	community	directory	books	authors	images	encyclopedia

Email:
Password:
Register

Knowledgerush Search

Message boards Post comment

POKEY

Atari POKEY (C012294) pin-out

The Atari POKEY is a digital I/O chip found in the Atari 8-bit family of home computers and many arcade games in the 1980s. Its name comes from POtentiometer and KEYboard, as it was commonly used to sample (ADC) potentiometers (such a 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 afficionados. The LSI chip has 40 pins and is identified as C012294.

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 emulated in software by classic arcade emulators (e.g. MAME) and Atari 8-bit emulators.

Features

audio
- 4 semi-independent audio channels
- channels may be configured as one of:
  - four 8-bit channels
  - two 16-bit channels
  - one 16-bit channel and two 8-bit channels
- per-channel volume, frequency, and waveform (square wave with variable duty cycle or polynomial noise)
- high-pass filter
keyboard scan (up to 64 keys)
pot ports (8 independent ports, each with 8-bit resolution)
timers (audio channels 1, 2, and 4 can be configured to cause timer interrupts when they cross zero)
random number generator (8 or 9 bits of a 17-bit polynomial counter can be read)
serial I/O port
IRQ interrupts

Compose Your Message

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "POKEY".