So
@mhavoc is going to know for sure here but I believe the squares are on purpose to avoid activation of the spot killer circuit on certain screens. There's a work loop called waste time in the code and that's what I recall anyway.
These are definitely on purpose.
@Kaworu5 checked this for me on an FPGA and it does the same thing.
Now then.
Some steps forward, some steps back, mostly forward.
The Good:
After chasing my tail for hours/days/weeks, I have come to the conclusion that the
runtime instability is the damn
SEEQ eproms. No matter how clean and oxidization free they are. No matter the fact that they read good in self test and in the programmer. They. Freaking. Suck.
How I arrived to this conclusion. I burned an entire new set of EPROMS, and started pulling and replacing sub groups. Alpha Group, no change. Gamme Group, no change. ALL ROMS, and then it ran for an hour without resets. I thought about it more, and then replaced all the SEEQ ROMS only. That seemed to still be running good.
Yesterday, I ran the thing for five hours and it didn't crash or reset at all once it got going*. So I'm crossing fingers on the EPROM issues here.
It had some audio issues I noticed at the end of that run, with some incorrect sounds, but I identified that as a lose LS245. Sounds seem good currently.
The Bad:
For whatever reason, it's still freaking out when first turned on cold. The first ~30-60 seconds, it's kinda unstable. Takes a few seconds to boot initially, and then it can reset a few times. However, once it's "warmed up" it's rock solid. I ran it all afternoon yesterday with one credit on the counter and it stayed there. Same thing today. At the point that it's "warmed up" if I cycle power to the cabinet, it will come back up immediately and not reset or display any weird behaviors. So I'm wondering what's going on there.
I'm mad at this whole ROM thing. I'm an idiot and it cost me a lot of unnecessary time, work, and socketing that probably introduced more problems from just manipulating the board.
So:
Intermittent Box -> Normal
Runtime Instability -> SEEQ ROMS suck
Boot Instability -> ???
Sound Issues -> LS245 Bad Socket