Editing Microprocessor (section)

===32-bit designs===
[[File:80486DX2 200x.png|thumb|Upper interconnect layers on an [[Intel 80486]]DX2 die]]

16-bit designs had only been on the market briefly when [[32-bit]] implementations started to appear.

The most significant of the 32-bit designs is the [[Motorola MC68000]], introduced in 1979. The 68k, as it was widely known, had 32-bit registers in its programming model but used 16-bit internal data paths, three 16-bit Arithmetic Logic Units, and a 16-bit external data bus (to reduce pin count), and externally supported only 24-bit addresses (internally it worked with full 32&nbsp;bit addresses). In [[PC-based IBM-compatible mainframes]] the MC68000 internal microcode was modified to emulate the 32-bit System/370 IBM mainframe.<ref>{{cite web |url=https://priorart.ip.com/IPCOM/000059679 |title=Implementation of IBM System 370 Via Co-Microprocessors/The Co-Processor Interface on priorart.ip.com |publisher=priorart.ip.com |date=1986-01-01 |access-date=2020-07-23 |archive-date=11 December 2015 |archive-url=https://web.archive.org/web/20151211060121/http://priorart.ip.com/IPCOM/000059679 |url-status=live }}</ref> Motorola generally described it as a 16-bit processor. The combination of high performance, large (16&nbsp;[[megabyte]]s or 2<sup>24</sup>&nbsp;bytes) memory space and fairly low cost made it the most popular [[CPU design]] of its class. The [[Apple Lisa]] and [[Macintosh 128K|Macintosh]] designs made use of the 68000, as did other designs in the mid-1980s, including the [[Atari ST]] and [[Amiga]].

The world's first single-chip fully 32-bit microprocessor, with 32-bit data paths, 32-bit buses, and 32-bit addresses, was the [[AT&T Corporation|AT&T]] [[Bell Labs]] [[Bellmac 32|BELLMAC-32A]], with first samples in 1980, and general production in 1982.<ref>{{cite web|title=Shoji, M. Bibliography|url=http://cm.bell-labs.com/cm/cs/bib/shoji.bib|date=7 October 1998<!-- page info -->|publisher=Bell Laboratories|access-date=2009-12-23|url-status=dead|archive-url=https://web.archive.org/web/20081016070217/http://cm.bell-labs.com/cm/cs/bib/shoji.bib|archive-date=16 October 2008}}</ref><ref>{{cite web|title=Timeline: 1982–1984|website=Physical Sciences & Communications at Bell Labs|publisher=Bell Labs, Alcatel-Lucent|url=http://www.bell-labs.com/org/physicalsciences/timeline/span23.html |archive-url=https://web.archive.org/web/20110514025934/http://www.bell-labs.com/org/physicalsciences/timeline/span23.html |archive-date=2011-05-14 |date=17 January 2001 |access-date=2009-12-23}}</ref> After the [[Bell System divestiture|divestiture of AT&T]] in 1984, it was renamed the WE 32000 (WE for [[Western Electric]]), and had two follow-on generations, the WE 32100 and WE 32200. These microprocessors were used in the AT&T 3B5 and 3B15 minicomputers; in the 3B2, the world's first desktop super microcomputer; in the "Companion", the world's first 32-bit [[laptop]] computer; and in "Alexander", the world's first book-sized super microcomputer, featuring ROM-pack memory cartridges similar to today's gaming consoles. All these systems ran the [[UNIX System V]] operating system.

The first commercial, single chip, fully 32-bit microprocessor available on the market was the [[HP FOCUS]].

Intel's first 32-bit microprocessor was the [[iAPX 432]], which was introduced in 1981, but was not a commercial success. It had an advanced [[Capability-based security|capability-based]] [[Object (computer science)|object-oriented]] architecture, but poor performance compared to contemporary architectures such as Intel's own 80286 (introduced 1982), which was almost four times as fast on typical benchmark tests. However, the results for the iAPX432 was partly due to a rushed and therefore suboptimal [[Ada (programming language)|Ada]] [[compiler]].{{citation needed|date=April 2011}}

Motorola's success with the 68000 led to the [[MC68010]], which added [[virtual memory]] support. The [[MC68020]], introduced in 1984 added full 32-bit data and address buses. The 68020 became hugely popular in the [[Unix]] supermicrocomputer market, and many small companies (e.g., [[Altos Computer Systems|Altos]], [[UNOS (operating system)|Charles River Data Systems]], [[Cromemco]]) produced desktop-size systems. The [[MC68030]] was introduced next, improving upon the previous design by integrating the MMU into the chip. The continued success led to the [[MC68040]], which included an [[floating-point unit|FPU]] for better math performance. The 68050 failed to achieve its performance goals and was not released, and the follow-up [[Motorola 68060|MC68060]] was released into a market saturated by much faster RISC designs. The 68k family faded from use in the early 1990s.

