Three projects arguably delivered a complete microprocessor at about the same time, namely Intel's 4004, the Texas Instruments (TI) TMS 1000, and Garrett AiResearch's Central Air Data Computer (CADC).
Intel's 4004 is considered the first microprocesor. This first microprocessor cost in the thousands of dollars. The first known advertisement for the 4004 is dated back to November 1971; it appeared in Electronic News. The project that produced Intel's first known microprocessor originated in 1969, when Busicom, a Japanese calculator manufacturer, asked Intel to build a chip set for high-performance desktop calculators. Busicom's original design called for a dozen different logic and memory chips. Ted Hoff, the Intel engineer assigned to the project, believed the design was not cost effective. His solution was to simplify the design and produce a programmable processor capable of creating a set of complex special-purpose calculator chips. Together with Masatoshi Shima and Federico Faggin, later the founder of Zilog, Hoff came up with a four-chip design; a ROM for custom application programs, a RAM for processing data, an I/O device, and an unnamed 4-bit central processing unit which would become known as a "microprocessor."
The Smithsonian Institution says TI engineers Gary Boone and Michael Cochran succeeded in creating the first microcontroller (also called a microcomputer) in 1971. The result of their work was the TMS 1000 which went commercial in 1974. Ray Holt, a graduate of California Polytechnical University in 1968, began his computer design career with the F14 CADC.
The central air data computer was shrouded in secrecy for over 30 years from its creation (the year being 1968), it was not publicly known until 1998 at which time, at the request of Mr. Ray Holt, the US Navy allowed the documents into the public domain. Since then many debates have argued that this was, in fact, the first microprocessor. The scientific papers and literature published around 1971 reveal that the MP944 digital processor used for the F-14 Tomcat aircraft of the US Navy qualifies as the “first microprocessor”. Although interesting, it was not a single-chip processor, and was not general purpose – it was more like a set of parallel building blocks you could use to make a special-purpose DSP form. It indicates that today’s industry theme of converging DSP-microcontroller architectures was started in 1971. This convergence of DSP and microcontroller architectures is know as a Digital Signal Controller
In 1968, Garrett AiResearch, with designer Ray Holt and Steve Geller, were invited to produce a digital computer to compete with electromechanical systems then under development for the main flight control computer in the US Navy's new F-14 Tomcat fighter. The design was complete by 1970, and used a MOS-based chipset as the core CPU. The design was significantly (approximately 20 times) smaller and much more reliable than the mechanical systems it competed against, and was used in all of the early Tomcat models. This system contained a "a 20-bit, pipelined, parallel multi-microprocessor". However, the system was considered so advanced that the Navy refused to allow publication of the design until 1997. For this reason the CADC, and the MP944 chipset it used, are fairly unknown even today. (see First Microprocessor Chip Set.) TI developed the 4-bit TMS 1000, and stressed pre-programmed embedded applications, introducing a version called the TMS1802NC on September 17, 1971, which implemented a calculator on a chip. The Intel chip was the 4-bit 4004, released on November 15, 1971, developed by Federico Faggin and Ted Hoff. The manager of the design team was Leslie L. Vadász.
[The first microprocessor to make it into a home computer was the Intel 8080, a complete 8-bit computer on one chip, introduced in 1974. The first microprocessor to make a real splash in the market was the Intel 8088, introduced in 1979 and incorporated into the IBM PC (which first appeared around 1982). If you are familiar with the PC market and its history, you know that the PC market moved from the 8088 to the 80286 to the 80386 to the 80486 to the Pentium to the Pentium II to the Pentium III to the Pentium 4. All of these microprocessors are made by Intel and all of them are improvements on the basic design of the 8088. The Pentium 4 can execute any piece of code that ran on the original 8088, but it does it about 5,000 times faster!]
The following table helps you to understand the differences between the different processors that Intel has introduced over the years.
8-bit bus | ||||||
64-bit bus | ||||||
64-bit bus | ||||||
64-bit bus | ||||||
64-bit bus | ||||||
64-bit bus |
---->The date is the year that the processor was first introduced. Many processors are re-introduced at higher clock speeds for many years after the original release date.# Transistors is the number of transistors on the chip. You can see that the number of transistors on a single chip has risen steadily over the years.
