From Video Game Music Preservation Foundation Wiki
Jump to: navigation, search
SN76477N - Bare.jpg
Developer: Texas Instruments
Released: 1978-??-??
Type: Chip

1.) Sine Wave or Pulse Wave or Noise

The SN76477, known as the CSG (complex sound generator), is a PSGs designed by Texas Instruments and released in 1978. The chip is capable of processing a single audio channel either as analog (sine wave), digital (pulse wave), or as noise output. The audio channel also features envelope control and attack and decay adjustments. Despite TI calling the chip a complex sound generator, difficulty implementing the chip led to it mostly being used for sound effects, though primitive music was possible. The chip's life was short-lived because TI released the 3-channel SN76489 a couple years later which was capable of competing with the extremely popular AY-3-8910.

The chip's technical manual was released in July of 1978, but the first game to use the chip, Space Invaders, was released in June, indicating that the chip was released earlier in the year.


The SN76477 was manufactured in two different sizes which are signified by the model number. SN76477N (narrow) uses a standard 0.6" width dual in-line package (DIP). The less-popular SN76477NF uses a 0.4" width DIP. Despite the changes in the size of the casing, the internal chip was identical.

The chip was cloned with the very similar ICS76477.


The SN76477 was used in the ABC 80 home computer as well as several electronic devices in the late 1970s and early 1980s.

Release Device Chip
1979-??-?? ABC 80  ?


The SN76477 was used in around 40 arcade games and pinball machines, the very first of which was probably Space Invaders, made by Taito. Taito would continue to use the chip more than any other company, although it was also used in a handful of SNK games. The specific type of chip (N or NF) will be noted below.

Release Game Chip Sample
1978-06-?? Space Invaders (ARC) SB76477N (Code missing) No Music
1978-??-?? Claybuster (ARC)  ?
1979-??-?? Cosmo (ARC)  ? No Music
1979-??-?? Family Fun! (ARC)  ?
1979-??-?? Galaxy Wars (ARC)  ? No Music
1979-??-?? Ozma Wars (ARC)  ? No Music
1979-??-?? Rotary Fighter (ARC)  ? No Music
1979-??-?? Sky Love (ARC)  ? No Music
1979-??-?? Sheriff (ARC)  ?
1979-??-?? Shuttle Invader (ARC) SN76477N No Music
1979-??-?? Space Chaser (ARC)  ? No Music
1979-??-?? Space Fever (ARC) SN76477N
1979-??-?? Space Fever High Splitter (ARC)  ?
1979-??-?? Space Launcher (ARC)  ?
1979-??-?? Spectra IV (PBL)  ?
1979-??-?? Star Trip (PBL)  ?
1979-??-?? Vegas (PBL)  ?
1979-??-?? Yosaku To Donbei (ARC)  ? No Music
1980-08-?? Stratovox (ARC)  ?
1980-??-?? Balloon Bomber (ARC)  ? No Music
1980-??-?? Crazy Balloon (ARC)  ?
1980-??-?? Gun Champ (ARC)  ?
1980-??-?? Indian Battle (ARC)  ?
1980-??-?? Lupin III (ARC)  ?
1980-??-?? Sasuke vs. Commander (ARC)  ? x3
1980-??-?? Space Encounters (ARC)  ? No Music
1980-??-?? Space Invaders II (ARC)  ? No Music
1980-??-?? Space Laser (ARC)  ? No Music
1980-??-?? Steel Worker (ARC)  ? No Music
1980-??-?? Tomahawk 777 (ARC)  ? No Music
1980-??-?? Tora Tora (ARC)  ? x2
1980-??-?? Vortex (ARC)  ? No Music
1981-??-?? Fantasy (ARC)  ?
1981-??-?? Laser Battle (ARC)  ?
1981-??-?? Zarzon (ARC)  ?
1981-??-?? Vanguard (ARC)  ? x2
1882-??-?? Nibbler (ARC)  ?
1982-??-?? Pioneer Balloon (ARC)  ?
18??-??-?? Malzak (ARC)  ? x2


Document Download
Manual Download - (info)

Picture Gallery

Emulation Status

The chip has been emulated a couple times.

  • MAME has emulated the chip for the various arcade games that require it.
  • Any ABC 80 emulator with audio support will have emulated the chip.