Dig Dug vertical lines on characters and text

bobwired

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This recently happened and I dont think its a monitor issue. I left the game on longer than I normally would and this started happening. It doesnt seem to effect the background, only the text and characters. Hard to see on cell phone pic, but If a photo helps, I will post one.
 
Those black lines in the first photo are an artifact of my cell phone camera. As well as the scan lines in the next for pics. Attached are the photos. Anyone know which roms drive specifically the characters and text?
 

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I, too have a board doing this same thing and I havent figured it out yet.

Sorry I cant be of much more help, haha.
 
Motion RAM is not tested by self test.

On a Galaga this would be the 2147/2148 RAMs... I'd have to look at the Dig Dug schematic to see what it would be for that boardset.

RJ
 
How would I check them?

I went and pulled my DigDug board to have a look over and it turns out I have the same board you do. So.. that's nice. What's not nice is that RAM isn't socketed. More over, I'm not 100% sure what the replacement RAM for these would be. My board has a 6560N at 11C and a DM74S289N at 12C. Both are RAM and, according to the manual, are the same part number. So I know either of those will work as a replacement. But I'm not sure where to get a replacement RAM that would work in their spots.

If you can touch the board and see the monitor... there is a quick, unreliable, but quick ghetto test that MIGHT help you figure out which is bad. I've had it work a couple of times for me with RAM; With the game on, and standing/sitting where you can see the screen while it's running... touch the back of the RAM and watch the screen. If there's a goofy and/or dead line on the RAM you touching it will give enough interference to see something on the screen... the dead lines in the graphics might shift a little, or fill with static... just something to let you know you're in the right place. It should only do that on the bad RAM. So, if you touch all the pins on the back of 12C and nothing happens, but you touch all the pins on the back of 11C and the lines change... tada. ... granted, that doesn't work all the time.

Hopefully someone will chime in with the replacement part numbers for those RAM?
 
Ill try it. Trying to setup some sort of mirror to view, any ideas?

Okay, it looks like I was (surprise surprise...) wrong. Wrong RAM.

7A and 9B are the ones you should be looking at I think (again... le sigh). When I pulled out my Dig Dug board to check something out the first time I decided to work on it to see if I could get it working. When I was looking through the schematics (and not just RAM lists from that first PDF link), it looks like 7A and 9B (2148's) are in the motion object circuit. Sooo... those are the ones to check. The other (11C, 12C) are part of... something else, already forgot. But, that's nice because 2148's are easy to find. :)

Sooooo... yeah, sorry about that.

... on the plus side, I did get my board running. So... yay?

EDIT/SIDENOTE: WTF? They couldn't settle on what type of EPROM they wanted to use? 2716's, 2732's, 2532's... all just mixed in. Made checking them a huge pain in the arse.
 
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Well, Ive succeeded in making it worse. I was reaching through the coin mech door touching the ic's and now it just boots to some blotchy screen with a constant tone.(or keeps rebooting all together) I guess its time to send it off for repair.
 
Ok, finally after some tinkering, I was able to get it to boot, and got a rom error. Reseated it and Im back to a functioning machine. But still with the stripes/loss of green? Trying to get klassic to sell me his spare board.
 
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