----> Microns is the width, in microns, of the smallest wire on the chip. For comparison, a human hair is 100 microns thick. As the feature size on the chip goes down, the number of transistors rises.
----> Clock speed is the maximum rate that the chip can be clocked at. Clock speed will make more sense in the next section.
----> Data Width is the width of the ALU. An 8-bit ALU can add/subtract/multiply/etc. two 8-bit numbers, while a 32-bit ALU can manipulate 32-bit numbers. An 8-bit ALU would have to execute four instructions to add two 32-bit numbers, while a 32-bit ALU can do it in one instruction. In many cases, the external data bus is the same width as the ALU, but not always. The 8088 had a 16-bit ALU and an 8-bit bus, while the modern Pentiums fetch data 64 bits at a time for their 32-bit ALUs.
----> MIPS stands for "millions of instructions per second" and is a rough measure of the performance of a CPU. Modern CPUs can do so many different things that MIPS ratings lose a lot of their meaning, but you can get a general sense of the relative power of the CPUs from this column.
This is about as simple as a microprocessor gets. This microprocessor has:
- An address bus (that may be 8, 16 or 32 bits wide) that sends an address to memory
- A data bus (that may be 8, 16 or 32 bits wide) that can send data to memory or receive data from memory
- An RD (read) and WR (write) line to tell the memory whether it wants to set or get the addressed location
- A clock line that lets a clock pulse sequence the processor
- A reset line that resets the program counter to zero (or whatever) and restarts execution
General purpose
In April 1974, Intel introduced the 8-bit 8080, the first general-purpose microprocessor. With the ability to execute 290,000 instructions per second and 64K bytes of addressable memory, the 8080 was the first microprocessor with the speed, power, and efficiency to become a key tool for designers. Development labs set up by Hamilton/Avnet, Intel's first microprocessor distributor, showcased the 8080 and provided a broad customer base which contributed to its becoming the industry standard. A key factor in the 8080's success was its role in the introduction in January 1975 of the MITS Altair 8800, the first personal computer. It used the powerful 8080 microprocessor and established the precedent that personal computers must be easy to expand. With its increased sophistication, expandability, and an incredibly low price of $395, the Altair 8800 proved the viability of home computers.
TI filed for the patent on the microprocessor. Gary Boone was awarded U.S. Patent 3,757,306 for the single-chip microprocessor architecture on September 4, 1973. It may never be known which company actually had the first working microprocessor running on the lab bench. In both 1971 and 1976, Intel and TI entered into broad patent cross-licensing agreements, with Intel paying royalties to TI for the microprocessor patent. A nice history of these events is contained in court documentation from a legal dispute between Cyrix and Intel, with TI as intervenor and owner of the microprocessor patent.
Interestingly, a third party (Gilbert Hyatt) was awarded a patent which might cover the "microprocessor". See a webpage claiming an invention pre-dating both TI and Intel, describing a "microcontroller". According to a rebuttal and a commentary, the patent was later invalidated, but not before substantial royalties were paid out.
A computer-on-a-chip is a variation of a microprocessor which combines the microprocessor core (CPU), some memory, and I/O (input/output) lines, all on one chip.It is also called as micro-controller. The computer-on-a-chip patent, called the "microcomputer patent" at the time, U.S. Patent 4,074,351, was awarded to Gary Boone and Michael J. Cochran of TI. Aside from this patent, the standard meaning of microcomputer is a computer using one or more microprocessors as its CPU(s), while the concept defined in the patent is perhaps more akin to a microcontroller.
According to A History of Modern Computing, (MIT Press), pp. 220–21, Intel entered into a contract with Computer Terminals Corporation, later called Datapoint, of San Antonio TX, for a chip for a terminal they were designing. Datapoint later decided not to use the chip, and Intel marketed it as the 8008 in April, 1972. This was the world's first 8-bit microprocessor. It was the basis for the famous "Mark-8" computer kit advertised in the magazine Radio-Electronics in 1974. The 8008 and its successor, the world-famous 8080, opened up the microprocessor component marketplace.
Notable 8-bit designs
The 4004 was later followed in 1972 by the 8008, the world's first 8-bit microprocessor. These processors are the precursors to the very successful Intel 8080 (1974), Zilog Z80 (1976), and derivative Intel 8-bit processors. The competing Motorola 6800 was released August 1974 and the similar MOS Technology 6502 in 1975 (designed largely by the same people). The 6502 rivaled the Z80 in popularity during the 1980s.
