(Topic ID: 200893)

Judge Dredd CPU crashing issues


By arolden

2 years ago



Topic Stats

  • 5 posts
  • 3 Pinsiders participating
  • Latest reply 2 years ago by arolden
  • Topic is favorited by 1 Pinsider

You

Linked Games

#1 2 years ago

Hi all.

I am hoping you guys can give me some guidance on a weird reset issue with my JD. I cleared up a few opto issues and problems with the sound board. After that the game refused to boot, or it would turn on for 10-20 seconds and then reset. During the resets D19 was lit, D20 was out and D21 was lit.

Pressing on the ASIC chip seemed to help and after another reset it played fine for an hour. Then after restarting it, I had another reset but it was good for another hour after that. It seems like the resets only occur in the first few minutes after power on. No issues with the 5 volt circuit - it's steady at 5.3 volts.

So where should I focus on troubleshooting? Is it likely time to resocket and replace the ASIC? Anything else that could be contributing to these issues?

#2 2 years ago

Reseat the ASIC and reseat/replace the power connector to the cpu board.

#3 2 years ago
Quoted from RonaldRayGun:

Reseat the ASIC and reseat/replace the power connector to the cpu board.

Make sure you have the MPU removed from the game when pressing on the ASIC, doing this with the board installed can lead to other issues like cracked traces.

Does the MPU exhibit this same behavior with ALL of the cables removed except for power?

Quoted from arolden:

It seems like the resets only occur in the first few minutes after power on.

This is a longshot, but you could be seeing a problem related to a failing thermistor in the power box, the thermistor is there to act as a current limiter on power on, but it heats up quickly and should stop limiting current within the first couple seconds of startup.

#4 2 years ago

Thanks for the suggestions so far. I have tried them all but they made no difference.

So I swapped the power driver boards between my JD and DM. DM driver board works fine in JD. No resets.

The JD board also has reset issues when in DM. In fact, it resets even more frequently in DM. It is hard to even start a game; sometimes it resets straight after it resets. The 5 volt circuit is running at 5.35 volts and does not drop (visibly) when the resets occur.

So where should I go from here? I am thinking that, since my voltages are actually OK, this might be an issue with the LM323K regulator. Thoughts?

#5 2 years ago

I think I've fixed it. I reflowed solder on J101, J102, J103, fuse 113, and the LM323K regulator. No resets and TP2 is now the same as JD at around 5.75 volts. Not sure which of the solder joints was flaky, but at least they're all redone now.

Promoted items from the Pinside Marketplace
From: $ 233.10
From: $ 18.00
Apparel - Men
Pinside Shop

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