Battlezone (Arcade)

The original tank simulator.

Anti-Piracy#

Due to a rise of copies and pirated arcade cabinets of previous games, Atari made increased efforts to prevent such cases in their arcade games starting from the 1980s. The game computes a checksum with the drawing command for the copyright string on the title screen, and stores the result at 0x02ed. If this value is not 0 or 1, saucers will not sound after the player obtains 100,000 points, making gameplay much harder later on.

The game also checks for a valid POKEY chip and hangs when generating a random number if it is not detected.