A low overall cost, small packaging, simple computer bus requirements, and sometimes circuitry otherwise provided by external hardware (the Z80 had a built in memory refresh) allowed the home computer "revolution" to accelerate sharply in the early 1980s, eventually delivering such inexpensive machines as the Sinclair ZX-81, which sold for US$99.
16-bit designs
The first multi-chip 16-bit microprocessor was the National Semiconductor IMP-16, introduced in early 1973. An 8-bit version of the chipset was introduced in 1974 as the IMP-8. During the same year, National introduced the first 16-bit single-chip microprocessor, the National Semiconductor PACE, which was later followed by an NMOS version, the INS8900.
Other early multi-chip 16-bit microprocessors include one used by Digital Equipment Corporation (DEC) in the LSI-11 OEM board set and the packaged PDP 11/03 minicomputer, and the Fairchild Semiconductor MicroFlame 9440, both of which were introduced in the 1975 to 1976 timeframe.
The first single-chip 16-bit microprocessor was TI's TMS 9900, which was also compatible with their TI-990 line of minicomputers. The 9900 was used in the TI 990/4 minicomputer, the TI-99/4A home computer, and the TM990 line of OEM microcomputer boards. The chip was packaged in a large ceramic 64-pin DIP package, while most 8-bit microprocessors such as the Intel 8080 used the more common, smaller, and less expensive plastic 40-pin DIP. A follow-on chip, the TMS 9980, was designed to compete with the Intel 8080, had the full TI 990 16-bit instruction set, used a plastic 40-pin package, moved data 8 bits at a time, but could only address 16 KB. A third chip, the TMS 9995, was a new design. The family later expanded to include the 99105 and 99110.
32-bit designs
16-bit designs were in the markets only briefly when full 32-bit implementations started to appear.
The most significant of the 32-bit designs is the MC68000, introduced in 1979. The 68K, as it was widely known, had 32-bit registers but used 16-bit internal data paths, and a 16-bit external data bus to reduce pin count, and supported only 24-bit addresses. Motorola generally described it as a 16-bit processor, though it clearly has 32-bit architecture. The combination of high performance, large (16 megabytes (2^24)) memory space and fairly low costs made it the most popular CPU design of its class. The Apple Lisa and Macintosh designs made use of the 68000, as did a host of other designs in the mid-1980s, including the Atari ST and Commodore 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 Bell Labs BELLMAC-32A, with first samples in 1980, and general production in 1982 (See this bibliographic reference and this general reference). After the 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 supermicrocomputer; in the "Companion", the world's first 32-bit laptop computer; and in "Alexander", the world's first book-sized supermicrocomputer, featuring ROM-pack memory cartridges similar to today's gaming consoles. All these systems ran the UNIX System V operating system.
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 object-oriented architecture, but poor performance compared to other competing architectures such as the Motorola 68000.
64-bit designs in personal computers
While 64-bit microprocessor designs have been in use in several markets since the early 1990s, the early 2000s saw the introduction of 64-bit microchips targeted at the PC market.
With AMD's introduction of a 64-bit architecture backwards-compatible with x86, x86-64 (now called AMD64), in September 2003, followed by Intel's near fully compatible 64-bit extensions (first called IA-32e or EM64T, later renamed Intel 64), the 64-bit desktop era began. Both versions can run 32-bit legacy applications without any performance penalty as well as new 64-bit software. With operating systems Windows XP x64, Windows Vista x64, Linux, BSD and Mac OS X that run 64-bit native, the software is also geared to fully utilize the capabilities of such processors. The move to 64 bits is more than just an increase in register size from the IA-32 as it also doubles the number of general-purpose registers.
The move to 64 bits by PowerPC processors had been intended since the processors' design in the early 90s and was not a major cause of incompatibility. Existing integer registers are extended as are all related data pathways, but, as was the case with IA-32, both floating point and vector units had been operating at or above 64 bits for several years. Unlike what happened when IA-32 was extended to x86-64, no new general purpose registers were added in 64-bit PowerPC, so any performance gained when using the 64-bit mode for applications making no use of the larger address space is minimal.
SEE :
INTEL 8085 Mp
INTEL 8086 MP
