Symbolics, Inc. was a
computer manufacturer headquartered in
Cambridge, Massachusetts, and later in
Concord, Massachusetts, with manufacturing facilities in
Chatsworth, Los Angeles. Robert P. Adams (an MIT graduate) was Symbolics’ first President and co-founder along with Russell Noftsker, and in fact, the name “Symbolics” was coined by Robert Adams while the company was initially being formed in his home in Santa Monica, California. Its first CEO, chairman, and co-founder was
Russell Noftsker. Symbolics designed and manufactured a line of
Lisp machines, single-user computers optimized to run the
programming language Lisp. Symbolics also made significant advances in software technology, and offered one of the premier software development environments of the 1980s and 1990s, now sold commercially as
Open Genera for
Tru64 UNIX on the
Hewlett-Packard (HP)
Alpha. Symbolics was a spinoff from the
MIT AI Lab, one of two companies to be founded by AI Lab staffers and associated
hackers for the purpose of manufacturing Lisp machines. The other was
Lisp Machines, Inc., although Symbolics attracted most of the hackers, and more funding. Symbolics' initial product, the LM-2, introduced in 1981, was a repackaged version of the MIT CADR
Lisp machine design. The
operating system and software development environment, over 500,000 lines, was written in Lisp from the
microcode up, based on MIT's
Lisp Machine Lisp. The software bundle was later renamed
ZetaLisp, to distinguish the Symbolics' product from other vendors who had also licensed the MIT software. Symbolics'
Zmacs text editor, a variant of
Emacs, was implemented in a text-processing package named
ZWEI, an acronym for
Zwei was Eine initially, with
Eine being an acronym for
Eine Is Not Emacs. Both are
recursive acronyms and puns on the German words for
one (
eins,
eine) and
two (
zwei). The Lisp Machine system software was then copyrighted by MIT, and was licensed to both Symbolics and LMI. Until 1981, Symbolics shared all its copyrighted enhancements to the
source code with MIT and kept it on an MIT server. According to
Richard Stallman, Symbolics engaged in a business tactic in which it forced MIT to make all Symbolics' copyrighted fixes and improvements to the Lisp Machine OS available only to Symbolics (and MIT but not to Symbolics competitors), and thereby choke off its competitor LMI, which at that time had insufficient resources to independently maintain or develop the OS and environment. Symbolics felt that it no longer had sufficient control over its product. At that point, Symbolics began using its own copy of the software, located on its company servers, while Stallman says that Symbolics did that to prevent its Lisp improvements from flowing to Lisp Machines, Inc. From that base, Symbolics made extensive improvements to every part of the software, and continued to deliver almost all the source code to its customers (including MIT). However, the policy prohibited MIT staff from distributing the Symbolics version of the software to others. With the end of open collaboration came the end of the MIT hacker community. As a reaction to this, Stallman initiated the
GNU project to make a new community. Eventually,
Copyleft and the
GNU General Public License would ensure that a hacker's software could remain
free software. In this way, Symbolics played a key, albeit adversarial, role in instigating the
free software movement.
The 3600 series 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
cache for the top of the
control stack; the rest were used by the
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, which was unique. The original 3600 processor was a
microprogrammed design like the CADR, and was built on several large circuit boards from standard
TTL integrated circuits, 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 MHz. Many Lisp primitives could be executed in a single
clock cycle. Disk
input/output (I/O) was handled by
multitasking inside of the
microcode level. A
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 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 , and later , disk drives that could hold hundreds of
megabytes 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. 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, 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. 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 by Izware LLC, and continues to be used in major motion pictures (most famously in New Line Cinema's
The Lord of the Rings), video games, and military simulations. 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.
