Editing Symbolics (section)

===The 3600 series===
[[File:Symbolics3640 Modified.JPG|thumb|Symbolics 3640]]
[[File:Symbolics-3600-on.jpg|thumb|Symbolics 3600 Front Panel]]
[[File:Symbolics-3670-boards.jpg|thumb|Symbolics Boards]]
In 1983, a year later than planned, Symbolics introduced the 3600 family of Lisp machines. Code-named the "L-machine" internally, the 3600 family was an innovative new design, inspired by the CADR architecture but sharing few of its implementation details. The main processor had a 36-[[bit]] [[word]] (divided up as 4 or 8 bits of tags, and 32 bits of data or 28 bits of memory address). Memory words were 44 bits, the additional 8 bits being used for [[error-correcting code]] (ECC). The [[instruction set]] was that of a [[stack machine]]. The 3600 architecture provided 4,096 hardware registers, of which half were used as a [[CPU cache|cache]] for the top of the [[control stack]]; the rest were used by the [[Microprogram|microcode]] and time-critical routines of the [[operating system]] and Lisp run-time environment. Hardware support was provided for [[virtual memory]], which was common for machines in its class, and for [[Garbage collection (computer science)|garbage collection]], which was unique.

The original 3600 processor was a [[microprogram]]med design like the CADR, and was built on several large circuit boards from standard [[Transistor-transistor logic|TTL]] [[integrated circuit]]s, both features being common for commercial computers in its class at the time. [[Central processing unit]] (CPU) [[clock speed]] varied depending on which instruction was being executed, but was typically around 5&nbsp;MHz. Many Lisp primitives could be executed in a single [[clock cycle]]. Disk [[input/output]] (I/O) was handled by [[computer multitasking|multitasking]] at the [[Microprogram|microcode]] level. A [[Motorola 68000 series|68000 processor]] (termed the ''front-end processor'', (FEP)) started the main computer up, and handled the slower peripherals during normal operation. An [[Ethernet]] interface was standard equipment, replacing the [[Chaosnet]] interface of the LM-2.

The 3600 was roughly the size of a household refrigerator. This was partly due to the size of the processor (the cards were widely spaced to allow [[wire-wrap]] prototype cards to fit without interference) and partly due to the size of disk drive technology in the early 1980s. At the 3600's introduction, the smallest disk that could support the [[ZetaLisp]] software was {{convert|14|in|mm}} wide (most 3600s shipped with the 10½-inch [[Fujitsu Eagle]]). The 3670 and 3675 were slightly shorter in height, but were essentially the same machine packed a little tighter. The advent of {{convert|8|in|mm}}, and later {{convert|5+1/4|in|mm}}, disk drives that could hold hundreds of [[megabyte]]s led to the introduction of the 3640 and 3645, which were roughly the size of a two-drawer file cabinet.

Later versions of the 3600 architecture were implemented on custom integrated circuits, reducing the five cards of the original processor design to two, at a large manufacturing cost savings and with performance slightly better than the old design. The 3650, first of the ''G machines'', as they were known within the company, was housed in a cabinet derived from the 3640s. Denser memory and smaller disk drives enabled the introduction of the 3620, about the size of a modern full-size tower PC. The 3630 was a ''fat 3620'' with room for more memory and video interface cards. The 3610 was a lower priced variant of the 3620, essentially identical in every way except that it was licensed for application deployment rather than general development.

{| class="wikitable plainrowheaders"
|+ 36xx machines
! scope="col" | Model
! scope="col" | Year
! scope="col" | Description
|-
! scope="row" | 3600
| 1983 || Workstation
|-
! scope="row" | 3670
| 1984 || Workstation
|-
! scope="row" | 3640
| 1984 || Workstation
|-
! scope="row" | 3675
| 1985 || Workstation
|-
! scope="row" | 3645
| 1985 || Workstation
|-
! scope="row" | 3610
| 1986 || Workstation
|-
! scope="row" | 3620
| 1986 || Workstation
|-
! scope="row" | 3650
| 1986 || Workstation
|}

[[File:Symbolics-keyboard.jpg|thumb|Symbolics Keyboard]]

The various models of the 3600 family were popular for [[artificial intelligence]] (AI) research and commercial applications throughout the 1980s. The AI commercialization boom of the 1980s led directly to Symbolics' success during the decade. Symbolics computers were widely believed to be the best platform available for developing AI software. The LM-2 used a Symbolics-branded version of the complex [[space-cadet keyboard]],<ref>{{cite web
|title=Symbolics LM-2 Symbol Processing System
|author=<!-- Unstated -->
|url=http://bitsavers.trailing-edge.com/pdf/symbolics/brochures/LM-2.pdf |website=Bitsavers}}</ref> while later models used a simplified version (at right), known simply as the ''{{visible anchor|Symbolics keyboard}}''.<ref>{{cite web
|title=Symbolics 3600 Symbol Processing System
|author=<!-- Unstated -->
|url=http://bitsavers.trailing-edge.com/pdf/symbolics/brochures/3600_Jul83.pdf |website=Bitsavers}}</ref> The Symbolics keyboard featured the many [[modifier key]]s used in Zmacs, notably Control/Meta/Super/Hyper in a block, but did not feature the complex symbol set of the space-cadet keyboard.

