I was finally able to find a nicely labelled photo of an Atari Mega ST on atari-computermuseum.de. It's a slightly different version and rev. than mine (this is a rev B Mega 4 and mine is a rev 5 Mega 2), but it's a close enough to figure out which chips are what. I had a surprisingly hard time finding a labelled one like this in the wild.
If I'd paid for this, I would have definitely sent it back, but it was basically free, so I took a crack at cleaning it up and repairing the screwed-up pin tonight.
I think I have it cleaned up pretty well, and I got the pin back to where it's supposed to be. At least now there's a chance I can get it to work. I may give it a go this weekend.
So I "won" this Atari ST 4MB expansion as a BBS attendance prize a few weeks ago.
The board was pretty filthy when it got here, but also, take a look at the 3rd pin from the left in the second picture. It looks like that pin has gotten too hot and somehow pushed through, to where it wouldn't make contact on the MMU (this board is supposed to piggyback the MMU).
Those drives were displaced by these. I finally got them all swapped in/out. right around 200 drives.
Finally took the time last night to get Total Replay installed on my Apple IIe / Microdrive Turbo.
I looked for a tutorial, but didn't find find one right away, so I basically decided to fool around with Ciderpress and the Compact flash from the Microdrive until i figured it out.
It wasn't difficult once I got my head into it and worked through it.
Now I have a second partition on my IIe with 200+ games ready to go at a moment's notice.
I also found some good info on the watchdog timer here, but the info here is from 2013, so you have to keep in mind that some of the device / driver names have changed.
Unfortunately, there's a lot of misleading information on the watchdog timer..in part because the device and kernal modules have changed between models of Pi and versions of Raspbian. I found the information I needed to get them going here...
I've said this before, but it's worth repeating...
If you use Raspberry Pis on any kind of mass scale, learn about and use the built-in Broadcom watchdog timer.
It has completely mitigated any inherent instability in the Pis I run as PAC kiosks. I've had almost 80 of these things (mostly 3B+) running 24x7 across several locations(some in children's areas) for over a year,and I've only had to physically touch one one time, and that was because there was a key on the keyboard physically stuck.