Editing MOS Technology 6581 (section)

== Reimplementations and derivatives ==

=== Emulation ===
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* In 1989 on the Amiga computer, the demo "The 100 Most Remembered C64 Tunes" and later the PlaySID application was released, developed by [[Per Håkan Sundell]] and Ron Birk. This was one of the first attempts to emulate the SID in software only, and also introduced the file format for representing songs made on the C64 using the SID chip. This later spawned the creation of similar applications for other platforms as well as the creation of a community of people fascinated by SID music, resulting in ''The High Voltage SID Collection'' which contains over 57,000 SID tunes.

A SID file contains the [[MOS Technology 6510|6510]] program code and associated data needed to replay the music on the SID. The SID files have the [[MIME]] media type <code>audio/prs.sid</code>.

The actual file format of a SID file has had several versions. The older standard is PSID (current version V4). The newer standard, RSID, is intended for music that requires a more complete emulation of the Commodore 64 hardware.<ref name="SIDFormat">{{cite web |url=https://hvsc.c64.org/download/C64Music/DOCUMENTS/SID_file_format.txt |format=TXT |title=SID File Format Description |publisher= High Voltage SID Collection |url-status=live |archive-url=https://web.archive.org/web/20190705131958/https://hvsc.c64.org/download/C64Music/DOCUMENTS/SID_file_format.txt |archive-date=2019-07-05 |access-date=2019-07-05 }}</ref>

The SID file format is not a native format used on the Commodore 64 or 128,<ref name="SIDFormat" /> but a format specifically created for emulator-assisted music players such as ''PlaySID '', ''Sidplay'' and  ''JSidplay2''.<ref name="SFJSidplay2">{{cite web |url=https://sourceforge.net/projects/jsidplay2/ |title=Java SID Player Music Library V2 |author=kenchis |publisher=[[SourceForge]] |url-status=live |archive-url=https://web.archive.org/web/20190705133546/https://sourceforge.net/projects/jsidplay2/ |archive-date=2019-07-05 |access-date=2019-07-05 }}</ref> However, there are loaders like ''RealSIDPlay'' and converters such as ''PSID64''<ref name="SFPSID64">{{cite web |url=http://psid64.sourceforge.net/ |title=PSID64 |author=rolandh |publisher=[[SourceForge]] |url-status=live |archive-url=https://web.archive.org/web/20190705133813/http://psid64.sourceforge.net/ |archive-date=2019-07-05 |access-date=2019-07-05 }}</ref> that make it possible to play a substantial portion of SID files on original Commodore computers.
* SIDPlayer, developed by Christian Bauer and released in 1996 for the [[BeOS]] operating system, was the first SID emulator to replicate the filter section of the SID chip using a second-order [[Infinite impulse response]] filter as an approximation.<ref name="SIDPlayer">{{cite web |url=http://sidplayer.cebix.net/#info |title=SIDPlayer |last=Bauer |first=Christian |url-status=live |archive-url=https://web.archive.org/web/20190705134309/http://sidplayer.cebix.net/ |archive-date=2019-07-05 |access-date=2019-07-05 }}</ref>
* In June 1998, a cycle-based SID emulator engine called [[reSID]] became available. The all-software emulator, available with [[C++]] [[source code]], is licensed under the [[GNU General Public License|GPL]] by the author, [[Dag Lem]]. In 2008, Antti Lankila significantly improved the filter and distortion simulation in reSID.<ref>{{cite web |url=https://bel.fi/~alankila/c64-sw/ |title=JSIDPlay2: a cross-platform SID player and C64 emulator |last=Lankila |first=Antti |url-status=dead |archive-url=https://web.archive.org/web/20120116155333/https://bel.fi/~alankila/c64-sw/ |archive-date=2012-01-16 }}</ref> The improvements were included in [[VICE]] version 2.1 as well.
* In 2007 the JSidplay2 project was released, a pure Java based SID player developed by Ken Händel.<ref name="SFJSidplay2" />

