Atari POKEY
The Pot Keyboard Integrated Circuit (POKEY) is a digital I/O chip found in the Atari 8-bit family of home computers and many arcade games in the 1980s. It was commonly used to sample (ADC) potentiometers (such as game paddles) and scan matrices of switches (such as a computer keyboard). POKEY is also well known for its sound effect and music generation capabilities, producing a distinctive square wave sound popular among chip tune aficionados. The LSI chip has 40 pins and is identified as C012294. POKEY was designed by Atari employee Doug Neubauer, who also programmed the original Star Raiders.
Some of Atari's arcade systems use multi-core versions with 2 or 4 POKEY chips in a single package for more sound voices. The Atari 7800 allows a game cartridge to contain a POKEY, providing better sound than the system's audio chip. Only two games make use of this: the ports of Ballblazer and Commando.
The USPTO granted U.S. Patent 4,314,236 to Atari on February 2, 1982 for an "Apparatus for producing a plurality of audio sound effects". This referred to POKEY's sound generation abilities. The inventors listed were Steven T. Mayer and Ronald E. Milner.
No longer manufactured, POKEY is now emulated in software by classic arcade and Atari 8-bit emulators and with the SAP player [1].
by part number
The Atari 8-bit computers map POKEY to the $D2xxhex page and the Atari 5200 console maps it to the $E8xxhex page.
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