Chips › Sound & audio › Wavetable & sample › MOS 6581/8580 SID

MOS 6581/8580 SID

1982

MOS Technology's celebrated Commodore 64 sound chip, offering three analogue voices with filters that defined 1980s home-computer music.

Emulators

EmulatorTypeLicenseSite
C64 ForeverdownloadableCommercial
CCS64downloadableShareware
DenisedownloadableFreeware
Emu64downloadableGPL-3.0
FrododownloadableGPL-2.0
Hoxs64downloadableFreeware
Micro64downloadableFreeware
Power64downloadableShareware
VICEdownloadableGPL-2.0
VirtualC64downloadableGPL-3.0
XemudownloadableGPL-2.0
YACE64downloadableFreeware
Z64KdownloadableFreeware
c128onlineMITWebsite ↗
c64jsonlineMITWebsite ↗

Machines

Commodore 128

Commodore 128D

Commodore 64 (breadbin)

Commodore 64C

Commodore SX-64

MEGA65

Operating systems

CP/M 3.0 (Plus)

GEOS 1.0

GEOS 2.0

Reference & documentation

External technical references for programming MOS 6581/8580 SID and for writing emulators.

ResourceTypeNotes
MOS 6581 SID Datasheet (PDF) ↗DatasheetOriginal Commodore datasheet: registers, pinout, timing
C64-Wiki: SID Register Map ↗Memory mapAll 29 registers at $D400 with descriptions
SID 6581/8580 Pinout and Signals ↗PinoutPin assignments and signal descriptions
Codebase64: SID Programming ↗ProgrammingAssembly guides: waveforms, frequencies, model detection
Classic Hard-Restart and the ADSR Bug ↗ProgrammingLFSR envelope timing and ADSR-bug workaround
SID_schematics Wiki - Chip Internals ↗ReferenceReverse-engineered envelope, waveform, filter, ADSR-bug internals
MOS Technology 6581 (Wikipedia) ↗ReferenceArchitecture overview and 6581 vs 8580 differences
SID_schematics - Silicon-Level Schematics ↗SchematicFull 6581/8580 schematics traced from die photos
reSID Source (libsidplayfp) ↗SourceCycle-accurate C++ SID emulator source code