New! Dark mode!

Browsing Pinside at night? Getting tired of all the white? Switch to dark mode using the button in the top right (or CTRL-B)!

(Topic ID: 86803)

Sega Batman Forever: DMD garbled and not working properly


By FreeBee

6 years ago



Topic Stats

  • 21 posts
  • 8 Pinsiders participating
  • Latest reply 6 years ago by FreeBee
  • Topic is favorited by 3 Pinsiders

You

Linked Games

Topic Gallery

There have been 6 images uploaded to this topic. (View topic image gallery).

image.jpg
2014-04-11 20.37.12.jpg
2014-04-08 12.11.43.jpg
2014-04-08 12.14.51.jpg
2014-04-08 12.09.21.jpg
IMG_2241[1].JPG

#1 6 years ago

Hello pinside, I need your help once more.

Last weekend we went and bought a working batman forever. It was in very nice condition, nice playfield, everything working, snappy flippers. About everything you need when buying a pinball machine.

However, today luck changed. A colleague turned the machine on, and instead of the normal display, it showed up all garbled like in the attached picture.

It was not blanking out or resetting or had any problems whatsoever before today, so something must have failed. I've tried reseating all connectors and ribbon cables without luck. What could it be?

IMG_2241[1].JPG
#3 6 years ago

Just a wild guess, but driver board perhaps? Since the DMD is getting power, and no lines are out and it displays, it would lead me to believe it's something to do with bad signal being sent from the board.

#4 6 years ago

There's a service bulletin for Sega DMDs...there was a new connector that was recommended - I think some of the parts stores sell it.

#5 6 years ago

pinball life sells it, i just bought one from them. My display worked fine but i did it as a pre-cautionary. I wouldn't thing that would have to do with it though, as that serice bulletin is more for dmd getting bad power rather then displaying bad information. If you search around google you can find the instructions to the service bulletin, it describes in it what it fixes.

#6 6 years ago

Power issue service bulletin:
http://www.sternpinball.com/downloads/sb106.pdf

Also, if you did a ROM update, have to make sure you use 120ns or faster EPROMs:
http://www.sternpinball.com/downloads/sb65.pdf

Also make sure your display ROM major version matches your CPU ROM version:
http://sternpinball.com/downloads/sb150.pdf

Is the game playable? Is the only thing bad the display? If so, that looks like a bad display RAM to me.

viperrwk

#7 6 years ago

Alright, there's a few tips I can work with. I'm going to check tomorrow.

No, we did no ROM update ourselves, we have it barely over 2 days. There are stickers on the chips of the displays, so it might be ROMs that are not original, though it was working until today.

The game is playable, only the display is gibberish. The guy it was previously from just sent a mail, and he said it might have something to do with the square IC on the back of the display. It's probably not making good contact. Broken foot, thus not making contact somewhere perhaps. If that would be the case it would rule out the power problems, since the display is on, and not blanking/resetting. It still is a good idea to renew the connector and/or cabling though.

#8 6 years ago

Well, I did some measurements just now:

4,88V at the connector on the DMD.
4,92V at the connector of the 5V supply.

I've also noted some blanking now regularly, that would mean that the garbled image blanks out for a fraction of a sec and comes back up again. It kind of contradicts what I stated yesterday, that I did not see blanking, but now I do.

How can a working display degrade so fast?

#9 6 years ago
Quoted from FreeBee:

How can a working display degrade so fast?

Connectors.

If you have a broken pin on one of the ROMs, it could cause your display to blank out or other strange behavior as well. Verifying the ROMs for both contents and integrity of the pins as well as correct speed is an easy first step. And getting the power kit to install a good second.

viperrwk

#10 6 years ago

yeah i would get the new power connector kit, as it specifys that is is supposed to fix exactly what is going on with your voltages. In it, it says those dmds are very very picky with their voltages and even the slightest drop down from 5v can cause issues, hopefully its that easy and that fixes it.

#11 6 years ago
Quoted from FreeBee:

Well, I did some measurements just now:
4,88V at the connector on the DMD.4,92V at the connector of the 5V supply.
I've also noted some blanking now regularly, that would mean that the garbled image blanks out for a fraction of a sec and comes back up again. It kind of contradicts what I stated yesterday, that I did not see blanking, but now I do.
How can a working display degrade so fast?

Do you get the Batman and version number? Or is it always scrambled? Blanking out is a low 5v issues (resets start at as low as 4.85vdc!) but it doesnt scramble, just resets constantly....

i am going to agree with viper and say a RAM issue. These PCB for the large display is probably insanely difficult to work on, hopfully the ram is in a socket, and can be reached with out pulling the display glass. If so, i would try that as a non invasive fix.

