General Instrument AY-3-8910

The AY-3-8910 is a 3-voice programmable sound generator (PSG) designed by General Instrument in 1978, initially for use with their 16-bit CP1610 or one of the PIC1650 series of 8-bit microcomputers. The AY-3-8910 and its variants became popular chips in many arcade games and pinball machines, and were used on, among others, the Intellivision and Vectrex video game consoles, Amstrad CPC, Oric 1, Colour Genie, Elektor TV Games Computer, MSX and Sinclair ZX Spectrum 128/+2/+3 home computers as well as the Mockingboard and Cricket sound cards for the Apple II family.

After General Instrument's spinoff of Microchip Technology in 1987, the chip was sold for a few years under the Microchip brand instead. It was also produced under license by Yamaha (with minor modifications, i.e. a selectable clock divider pin, and a double-resolution but double-rate volume envelope table) as the YM2149F; the Atari ST uses this version. It produced very similar results to the Texas Instruments SN76489 and was on the market for a similar period.

The chips are no longer made, but a declining stock is still obtainable for servicing vintage machines. Functionally-identical clone chips are still in active production (see Variants). A VHDL equivalent description has been written, for use in FPGA recreations of arcade machines and others like those mentioned above. The VHDL source code is available on the Internet, and compiles to fill about 10% of a Xilinx XC2S300 FPGA.

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