Also contributing to the 3600 series' success was a line of [[bit-mapped graphics]] color video interfaces, combined with extremely powerful animation software. Symbolics' Graphics Division, headquartered in [[Westwood, Los Angeles]], California, near to the major Hollywood movie and television studios, made its S-Render and S-Paint software into industry leaders in the animation business and its 24 fps lock displays were featured in Star Trek movies.<ref name="Kalman Reti">
[https://www.youtube.com/@lispwizard/videos Kalman Reti] :  [https://www.youtube.com/watch?v=jACcgLfyiyM<!--  https://web.archive.org/web/20230529052554/http://people.csail.mit.edu/reti/SymbolicsTalk28June2012.m4v   https://docs.google.com/file/d/0Bw4Wz8Ir0pl1cmNRaHYwdU1wdXM/    -->  History of Symbolics Lisp machines] (including a demo of Brad Parker's emulator port) – The Last Symbolics Developer, at [[MIT]] at a meeting of the Boston Lisp group, 28 June 2012 @  [[YouTube]]</ref><ref>{{cite web |url=https://fare.livejournal.com/168016.html |title=Boston Lisp Meeting Thursday 2012-06-28 Kalman Reti on Symbolics Lisp Machines |website=LiveJournal |date=19 June 2012 |access-date=27 May 2024}}</ref><ref>{{cite web |archive-url=https://web.archive.org/web/20230529052554/http://www.loper-os.org/?p=932 |archive-date=29 May 2023 |url=http://www.loper-os.org/?p=932 |url-status=live |title=Kalman Reti, the Last Symbolics Developer, Speaks of Lisp Machines |date=5 September 2012 |access-date=27 May 2024}}</ref><ref>{{cite web |archive-url=https://web.archive.org/web/20210422103134/http://www.ai.mit.edu/projects/tuesday-group-as-of-02mar03/ |archive-date=22 April 2021 |url=http://www.ai.mit.edu/projects/tuesday-group-as-of-02mar03/ |url-status=live |access-date=27 May 2024 |title=The Tuesday Group |website=ai.mit.edu}}</ref><ref>{{cite web |url=https://www.theregister.com/2023/12/25/the_war_of_the_workstations/ |title=War of the workstations: How the lowest bidders shaped today's tech landscape |date=25 December 2023 |access-date=27 May 2024 |first=Liam |last=Proven |website=The Register}}</ref>

Symbolics developed the first workstations able to process [[high-definition television]] (HDTV) quality video, which enjoyed a popular following in Japan. A 3600, with the standard black-and-white monitor, made a cameo appearance in the movie ''[[Real Genius]]''. The company was also referenced in Michael Crichton's novel [[Jurassic Park (novel)|''Jurassic Park'']].

Symbolics' Graphics Division was sold to Nichimen Trading Company in the early 1990s, and the S-Graphics software suite (S-Paint, S-Geometry, S-Dynamics, S-Render) ported to Franz Allegro Common Lisp on [[Silicon Graphics]] (SGI) and PC computers running [[Windows NT]]. Today it is sold as [[Mirai (software)|Mirai]] by Izware LLC, and continues to be used in major motion pictures (most famously in New Line Cinema's ''[[The Lord of the Rings (film series)|The Lord of the Rings]]''), video games, and military simulations.

[[File:Symbolics-3600-ports.jpg|thumb|3600 ports, with Connection Machine interface]]
Symbolics' 3600-series computers were also used as the first front end ''controller'' computers for the [[Connection Machine]] massively parallel computers manufactured by [[Thinking Machines Corporation]], another MIT spinoff based in Cambridge, Massachusetts. The Connection Machine ran a parallel variant of Lisp and, initially, was used primarily by the AI community, so the Symbolics Lisp machine was a particularly good fit as a front-end machine.

For a long time, the operating system didn't have a name, but was finally named ''Genera'' around 1984. The system included several advanced dialects of Lisp. Its heritage was [[Maclisp]] on the PDP-10, but it included more data types, and multiple-inheritance [[object-oriented programming]] features. This Lisp dialect was called [[Lisp Machine Lisp]] at MIT. Symbolics used the name ZetaLisp. Symbolics later wrote new software in ''Symbolics Common Lisp'', its version of the [[Common Lisp]] standard.