Another fun little video from Retro Game Mechanics Explained, on youtube, describing the steps the Atari Tempest arcade game programmers took to combat piracy.

https://youtu.be/ewoDLDDgHkI

I think it's funny how they used the behavior of the POKEY chip to determine if the game was running on genuine Atari hardware, when the whole game relies on the Atari Quadrascan vector processor (another vid https://youtu.be/smStEPSRKBs) to display!

I don't know, but I would imagine that bit of code is recycled between many Atari games of the time.

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