TTL Heaven!
Jeezus look at all that LS / TTL decode logic, 74154 and all these latches, counters and w.h.y. It's been a very long time.... had me reaching for the manuals, um, Google as i'd forgotten what a 74166 and what not did! Excellent.
Tomohiro Nishikado already had a string of almost a dozen arcade games under his belt when he started on what was to become the best remembered - certainly the most played - game he was ever to create: Space Invaders, released in Japan 35 years ago this month. Nishikado was an engineer who had joined vending machine company …
I met Tomohiro Nishikado while working at Software Creations (Manchester) in 1990... he was a polite, humble small gentleman but I still bowed to him as if he was a god!
Space Invaders was a game that set the stage for future gaming creations and Tomohiro was quite simply a genius of his time and in my heart and mind he still is.
Played this in City Poly college bar in '78, never got as good as the experts but still managed some reasonable scores. Counting shots was the key to getting maximum points from downing the mystery ships at the top (was it 21, then 13?).
Never really liked any of the other versions - this was perfection.
...get them to move properly! If they only studied the game even slightly they'll realise that one moves every frame, making the speed up natural when their numbers decrease.
And the bass movement sounds are four semitones around D! ( Oh crap, I never thought I would actually write that down ;) )