Neo Geo MVS-2 Help - Coin 2 only gives credit to Coin 1?

pincade

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Neo Geo MVS-2 Help - Coin 2 only gives credit to Coin 1?

Hi working on my first Neo Geo 2 slot and noticed an issue I was hoping you could help with:

***edited for clarity****

The issue is that no matter which coin chute I am putting coins in (player 1 or 2) it only credits player1 on the credit display.
So when I coin up, no matter how I do it, only the player 1 credit display gets the credit.

However Player 2 can hit start and 'steal' player 1 credits at any time. And it will correctly deduct from player one's credit display when doing so.

How do I allow a coin put into player 2's slot to register as Player 2 credit instead of always giving credit to player 1?

*******************


-The coin switches register properly on the hardware test. Each triggering individually when using the coin chute trigger.

-The Led displays also are working correctly as shown in the hardware test.

-I tried moving dip switch #2 to 'on' but it did nothing different.

-For some reason in soft dip settings for the cabinet coin 2 was set to 2 credits per coin (and would thus end up giving 2 credits to player 1 per coin) ; I changed that back to 1 credit per coin.

-I reseated the harness to the board, but that did not help.

-The coin switch wires seem to be separate of one another with coin 2 having a blue wire and coin 1 with a green wire.

Any ideas?
 
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Did you try going into the test menu to see what each credit slot does? Does 1 do 2, and 2 do 1? Is the cab even wired correctly? Is the coin counter hooked up to the MVS correctly (there should be two of them, one for each side). There's many things you need to check and tell us before we can move on.
 
In test menu the coin switches test correctly and independently - Coin 1 switch registers as Coin1 and Coin 2 with 2.

Cab does not seem to be hacked and wires to conenctors seem original, but never having a Neo Geo or Arcade before I am not 100%. Coming from the pinball world though it doesn't look like any hacks have been done though there is a question on wire color changes after connected to molex connectors (see below).

As far as coin counters, there is only 1 of them. Must there be 2 coin counters to register separate credits on player credits? The manual only shows 1 coin counter and there are no predrilled holes for a second counter on the coin control panel. I have not seen any pictures of 2 coin counters on the mvs .... is this the cause?

Here are some pics at what I am looking at:

Coin/test control panel:
Img_3192.jpg



Connections from coin counter to main harness:
Img_3199.jpg



Connections from coin switches to main harness. Here the wire color changes after being conencted to the connector. The blue wire (coin 2 switch) becomes green & black and the green wire (coin 1 switch) becomes yellow and black. I do not know if this is normal or not.

Img_3194.jpg



How does the above look and where else whould I check?
 
Hmm, perhaps I'm not understanding the issue, or am asking the wrong questions.

Are you saying, that when you coin up, the coin counter on the digital display is adding coins to just player 2? What I was suggesting is that those got swapped around (usually, depending on the Neo Geo, there are two coin counters. One for each side). I thought that was the issue, and when someone put the board back in, they hooked up the digital counters backward by accident.

Are you saying that, no matter what, coins are added to player 2 no matter which side you put them on? There should also be an option to share coin slots or have the separate in the mvs's option menu.

Sorry for not fully understanding the issue you are having. :(

EDIT: It's good that the game at least can acknowledge the difference between p1 and p2 coins. So you can stop searching there. It seems that there's something simple to fix your problem. :)
 
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No problem at all Rambo I am appreciating your help! :)

The issue is that no matter which coin chute I am putting coins in (player 1 or 2) it only credits player1 on the credit display. So when I coin up, no matter how I do it, only the player 1 credit display gets the credit.

However Player 2 can hit start and 'steal' player 1 credits at any time. And it will correctly deduct from player one's credit display when doing so.

I was hoping this is just a software setting but can't find the setting anywhere...
 
Okay, go to your hard dip switch setting menu. It should be the second one down. There's an on and off dip setting. I believe you can adjust this on the actual mobo. The setting should say 0 or 1, and each one will be either 1 coin slot or 2. So, you may have that dip set to 1, even though you have 2 on it? Give that a look and tell me what you see.
 
I checked that first...putting hard dip #2 to the 'on' position or 'off' position makes no difference...still just puts credits on player 1's side.

I thought it might be an actual hardware error on the mobo dipswitches, and that maybe it was stuck on 1 coin slot on dipswitch #2 no matter how I switched it...BUT it registers on and off for switch 2 in the test mode.
 
I'm not sure if this is going to make sense, but check the pinout on your edge connector, find where coin2 is and ground it out. If it coins up player1, then it would definitely be a board problem, if it coins player2, then you have a mix up in the wiring.
 