#12 6 years ago
Quoted from viperrwk:

Power issue service bulletin:
http://www.sternpinball.com/downloads/sb106.pdf
Also, if you did a ROM update, have to make sure you use 120ns or faster EPROMs:
http://www.sternpinball.com/downloads/sb65.pdf
Also make sure your display ROM major version matches your CPU ROM version:
http://sternpinball.com/downloads/sb150.pdf
Is the game playable? Is the only thing bad the display? If so, that looks like a bad display RAM to me.
viperrwk

And these service bulletins are all gone now thanks to Stern's newly redesigned web site...

viperrwk

#13 6 years ago

I get the feeling I'm dealing with both problems and we are just severely unlucky. (though, the pin is sweet looking)

The game was fine the one moment, then it was turned on and the display was scrambled.

These are the chips on the board of the display. They look 'custom', we did not put them in there. I might have to pull off the sticker to see the correct type, but I'm sure the correct ones are used, otherwise the display wouldn't have worked before. We might need to get other ones just to check.
2014-04-08 12.14.51.jpg

Today I also noted the display blanking out quickly, then restarting. Here's me measuring the connector.
2014-04-08 12.09.21.jpg

And yes, I noticed the links weren't working anymore, I was about to get to that but you were ahead of me.

#14 6 years ago

The ROMs look like they were reprogrammed and they are of the correct type for that board. The -12 indicates they are 120ns ROMs. Unless you have the ability to easily check them or replace them I would assume they are ok as the pins and sockets look ok to me (from what I can see.)

Your voltage is low. Definitely need the voltage kit. Marco used to have stock but is currently out.

If that doesn't fix it I'd go with the RAM.

viperrwk

#15 6 years ago
#16 6 years ago

Make your own. Two pieces 18 gauge wire. Five foot length. Solder and shrink wrap in a loop. Reuse plug on your display and install per update. Will save some time and money.

#17 6 years ago

ya especially since he is in the Netherlands, pretty sure there has to be somewhere closer to him with molex connectors

#18 6 years ago

The connector/wires are not a problem. But I don't think it would help much, as the voltage is only marginally higher when measured directly from the 5V power supply, and that is only 4,92V as stated before. My guess is that PSU components also need an upgrade (new capacitor / bridge rectifier), next to some juicier wires to the display.

Also, which chips would be the RAM?

2014-04-08 12.11.43.jpg
#19 6 years ago

How much ripple do you have on the circuit? Might be time to replace those four 4700uF filter caps. Maybe you get a few tenths of a volt more out of it.

.1v is an acceptable voltage drop across that connector, but 4.8v is borderline for the display. It will proably start resetting. For good measure i would still redo with trifurcon. Get rid of the loop style idc on the power board too. There is extra connector pin spots to individually crimp them on the power board from what i remember.

#20 6 years ago

Well, I'm not sure about any ripple on the circuit, but my guess is that it's definitely a good idea to at least put in a fresh bridge rectifier and caps in the 5V circuit. Plus new cabling and connectors to the display.

I have the display at home now, as tomorrow we go visit the seller to pickup another pinball. He also has another batman and we can verify whether it is the power supply. I've noticed something else when measuring and checking some stuff on the DMD board.

2014-04-11 20.37.12.jpg

This is the power board directly under the DMD driver board. The diode (D7) in the middle measures conductivity in both ways. I've checked it with some other diodes elsewhere on the board, but they appear to be good. What's strange is the diode seems to be connected with the transformer for the high voltage (?). I'm not too sure about anything here, because I can't seem to find schematics of this pin at all. Of course the original manual/schematics are gone as well.

This diode seems important for the the display to be working, and it still does even with this thing failing.

#21 6 years ago

Well just to give closure to this thread, the problem was found and solved. At the seller where we got a very fun Starship Troopers, we tried the display in the other batman. It performed just as worse. Then we tried bypassing the driver board, and connectes the display cable from the working DMD: bingo.

The problem was in the square chip socket, it was old and rounded and possibly wasn't making proper contact, causing the problems. The seller was cool and we got the working display.

It was even working in our own Batman Forever, no power problems.

Thanks for the help all!

image.jpg
Promoted items from the Pinside Marketplace
From: $ 40.00
Lighting - Interactive
Professor Pinball
3,300
Sale Pending!
Gardner, MA
$ 10.00
Cabinet - Sound/Speakers
Gweem's Mods
From: $ 5.00
Cabinet - Other
Rock Custom Pinball
3,500 (Firm)
Machine - For Sale
Commack, NY
$ 21.00
Electronics
Yorktown Arcade Supply
From: $ 18.00
Apparel - Men
Pinside Shop
3,200
Machine - For Sale
Bethlehem, PA
From: $ 20.00
Cabinet - Other
Rock Custom Pinball
€ 339.00
Displays
GermanGamingSupplies.com

Hey there! Got a moment?

Great to see you're enjoying Pinside! Did you know Pinside is able to run thanks to donations from our visitors? Please donate to Pinside, support the site and get anext to your username to show for it! Donate to Pinside