Programmable sound generator

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A programmable sound generator, or PSG, is a sound chip that generates sound waves by synthesizing multiple basic waveforms, and often some kind of noise generator (all controlled by writing data to dedicated registers in the sound chip, hence the name) and combining and mixing these waveforms into a complex waveform, then shaping the amplitude envelope of the resulting waveform using attack, decay, sustain, and release time periods, so that the resulting waveform then mimics a certain kind of sound.

A sound chip is an integrated circuit designed to produce sound. It might do this through digital, analog or mixed-mode electronics. Sound chips normally contain things like oscillators, envelope controllers, samplers, filters and amplifiers. During the late 20th century, sound chips were widely used in arcade game system boards, video game consoles, home computers, and PC sound cards.

Envelope (waves) function describing the extremes of an oscillating signal

In physics and engineering, the envelope of an oscillating signal is a smooth curve outlining its extremes. The envelope thus generalizes the concept of a constant amplitude. The figure illustrates a modulated sine wave varying between an upper and a lower envelope. The envelope function may be a function of time, space, angle, or indeed of any variable.

They were, and are, often used in arcade games, game consoles, and home computers.

Arcade game coin-operated entertainment machine

An arcade game or coin-op game is a coin-operated entertainment machine typically installed in public businesses such as restaurants, bars and amusement arcades. Most arcade games are video games, pinball machines, electro-mechanical games, redemption games or merchandisers. While exact dates are debated, the golden age of arcade video games is usually defined as a period beginning sometime in the late 1970s and ending sometime in the mid-1980s. Excluding a brief resurgence in the early 1990s, the arcade industry subsequently declined in the Western hemisphere as competing home video game consoles such as the Sony PlayStation and Microsoft Xbox increased in their graphics and game-play capability and decreased in cost.

Home computer class of microcomputers

Home computers were a class of microcomputers that entered the market in 1977, that started with what Byte Magazine called the "trinity of 1977", and which became common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a single nontechnical user. These computers were a distinct market segment that typically cost much less than business, scientific or engineering-oriented computers of the time such as the IBM PC, and were generally less powerful in terms of memory and expandability. However, a home computer often had better graphics and sound than contemporary business computers. Their most common uses were playing video games, but they were also regularly used for word processing, doing homework, and programming.


The most used (canonical example) was the AY-3-8910 from General Instrument (or its derivatives AY-3-8912/AY-3-8913), the SN76489 from Texas Instruments and the Yamaha YM2149, a AY-3-8910 made under license. Yamaha also brought out the YM2203 and YM2608 chips on the market, these were also capable of FM synthesis. A chip made by Toshiba called the PSG also found broad use, especially in several generations of MSX-computers.

The concept of canon is very broad; in a general sense it refers to being one (adjectival) or a group (noun) of official, authentic or approved rules or laws, particularly ecclesiastical; or group of official, authentic, or approved literary or artistic works, such as the literature of a particular author, of a particular genre, or a particular group of relgious scriptural texts,, or similarly, one or a body of rules, principles, or standards accepted as axiomatic and universally binding in a relgiion, or a field of study or art. This can be related to such topics as literary canons, a topic within itelf, for which see canon (disambiguation)#Literature.

General Instrument AY-3-8910 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 were used in many arcade games—Konami's Gyruss contains five—and 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, 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.

Texas Instruments SN76489 programmable sound generator chip

The SN76489 Digital Complex Sound Generator (DCSG) is a TTL-compatible programmable sound generator chip from Texas Instruments. It contains:

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The Mockingboard is a sound card for the Apple II family of microcomputers built by Sweet Micro Systems. The standard Apple II machines never had particularly good sound, especially when compared to competitors like the SID chip-featuring Commodore 64. With the notable exception of the Apple IIGS, all an Apple II programmer could do was to form sounds out of single clicks sent to the speaker at specific moments, which made the creation of complex sounds extremely difficult to program and made it mostly impossible to do any other processing during the creation of sounds. Early (1978) hardware accessories such as ALF's Apple Music Synthesizer focused on producing only music. In 1981, Sweet Micro Systems began designing products not only for creating music, but speech and general sound effects as well. Its specialized hardware allowed programmers to create complex, high-quality sound without need for constant CPU attention. The Mockingboard could be connected to the Apple's built-in speaker or to external speakers. However, as the quality of the built-in speaker was not high, the instruction manual recommended obtaining external speakers.

Yamaha YM2612

The YM2612, a.k.a. OPN2, is a sound chip developed by Yamaha. It belongs to Yamaha's OPN family of FM synthesis chips used in several game and computer systems.