=== Hardware using the SID chip ===

* In 1989 Innovation Computer developed the [[Innovation SSI-2001|Innovation Sound Standard SSI-2001]], an [[IBM PC compatible]] [[sound card]] with a SID chip and a [[game port]]. [[MicroProse]] promised software support for the card, and Commodore BASIC programs that used SID required little conversion to run on [[GW-BASIC]].<ref name="latimer198908">{{cite magazine |title=Innovation Sound Standard |magazine=[[Compute!]] |date=August 1989 |last=Latimer |first=Joey |volume=11 |issue=111 |page=68 |issn=0194-357X |url=https://archive.org/stream/1989-08-compute-magazine/Compute_Issue_111_1989_Aug#page/n69/mode/2up |access-date=2013-11-11 }}</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/TUCNDNJHItw Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20180710033122/https://www.youtube.com/watch?v=TUCNDNJHItw&gl=US&hl=en Wayback Machine]{{cbignore}}: {{Citation|title=Replica Sound Cards - AdLib, Innovation SSI-2001, and SwinSID Ultimate.| date=9 July 2018 |url=https://www.youtube.com/watch?v=TUCNDNJHItw|language=en|access-date=2019-08-01}}{{cbignore}}</ref>
* In 1997, an [[electronic musical instrument]] utilizing the SID chip as its synthesis engine was released. It is called the [[SidStation]], built around the 6581 model SID chip (as opposed to the newer 8580), and it's produced by [[Sweden|Swedish]] company [[Elektron (company)|Elektron]]. As the SID chip had been discontinued for years, Elektron allegedly bought up almost all of the remaining stock. In 2004, Elektron released the [[Monomachine]] pattern-based [[Music sequencer|sequencer]] with optional keyboard.  The Monomachine contains several synthesis engines, including an emulated 6581 oscillator using a [[Digital signal processor|DSP]].
* In 1999 [[HardSID]], another PC sound card, was released. The card uses from one to four SID chips and allows a PC to utilize the sound capabilities of the chip directly, instead of by emulation via generic sound cards (e.g. [[SoundBlaster]]).
* The [[Individual Computers Catweasel|Catweasel]] from [[Germany|German]] company [[Individual Computers]], a [[Peripheral Component Interconnect|PCI]] + Zorro multiformat [[floppy disk]] controller and digital joystick adapter for [[IBM PC compatible|PCs]], [[Apple Macintosh|Macs]], and [[Amiga]]s, includes a hardware SID option, i.e. an option to insert one or two real SID chips in a socket for use when playing <code>.MUS</code> files.
* The MIDIbox SID is a [[MIDI]]-controlled synthesizer which can contain up to eight SID chips. It is a free [[Open-source license|open source]] project using a [[PIC microcontroller]]. Control of the synthesizer is realized with software or via a control panel with knobs, [[light-emitting diode|LEDs]], [[liquid crystal display|LCD]], etc., which may optionally be mounted on a keyboardless Commodore 64 body.
* The Prophet64 is a cartridge for the Commodore 64. It features four separate music applications, mimicking everything from modern sequencers to the [[Roland TB-303]]/[[Roland TR-909|909]] series. With an optional User Port peripheral, the Prophet64 may synchronized to other equipment using [[DIN Sync]] standard (SYNC 24). The website now states "Prophet64 has been replaced with the MSSIAH."<ref>{{Cite web|url=https://www.mssiah.com/|title=MSSIAH Cartridge - MIDI Hardware and Software for the Commodore 64!|website=www.mssiah.com}}</ref>
* The MSSIAH is a cartridge for the Commodore 64 that replaces the Prophet64.
* Artist/hacker Paul Slocum developed the Cynthcart cartridge that enables you to turn your C64 into an analogue synthesizer. Its successor, Cynthcart 2, added MIDI in, out and thru ports.
* The Parallel Port SID Interface allows those with very slim budgets to connect the SID chip to a PC.
*In 2003 a SID interface (and software to play Commodore 64 tunes) was released for the [[Zilog Z80|Z80]] based [[SAM Coupé|Sam Coupé]] computer supporting both the 6581 and the 8580.
* In May 2009 the SID chip was interfaced to the [[BBC Micro]] and [[BBC Master]] range of computers via the 1&nbsp;MHz bus allowing music written for the SID chip on the Commodore 64 to be ported and played on the BBC Micro.
* In October 2009 thrashbarg's project interfaced an SID chip to an ATmega8 to play MIDI files on a MOS 6581 SID.
* In March 2010 STG published the SIDBlaster/USB - an open source, open hardware implementation of the SID that connects to (and is powered by) a [[USB port]], using an FTDI chip for the [[USB]] interface and a PIC to interface the SID.
* In August 2010 SuperSoniqs published the Playsoniq, a cartridge for [[MSX]] computers, with (in addition to other features) a real SID on it, ready to use on any MSX machine.
* In May 2015 Gianluca Ghettini developed SidBerry, an open source, open hardware board to interface a MOS 6581 SID chip to a RaspberryPi and play standard SID music files
* In 2016 Thibaut Varene published exSID, a USB audio device that can control a real 6581 and 8580 SID chip and natively playback most SID tunes.

=== Hardware reimplementations ===
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* In 2008 the HyperSID project was released. HyperSID is a [[VSTi]] which acts like a MIDI controller for HyperSID hardware unit (synthesizer based on SID chip) and developed by HyperSynth company.{{citation needed|date=February 2018}}
* The SwinSID is hardware emulation of the SID using an Atmel AVR processor, also featuring a real SID player based on the Atmel AVR processor.
* The V-SID 1.0 project (code name SID 6581D, 'D' for digital) from David {{sic|hide=y|Amoros}} was born in 2005. This project is a hardware emulation of the SID chip from the Bob Yannes's interview, datasheets. The V-SID 1.0 engine had been implemented in a [[FPGA]] EP1C12 Cyclone from ALTERA, on an ALTIUM development board, and emulates all the characteristics of the original SID, except the filter which is a digital version (IIR filter controlled by a CPU).
* The PhoenixSID 65X81 project (2006) aimed to faithfully create the SID sound using modern hardware. The workings of a SID chip were recreated on an [[FPGA]], based on interviews with the SID's creator, original datasheets, and comparisons with real SID chips. It was distinguished from similar attempts by its use of real analog circuitry instead of emulation for the legendary SID filter. However, the project was discontinued, because George Pantazopoulos, who was the head of this project, died on April 23, 2007, at the age of 29.
* The [[C64 Direct-to-TV]] emulates large portions the SID hardware, minus certain features such as (most notably) the filters. It reduces the entire C64 to a small circuit that fits into a joystick while sacrificing some compatibility.
* The SIDcog is a software SID emulator running on the [[Parallax Propeller]]. All three channels can be emulated on one of the Propeller's eight COG's.
* The ARMSID is a "plug & play" replacement of the MOS 6581 and MOS 8580 with analog inputs support.
* The FPGASID is a FPGA based SID replica providing high reproduction quality of the original device including all features such as the audio filters and the paddle registers. The device is a full featured stereo solution and can replace two SID chips in a single SID socket. Hardware base is an Altera MAX10 FPGA.