One of the most important things we can do as a society is make videos of things, take photos of things, and share them for the world to see, you never quite know when what you’ve done might come in handy, or prove to be the only remaining reference that something once existed, it continues to amaze me how even things that were at one point popular are now difficult to find any visible trace of now.
This is true of arcade games as much as anything else, and I Know when looking at the fruit machine and other non-video games the situation is even worse, sometimes not a single photo of a machine anywhere.
While looking at Mega System 1 it was noted in the source that the game P47 sets some other bits during the Jaleco logo, effect unknown. Luckily, in this instance there was a video on YouTube of P47 booting up. It’s a terrible quality video, but it still gave us an idea of what was missing.
some kind of trail effect…
I poked around with the code a bit, and have attempted to implement this in MAME.
I don’t know if this is actually correct, at the point where they want the trails to vanish they adjust a parameter, the original video isn’t really clear enough to show how the trails are removed, so I’ve had to guess. If anybody has a P47 PCB and can record a better quality video it would be appreciated, the one on YouTube was more useful than the original poster probably ever thought it would be, but not really good enough to say my emulation is correct :-)