TMNT 89, bad RAM or ROM?

[Mad Mage]

This seems like a question any arcade expert would easily know the answer to.

I have a TMNT board (the first game) that's always worked great. I just popped it in my cabinet and it's failing the RAM/ROM check. The last item on it's list is labeled as "Bad".

K15
3C2D

What ever shall I do? I don't know anything about fixing boards. How can I tell if K15 is RAM or ROM? Is there a good way to locate it on the board? And of course, the real question is, can I locate a replacement chip?

I have chips for the 2P and 4P versions of the game (2P are in now). I haven't tried swapping the chips because I don't think those are the bad chips, and I don't want to risk further injuring the ancient board anymore than I have to.

Thanks

 

[channelmaniac]

K15 is one of the program ROMs.

Swap the 4p program ROMs into it and see if it's working.

Look next to the sockets on the PC board and you'll see tiny writing that identifies which chip is which. One will be labeled K15.

I can burn you a replacement ROM if you can tell me for sure which revision it is. Otherwise, send me the 4 program ROMs and I'll match 'em up and burn the correct replacement for you. It's a service I offer through my website.

Keep in mind it could be as simple as a bent pin on the K15 ROM. Check all the pins as you remove the 2P ROMs.

RJ

 

[Mad Mage]

You were right, thanks. Contacting you via PM about the chip.

 

[SetaSouji??]

Is this TMNT itself or just a TMNT board in general? If it's the latter, what game?

 

[Mad Mage]

It's actual TMNT (89).

I've PMed the kind channelmaniac about getting a replacement chip. I'd further fiddle with my chip and try to make it connect to the board better, but I'm more worried I'd break something else in the process. It seems more likely to me that the chip simply went bad (I've taken it out and put it back in twice now).

 

[Artemio]

Might not be the case, but worth testing.

On my Sunset Riders board (the same basic hw) the last item was reported as BAD, it was an EEPROM if I recall correctly. I read somewhere in the MAME documentation that you needed to boot the board with the test button pressed to reset all EEPROM values to factory defaults oon case they were corrupted. It worked for my PCB.

 

[Mad Mage]

Sounds like somthing I should try. But does a TMNT board even have a test button? I thought it was so old, it only has DIP settings, but no test button?

 

[channelmaniac]

Look on the PC board for a tiny square switch. It's typically next to the P3/P4 connectors.

 

[Mad Mage]

Okay, I've spent a long time trying to locate this switch and I don't think my board has one. I can find the P3/P4 connectors as wel as the dip switches, but I can't find any other button or switch.

I've now looked at pictures of similar konami boards and know what the switch is supposed to look like as well. In doing so, other websites also suggest doing this "ram reset" every time the 2P/4P chips are switched, so I would like to try it, but I have to wonder if it's done differently on this board?

I did try setting the dip to test mode and booting it up, but that didn't help.

 

[channelmaniac]

Please post a hi-res pic of the board.

 

[Mad Mage]

K, whole board:


http://home.comcast.net/~magemail/tmnt%20board1.JPG

Corner where test switch usually is:

http://home.comcast.net/~magemail/tmnt%20board%202.JPG

Thanks again, guys.

 

[Opethian]

http://www.mamext.net/manuali/tmnt.pdf

 

[Mad Mage]

Yes, I've seen that. It's what I used to figure out the dip settings. But other than the dip settings, it seems full of a bunch of circuitry info which is beyond me. If the location of a test button is in there, I did not see it.

 

[Artemio]

Did you try using the test button of your cabinet/super gun while booting? I used the little square button in my Sunset Riders one, again it might not be the same problem or solution.. but it is a very easy one to test and discard.

 

[Mad Mage]

That is what I would like to try. After you suggested doing so in your other post, I researched old Konami PCBs online, and indeed, other people and websites suggest trying this as well.

I've posted a pic of my board, but I don't think it has a test switch. My cabinet does not have one (or at least one I know of), as it is a generic jamma setup.

Assuming I can't find a test switch, I'll send channelmaniac some money and he'll burn me the apropriate chip. But I could save him some time and me a little money if your suggestion solves the problem.

 

[Artemio]

JAMMA includes a Test Button]/siwtch in their standard:

http://www.jammaboards.com/jcenter_jamma_pinout.html

It is pin 15 and is used by most JAMMA games to enter settings, of course there are some JAMAM boards that are only configured via DIP Switches anyway. If you don't have a button you can check if pin 15 on your JAMMA harness is wired or you can short it to ground in order to use it.