General Instrument AY-3-8910

The AY-3-8910 is a 3-voice programmable sound generator (PSG) designed by General Instrument (GI) in 1978, initially for use with their 16-bit CP1610 or one of the PIC1650 series of 8-bit microcomputers. It has three channels of sound with a wide frequency response that can produce almost all of the notes on an 88-key piano. These can be modified by a shared envelope generator and random noise channel that can be added to produce sound effects.

The AY-3-8910 and its variants were used in many arcade video game—Konami's Gyruss contains five—and Bally pinball machines as well as being the sound chip in the Intellivision and Vectrex video game consoles, and the Amstrad CPC, Oric-1, Colour Genie, Elektor TV Games Computer, MSX, Tiki 100 and later ZX Spectrum home computers. It was also used in the Mockingboard and Cricket sound cards for the Apple II and the Speech/Sound Cartridge for the TRS-80 Color Computer.

After GI's spinoff of Microchip Technology in 1987, the chip was sold for a few years under the Microchip brand. It was also manufactured under license by Yamaha (with a selectable clock divider pin and a double-resolution and double-rate volume envelope table) as the YM2149F; the Atari ST uses this version. The chips are no longer made, but functionally-identical clones are still in active production. An unofficial VHDL description based on the YM2149 is freely available for use with FPGAs.