I will check the pin layout on the connector to the mb.

I have a diagram of which pin goes to which 'pin slot/number' in the manual so I should be able to do that accurately....but how do you 'ground it out'?
 
I will check the pin layout on the connector to the mb.

I have a diagram of which pin goes to which 'pin slot/number' in the manual so I should be able to do that accurately....but how do you 'ground it out'?
The last time I had to do it, I just took a small piece of wire and touched one end to ground, and the other end, touch it to the coin 2 pin for a split second.
 
It was the Motherboard all along!

I was able to do a mobo swap and the other mobo does not have this problem.

I noticed that with the bad mobo, by default soft dip setting for coin 2 is 2 credits per coin.

With the working mobo that setting default is 1 credit per coin.

I guess the question is now , what on the mobo would cause this or what would I need replaced on the mobo?

Who works on Neo Geo boards that I could send it into?

Thanks all for helping me troubleshoot this issue!
 
It was the Motherboard all along!

I was able to do a mobo swap and the other mobo does not have this problem.

I noticed that with the bad mobo, by default soft dip setting for coin 2 is 2 credits per coin.

With the working mobo that setting default is 1 credit per coin.

I guess the question is now , what on the mobo would cause this or what would I need replaced on the mobo?

Who works on Neo Geo boards that I could send it into?

Thanks all for helping me troubleshoot this issue!

Have you replaced the battery on this board? I don't really see how it could cause the problem, but if it involves the soft dips, it's not completely impossible that a battery on it's way out could be screwing things up.

Have you tried clearing backup ram? (Hard dip 1 I think.)

I also recommend uni-bios for it's superior debug capabilities.

I had game issues caused by a bad ram, some of the debugging I went through might be of interest, also you might want to post on the neo-geo.com forums.

(My log is at http://www.kohne.org/mike'sprojects/fixing-a-neo-geo-mvs-2-slot-board-backup-memory-error)
 
Have you replaced the battery on this board? I don't really see how it could cause the problem, but if it involves the soft dips, it's not completely impossible that a battery on it's way out could be screwing things up.

Have you tried clearing backup ram? (Hard dip 1 I think.)

I also recommend uni-bios for it's superior debug capabilities.

I had game issues caused by a bad ram, some of the debugging I went through might be of interest, also you might want to post on the neo-geo.com forums.

(My log is at http://www.kohne.org/mike'sprojects/fixing-a-neo-geo-mvs-2-slot-board-backup-memory-error)

Thanks I will look through your thread!

I have not changed the battery but that seems easy enough to try just have to go order one.

I did clear the backup ram but that did not do anything.

I might try unibios as I have heard about it but would have to order that too.

My account weas never activated at the neo geo forums since last year! So I can't post... do you know a mod there that could help?

Thanks!
 
I'd send it to channelmaniac to get repaired. However if you want to get frisky and try to fix it yourself, if you trace back from the edge connector where coin 1 and coin 2 connect, you're probably going to see those lines going to some resistors, and some caps, and then a chip of some kind. That chip is probably your problem. Once you go past that chip the signals aren't really independent anymore, so you're likely looking at something really close to the edge connector. 10% chance though that it's something more complicated, Channelmaniac could fix it either way but may not want to if you hack up the board, lol.
 
Wait: now that I think about it, your issue is probably much more complicated than that since it works fine in test mode. I'd definately send it to channelmaniac.
 
Does anyone have channelmaniac's email they could pm me?

I have tryed to signup on the neo geo forums but I never got an activation via email and that was a year ago. I can't post anywhere on the site either... Never made any enemies there either as I never got to post lol! (not that I don't like this forum because I do, thanks for all the help btw that I am receiving! )

So if anyone knows an admin there that can help please shoot me a pm.


The good thing about all this is while looking at the battery I did notice the 'fuzz' start to build so I ordered some lithium round battery holders from Jamma Nation X (please tell me their store is still active as I just placed an order yesterday and paid for it already!). I probably would never have noticed the fuzz without trying to troubleshoot this problem and with the advice of mhkohne.
 
You can get in touch with channelmaniac here on this forum, or visit his site at

http://www.arcadecomponents.com/index.html

Thank you much appreciated, that's just what I needed!

I had stumbled onto that site before just looking for neo geo parts in general, glad to know the owner is KLOV member and a neo geo guru as well!

Thanks for that link will contact him!
 
It's a BIOS issue.

Replace the BIOS chip.

I've been on business travel again then out sick from Fri night through Monday... so I'm a few days behind on everything again.

Raymond
 
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