Ivory and Open Genera In the late 1980s (2 years later than planned), the Ivory family of single-chip Lisp Machine processors superseded the G-Machine 3650, 3620, and 3630 systems. The Ivory 390k transistor VLSI implementation designed in Symbolics Common Lisp using NS, a custom Symbolics Hardware Design Language (HDL), addressed a 40-bit word (8 bits tag, 32 bits data/address). Since it only addressed full words and not bytes or half-words, this allowed addressing of 4
Gigawords (GW) or 16
gigabytes (GB) of memory; the increase in
address space reflected the growth of programs and data as semiconductor memory and disk space became cheaper. The Ivory processor had 8 bits of ECC attached to each word, so each word fetched from external memory to the chip was actually 48 bits wide. Each Ivory instruction was 18 bits wide and two instructions plus a 2-bit CDR code and 2-bit Data Type were in each instruction word fetched from memory. Fetching two instruction words at a time from memory enhanced the Ivory's performance. Unlike the 3600's
microprogrammed architecture, the Ivory instruction set was still microcoded, but was stored in a 1200 × 180-bit ROM inside the Ivory chip. The initial Ivory processors were fabricated by
VLSI Technology Inc in
San Jose, California, on a 2
μm CMOS process, with later generations fabricated by
Hewlett-Packard in
Corvallis, Oregon, on 1.25 μm and 1 μm CMOS processes. The Ivory had a stack architecture and operated a 4-stage pipeline: Fetch, Decode, Execute and Write Back. Ivory processors were marketed in stand-alone Lisp Machines (the XL400, XL1200, and XL1201), headless Lisp Machines (NXP1000), and on add-in cards for
Sun Microsystems (UX400, UX1200) and
Apple Macintosh (MacIvory I, II, III) computers. The Lisp Machines with Ivory processors operated at speeds that were between two and six times faster than a 3600 depending on the model and the revision of the Ivory chip. The Ivory
instruction set was later emulated in software for
microprocessors implementing the 64-bit
Alpha architecture. The "Virtual Lisp Machine"
emulator, combined with the
operating system and software development environment from the XL machines, is sold as Open Genera.
Sunstone Sunstone was a processor similar to a
reduced instruction set computer (RISC), that was to be released shortly after the Ivory. It was designed by Ron Lebel's group at the Symbolics Westwood office. However, the project was canceled the day it was supposed to tape out.
Endgame As quickly as the commercial AI boom of the mid-1980s had propelled Symbolics to success, the
AI Winter of the late 1980s and early 1990s, combined with the slowdown of the
Ronald Reagan administration's
Strategic Defense Initiative, popularly termed
Star Wars,
missile defense program, for which the
Defense Advanced Research Projects Agency (
DARPA) had invested heavily in AI solutions, severely damaged Symbolics. An internal war between Noftsker and the CEO the board had hired in 1986, Brian Sear, over whether to follow Sun's suggested lead and focus on selling its software, or to re-emphasize its superior hardware, and the ensuing lack of focus when both Noftsker and Sear were fired from the company caused sales to plummet. This, combined with some ill-advised real estate deals by company management during the boom years (they had entered into large long-term lease obligations in California), drove Symbolics into
bankruptcy. Rapid evolution in
mass market microprocessor technology (the
PC revolution), advances in Lisp
compiler technology, and the economics of manufacturing custom
microprocessors severely diminished the commercial advantages of purpose-built Lisp machines. By 1995, the Lisp machine era had ended, and with it Symbolics' hopes for success. Symbolics continued as an enterprise with very limited revenues, supported mainly by service contracts on the remaining MacIvory, UX-1200, UX-1201, and other machines still used by commercial customers. Symbolics also sold Virtual Lisp Machine (VLM) software for DEC, Compaq, and HP Alpha-based workstations (
AlphaStation) and servers (
AlphaServer), refurbished MacIvory IIs, and Symbolics keyboards. In July 2005, Symbolics closed its
Chatsworth, California, maintenance facility. The reclusive owner of the company, Andrew Topping, died the same year. The current legal status of Symbolics software is uncertain. An assortment of Symbolics hardware was still available for purchase . In 2011, the
United States Department of Defense awarded Symbolics a 5 year contract for maintenance work, ending in September 2016.
First .com domain On 15 March 1985, symbolics.com became
the first (and currently, since it is still registered, the oldest) registered domain of the Internet. The symbolics.com domain was purchased by Napkin.com in 2009. ==Networking==