Just wanted to share something I observed with Spike II code that inadvertently got myself into. Last summer I got a replacement CPU board for my Star Wars Pro to help troubleshoot a sound issue (which ended up being a spike II software issue in the end), the replacement board had an SD card in it already, which I forgot to check when I swapped it in. It turned out this SD card had Aerosmith LE installed on it. So when I powered up my game the first time it booted to Aerosmith, did the attract mode and everything, and you could even start a game, though I only plunged the ball and flipped at it once or twice out of curiosity and then figured this can’t be good for the node boards.
I swapped the Star Wars SD card back in and everything seemed to be working again, but Somehow the node board responsible for the inner loop on my game got its code messed up from the Aerosmith code and would misfire the posts during the Lightsaber duel mode so you could never finish it.
I tried downgrading to 1.03 and another earlier version and none of these worked. By some miracle I had a copy of .90 on my computer, so tried it back down to .90 so it would force a downgrade to the node boards which seemed to finally reset the behaviour I was seeing. I was then able to upgrade back to 1.04 and had no further issues.
It seems not every code update changes node board programming, so when the machine was swapped back from Aerosmith to Star Wars, it must do a firmware version check on the nodeboards during the boot sequence and saw a version number that was high enough, and didn’t bother flashing the node boards to the latest Star Wars version.
So long story short, I wouldn’t try putting Premium/LE code on a pro game, it might mess up your node boards in a bad way, maybe send the wrong amount of voltage to a coil that is different between the versions of the game and cook something. I was really lucky in my case I didn’t mess anything up permanently.
On a SAM game, I’d be curious if the switch or coil matrix is similar between the Pro and Premium/LE versions enough that you could just wire in the column and row for switches for a feature and it would possibly work if you had a way to get the code on the machine installed? Think of Spinners on Metallica for example...