A microprocessor is a computer processor for which the data processing logic and control is included on a single integrated circuit (IC), or a small number of ICs. The microprocessor contains the arithmetic, logic, and control circuitry required to perform the functions of a computer's central processing unit (CPU). The IC is capable of interpreting and executing program instructions and performing arithmetic operations. The microprocessor is a multipurpose, clock-driven, register-based, digital integrated circuit that accepts binary data as input, processes it according to instructions stored in its memory, and provides results as output. Microprocessors contain both combinational logic and sequential digital logic, and operate on numbers and symbols represented in the binary number system.
A minicomputer, or colloquially mini, is a type of smaller general-purpose computer developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, The New York Times suggested a consensus definition of a minicomputer as a machine costing less than US$25,000, with an input-output device such as a teleprinter and at least four thousand words of memory, that is capable of running programs in a higher level language, such as Fortran or BASIC.
The PDP–11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the late 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC's most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer.
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive. Many microcomputers are also personal computers. An early use of the term "personal computer" in 1962 predates microprocessor-based designs. (See "Personal Computer: Computers at Companies" reference below). A "microcomputer" used as an embedded control system may have no human-readable input and output devices. "Personal computer" may be used generically or may denote an IBM PC compatible machine.
The LINC is a 12-bit, 2048-word transistorized computer. The LINC is considered by some to be the first minicomputer and a forerunner to the personal computer. Originally named the Linc, suggesting the project's origins at MIT's Lincoln Laboratory, it was renamed LINC after the project moved from the Lincoln Laboratory. The LINC was designed by Wesley A. Clark and Charles Molnar.
The history of computing hardware starting at 1960 is marked by the conversion from vacuum tube to solid-state devices such as transistors and then integrated circuit (IC) chips. Around 1953 to 1959, discrete transistors started being considered sufficiently reliable and economical that they made further vacuum tube computers uncompetitive. Metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology subsequently led to the development of semiconductor memory in the mid-to-late 1960s and then the microprocessor in the early 1970s. This led to primary computer memory moving away from magnetic-core memory devices to solid-state static and dynamic semiconductor memory, which greatly reduced the cost, size, and power consumption of computers. These advances led to the miniaturized personal computer (PC) in the 1970s, starting with home computers and desktop computers, followed by laptops and then mobile computers over the next several decades.
4-bit computing is the use of computer architectures in which integers and other data units are 4 bits wide. 4-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers or data buses of that size. A group of four bits is also called a nibble and has 24 = 16 possible values, with a range of 0 to 15.
The HP 2100 is a series of 16-bit minicomputers that were produced by Hewlett-Packard (HP) from the mid-1960s to early 1990s. Tens of thousands of machines in the series were sold over its twenty-five year lifetime, making HP the fourth largest minicomputer vendor during the 1970s.
Modcomp, Inc., originally Modular Computer Systems, was a small minicomputer vendor that specialized in real-time applications. They were founded in 1970 in Fort Lauderdale, Florida. In the 1970s and 1980s, they produced a line of 16- and 32-bit mini-computers. Through the 1980s, Modcomp lost market share as more powerful micro-computers became popular, and Digital Equipment Corporation's VAX and Alpha systems continued to grow. The company successfully survives today as a systems integrator operating as CSPi Technology Solutions headquartered in Deerfield Beach, Florida.
Am2900 is a family of integrated circuits (ICs) created in 1975 by Advanced Micro Devices (AMD). They were constructed with bipolar devices, in a bit-slice topology, and were designed to be used as modular components each representing a different aspect of a computer control unit (CCU). By using the bit slicing technique, the Am2900 family was able to implement a CCU with data, addresses, and instructions to be any multiple of 4 bits by multiplying the number of ICs. One major problem with this modular technique was that it required a larger number of ICs to implement what could be done on a single CPU IC. The Am2901 chip included an arithmetic logic unit (ALU) and 16 4-bit processor register slices, and was the "core" of the series. It could count using 4 bits and implement binary operations as well as various bit-shifting operations. The Am2909 was a 4-bit-slice address sequencer that could generate 4-bit addresses on a single chip, and by using n of them, it was able to generate 4n-bit addresses. It had a stack that could store a microprogram counter up to 4 nest levels, as well as a stack pointer.
Systems Engineering Laboratories was a manufacturer of minicomputers in Fort Lauderdale, Florida. It was one of the first 32-bit realtime computer system manufacturers. Realtime computers are used for process control and monitoring.
Varian Data Machines was a division of Varian Associates which sold minicomputers. It entered the market in 1967 through acquisition of Decision Control Inc. (DCI) in Newport Beach, California. It met stiff competition and was bought by Sperry Corporation in June 1977 who merged it into their Sperry UNIVAC division as the Sperry UNIVAC Minicomputer Operation.
The Honeywell 316 was a popular 16-bit minicomputer built by Honeywell starting in 1969. It is part of the Series 16, which includes the Models 116, 316 (1969), 416 (1966), 516 (1966) and DDP-716 (1969). They were commonly used for data acquisition and control, remote message concentration, clinical laboratory systems, Remote Job Entry and time-sharing. The Series-16 computers are all based on the DDP-116 designed by Gardner Hendrie at Computer Control Company, Inc. (3C) in 1964.
Interdata, Inc., was a computer company, founded in 1966 by a former Electronic Associates engineer, Daniel Sinnott, and was based in Oceanport, New Jersey. The company produced a line of 16- and 32-bit minicomputers that were loosely based on the IBM 360 instruction set architecture but at a cheaper price. In 1974, it produced one of the first 32-bit minicomputers, the Interdata 7/32. The company then used the parallel processing approach, which uses more than one computer processor simultaneously to perform work on a problem. This helped in making real-time computing a reality.
Ferranti's Argus computers were a line of industrial control computers offered from the 1960s into the 1980s. Originally designed for a military role, a re-packaged Argus was the first digital computer to be used to directly control an entire factory. They were widely used in a variety of roles in Europe, particularly in the UK, where a small number continue to serve as monitoring and control systems for nuclear reactors.
In computer architecture, 16-bit integers, memory addresses, or other data units are those that are 16 bits wide. Also, 16-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers, address buses, or data buses of that size. 16-bit microcomputers are microcomputers that use 16-bit microprocessors.
Computer Automation, Inc. was a computer manufacturer founded by David H. Methvin in 1968, based originally in Newport Beach, California, United States. It opened a sales, support and repair arm in the UK in 1972, based at Hertford House, Maple Cross, Rickmansworth, Hertfordshire. Later relocated to Suite 2 Milfield House, Croxley Centre, Croxley Green, Watford, Hertfordshire.
Parallel Computers, Inc. was an American computer manufacturing company, based in Santa Cruz, California, that made fault-tolerant computer systems based around the Unix operating system and various processors in the Motorola 68000 series.
The Raytheon 704 is a 16-bit minicomputer introduced by Raytheon in 1970. It was an updated and repackaged version of the Raytheon 703 with new input/output features. The basic machine contained 4 kwords (8 kB) of memory and a simple arithmetic logic unit (ALU) running at 1 MHz. It was normally operated with a Teletype Model 33 acting as a computer terminal. It sold for "less than $10,000".