Other large companies designed the 68020 and follow-ons into embedded equipment. At one point, there were more 68020s in embedded equipment than there were [[Intel]] Pentiums in PCs.<ref>{{cite web|title=MCore: Does Motorola Need Another Processor Family?|last=Turley|first=Jim|website=Embedded Systems Design|publisher=TechInsights (United Business Media)|url=http://www.embedded.com/98/9807sr.htm|date=July 1998|archive-url=https://web.archive.org/web/19980702003323/http://www.embedded.com/98/9807sr.htm |archive-date=1998-07-02|access-date=2009-12-23}}</ref> The [[ColdFire]] processor cores are derivatives of the 68020.

During this time (early to mid-1980s), [[National Semiconductor]] introduced a very similar 16-bit pinout, 32-bit internal microprocessor called the NS 16032 (later renamed 32016), the full 32-bit version named the [[NS320xx|NS 32032]]. Later, National Semiconductor produced the [[NS320xx|NS 32132]], which allowed two CPUs to reside on the same memory bus with built in arbitration. The NS32016/32 outperformed the MC68000/10, but the NS32332—which arrived at approximately the same time as the MC68020—did not have enough performance. The third generation chip, the NS32532, was different. It had about double the performance of the MC68030, which was released around the same time. The appearance of RISC processors like the AM29000 and MC88000 (now both dead) influenced the architecture of the final core, the NS32764. Technically advanced—with a superscalar RISC core, 64-bit bus, and internally overclocked—it could still execute Series 32000 instructions through real-time translation.

When National Semiconductor decided to leave the Unix market, the chip was redesigned into the Swordfish Embedded processor with a set of on-chip peripherals. The chip turned out to be too expensive for the [[laser printer]] market and was killed. The design team went to Intel and there designed the Pentium processor, which is very similar to the NS32764 core internally. The big success of the Series 32000 was in the laser printer market, where the NS32CG16 with microcoded BitBlt instructions had very good price/performance and was adopted by large companies like Canon. By the mid-1980s, [[Sequent Computer Systems|Sequent]] introduced the first SMP server-class computer using the NS 32032. This was one of the design's few wins, and it disappeared in the late 1980s. The [[MIPS architecture|MIPS]] [[R2000 (microprocessor)|R2000]] (1984) and [[R3000]] (1989) were highly successful 32-bit RISC microprocessors. They were used in high-end workstations and servers by [[Silicon Graphics|SGI]], among others. Other designs included the [[Zilog Z80000]], which arrived too late to market to stand a chance and disappeared quickly.

The [[ARM architecture family|ARM]] first appeared in 1985.<ref>
{{cite journal
| title = Speciation through entrepreneurial spin-off: The Acorn-ARM story
| journal = Research Policy
| date = March 2008
| first = Elizabeth
| last = Garnsey
|author2= Lorenzoni, Gianni|author3= Ferriani, Simone
| volume = 37
| issue = 2
| pages = 210–224
| url = http://www2.sa.unibo.it/~simone.ferriani/Download/Speciation%20through%20Entrepreneurial%20Spin-off.pdf
| access-date = 2011-06-02
| quote = [...] the first silicon was run on April 26th 1985.
| doi=10.1016/j.respol.2007.11.006| s2cid = 73520408
}}
</ref> This is a [[RISC]] processor design, which has since come to dominate the 32-bit [[embedded systems]] processor space due in large part to its power efficiency, its licensing model, and its wide selection of system development tools. Semiconductor manufacturers generally license cores and integrate them into their own [[system on a chip]] products; only a few such vendors such as Apple are licensed to modify the ARM cores or create their own. Most [[cell phones]] include an ARM processor, as do a wide variety of other products. There are microcontroller-oriented ARM cores without virtual memory support, as well as [[symmetric multiprocessor]] (SMP) applications processors with virtual memory.

From 1993 to 2003, the 32-bit [[x86]] architectures became increasingly dominant in [[desktop computer|desktop]], [[laptop]], and server markets, and these microprocessors became faster and more capable. Intel had licensed early versions of the architecture to other companies, but declined to license the Pentium, so [[AMD]] and [[Cyrix]] built later versions of the architecture based on their own designs. During this span, these processors increased in complexity (transistor count) and capability (instructions/second) by at least three orders of magnitude. Intel's Pentium line is probably the most famous and recognizable 32-bit processor model, at least with the public at broad.