screen if I don't enter a credit fast enough, but I seem to get that at the moment anyway.

If it's only that I have to worry about, then it's fine - I can just turn it off and on again and remember to hit the credit button in time?

Its not the case that If I get the error screen the board is totally dead??

It's easy to get paranoid about this, because the board wasn't that cheap, so please humour this old queen a bit and put my worries to rest.

[Dave_K.]

Honestly that battery doesn't look bad, but if you are seeing it leak acid, then you should desolder it and remove from the PCB. As you stated, you just need to enter a credit before the demo starts and you should be fine. If you forget to do this and the board crashes, its not permanent, just restart it and put the credit in before the demo.

[Coryoon]

Thanks Dave,

Yes, whilst the battery seems fine, I removed it, just so I don't ever have to worry about it ever again.

http://i62.photobucket.com/albums/h90/C ... to-178.jpg

Out of interest, is there any point in keeping those CR2450 batteries in the likes of Mushi and Ibara?

Thanks again.

[rtw]

I note that I will get the crash screen if I don't enter a credit fast enough, but I seem to get that at the moment anyway.

Sounds like you have the first program version, you should get it updated.

http://www.world-of-arcades.net/Cave/Ke ... isions.htm

[Coryoon]

I note that I will get the crash screen if I don't enter a credit fast enough, but I seem to get that at the moment anyway.

Sounds like you have the first program version, you should get it updated.

http://www.world-of-arcades.net/Cave/Ke ... isions.htm

That would be cool, and in theory made a little easier because the chip is socketed ...

... but I have no set up to burn a new chip.

Where could I get a chip that has been pre-loaded with the fixed file?

[emphatic]

Where could I get a chip that has been pre-loaded with the fixed file?

http://hobbyroms.com/