Yamaha YM3812

The Yamaha YM3812, also known as the OPL2, is a sound chip created by Yamaha Corporation in 1985 and famous for its wide use in IBM PC-based sound cards such as the AdLib, Sound Blaster and Pro AudioSpectrum (8bit), as well as several arcade games by Nichibutsu, Toaplan and others.

Yamaha DX7 synthesizer model

The Yamaha DX7 is a synthesizer manufactured by the Yamaha Corporation from 1983 to 1989. It was the first commercially successful digital synthesizer and became one of the bestselling synthesizers in history, selling over 200,000 units.

Yamaha YMF262

The Yamaha YMF262, also known as the OPL3, is an FM synthesis sound chip released by Yamaha Corporation in the early 1990s. It is an improved version of the Yamaha YM3812 (OPL2). It was used in a number IBM PC soundcards including Sound Blaster 16 and Pro AudioSpectrum (16bit).

Philips SAA1099

The Philips SAA1099 sound generator was a 6-voice sound chip used by some 1980s devices, notably:

Yamaha YM2413

The YM2413, a.k.a. OPLL, is a cost-reduced FM synthesis sound chip manufactured by Yamaha Corporation and based on their YM3812 (OPL2). To make the chip cheaper to manufacture, many of the internal registers were removed. The result of this is that the YM2413 can only play one user-defined instrument at a time; the other 15 instrument settings are hard-coded and cannot be altered by the user. There were other cost-cutting modifications: the number of waveforms was reduced to two, and the channels are not mixed using an adder; instead, the chip's DAC uses time-division multiplexing to play short segments of each channel in sequence, as also done in the YM2612.

The Namco System 86 is an 8-bit arcade system board which was first used by Namco in 1986; it was the first board from that company to use a Yamaha YM2151 FM sound chip, and was succeeded by the more powerful Namco System 1 arcade system board when the company went 16-bit in 1987.

Konami GX400 is an arcade system board by Konami that made its debut in 1985.

Yamaha YM2151 eight-channel, four-operator sound chip

The Yamaha YM2151, also known as OPM is an eight-channel, four-operator sound chip. It was Yamaha's first single-chip FM synthesis implementation, being created originally for some of the Yamaha DX series of keyboards. Yamaha also used it in some of their budget-priced electric pianos, such as the YPR-7, -8, and -9.

The Elektor TV Games Computer was a programmable computer system sold by Elektor in kit form from 1979. It used the Signetics 2650 CPU with the Signetics 2636 PVI for graphics and sound. These were the same chips as used in the Interton VC 4000 console family. A 2K monitor ROM written by Philips and a cassette interface were the most important differences between the TVGC and the Interton family. Many VC 4000 games were adapted versions of TV Games Computer games. It is possible to add cartridge slots to the TVGC to enable it to play console games, and the Hobby Module of the Acetronic console effectively transforms it into a basic TVGC.

An MSX-ENGINE chip is a specially developed integrated circuit for home computers that are built according to the MSX specifications. Generally, such a chip combines the functions of many separate, older/simpler chips into one. This is done to reduce required circuit board space, power consumption, and production costs for complete systems.

Yamaha YM2203

The YM2203, a.k.a. OPN, is a three-channel sound chip developed by Yamaha. It was the progenitor of Yamaha's OPN family of FM synthesis chips used in many videogame and computer systems throughout the 1980s and early 1990s. The YM2203 itself was used in a variety of NEC computers, along with various arcade game machines.

Yamaha YM2608

YM2608, a.k.a. OPNA, is a sixteen-channel sound chip developed by Yamaha. It's a member of Yamaha's OPN family of FM synthesis chips, and the successor to the YM2203. It was notably used in NEC's PC-8801/PC-9801 series computers.

Yamaha YM2164

The Yamaha YM2164 a.k.a.OPP, is an FM synthesis sound chip developed by Yamaha, an enhanced version of their YM2151 a.k.a. OPM. The OPP was used in various MIDI-based synthesizers by Yamaha - DX21, DX27, DX100, SFG-05, FB-01 - plus several licensed products: the IBM Music Feature Card and Korg's DS-8 and Korg 707.

The Yamaha YMF278B, also known as the OPL4, is a sound chip that incorporates both FM synthesis and sample-based synthesis.


The Panasonic FS-A1WSX was the last MSX2+ made by Panasonic. It was the successor of FS-A1WX and incorporated few changes like S-Video output, no tape support, color printer support and an improved A1 Internal Cockpit software with a Kanji color word processor.