A digital I/O chip that handles the serial I/O bus, audio generation, keyboard scan-, and random number generation. POKEY also digitizes the resistive paddle inputs and controls maskable Interrupt (IRQ) requests.
The Atari Pokey is a computer chip that is used to generate sound in arcade games, home computers and game consoles. It was originally designed for the Atari 5200 video game system, but used in many of their arcade games. It is also used for serial I/O, processing keyboard input, generating random numbers, processing paddle input, and processing interrupt requests.