Tangentially related, when I was slaving away at Dickinson College, there
were three arcade machines in town; one of them was Tempest. I must have
put about a thousand dollars worth of quarters in it.
I could never figure out how it was coded; I didn't have the mad skillz to
write it, and this really bugged me. A few years ago I grabbed a ROM dump
and reverse engineered the source code to the point where I could
understand the game engine.
https://github.com/charlesUnixPro/Tempest-Source-Code
-- Charles