I’ve got a Black Hole that every now and then “freezes up”. It has never happened during a game in 3-4 years, but only during attract mode. However, it happens infrequently enough that I would say I’ve just been lucky in that regard.

When it freezes, the controlled lamps will stop cycling for attract mode, and one or two of the displays will usually be displaying a single digit that appears to be very bright. The side gate stops cycling, but the infinity lights still rotate. There is no more sound going on.

I’ve done all the ground mods on the unit, replaced the orange electrolytic cap, completely rebuilt the CPU board in the battery area, as there was a fair amount of corrosion. That went well, and the board fired up right away afterwards.

I’ve suspected that I might have some instability on my 5V supply, so I’ve monitored it with a scope, set to capture if the 5V dips below 4.7V. I’ve had lockups and no captures, so I don’t think that’s the problem. I’ve also use the trim pot on the power board to turn the 5V up to 5.2, to give a bit more of a cushion, but it still locks up.

Does anyone have any suggestions on what to look for next? I’ve got the tools available to get this done, but I just kind of feel like I’m hitting a wall. Any extra guidance of what I should look for next would be greatly appreciated.

Thanks,
Jeff

There is no reset board present, so no, it's not connected.

I just jiggled all the CPU connectors, and it was solid. Wait 20 mins, and it freezes up. When this happens, I check the address lines, and they’re all high. Didn’t check the data lines, but I would suspect no action there...what is that telling me?

Thanks for the pointers, Chris. I’ll check out the temps on the chips next time I get it to lock up. You’re referring to U4/5/6, right?

I’ve already installed the GPE Sys 80 corrosion repair kit last summer, along with cleaning up any corrosion associated with these parts. Looks like I’ll need to expand the zone a bit and pull up the soldered-in CPU chip. Not as big of a deal for me anymore, now that I have a de-soldering gun and have learned how to use it. When I get a chance, I’ll pull up the CPU and the SW2 bank. Maybe Z9 and Z10, as well, and see if there’s any corrosion under them.

I’ve also got access to what appears to be a corrosion-free gen 1 Sys 80 board. Don’t know if it works. There is no software in it, nor RIOT chips, and while it seems I’d need to do a few mods to make it work with modern chips, I don’t have access to the software to program onto the ROMs for U2/U3. Any suggestions there?

I’ll likely start with trying to get my mostly-working board to be a fully-working board, but I’ll keep that other board in my back pocket if I can’t turn anything up on that (unless it’s easier to update that spare board than I realize).

Thanks,
Jeff

Here's a pic. Pretty sure the 4 chips in the top left will need to go. They weren't part of the GPE kit, so I left them hoping they were good enough. Bad decision, I know.

Gen 1 bd has sockets at U2/U3, but no chips. I could steal the game prom from main bd (after mod) but where can I get these chips or files for them?

20181215_063919 (resized).jpg

Update: I got replacement parts for those 4 chips in the upper left (Z7 - Z10) and the main CPU. Removed the old ones, cleaned up the board, put new in, and now it’s been running without problems for a couple days, including through our NYE party. I’m not ready to call it fixed yet, but I’m pretty optimistic.