Microprocessor

2 definitions found

From WordNet (r) 2.0 [wn]:

  microprocessor
       n : integrated circuit semiconductor chip that performs the bulk
           of the processing and controls the parts of a system; "a
           microprocessor functions as the central processing unit
           of a microcomputer"; "a disk drive contains a
           microprocessor to handle the internal functions of the


           drive"

From The Free On-line Dictionary of Computing (27 SEP 03) [foldoc]:

  microprocessor
       
           (Or "micro") A computer whose entire {CPU} is
          contained on one (or a small number of) {integrated circuits}.
       
          The important characteristics of a microprocessor are the
          widths of its internal and external {address bus} and {data
          bus} (and instruction), its {clock rate} and its {instruction
          set}.  Processors are also often classified as either {RISC}
          or {CISC}.
       
          The first commercial microprocessor was the {Intel 4004} which
          appeared in 1971.  This was the CPU member of a set of four
          {LSI} {integrated circuits} called the MCS-4, which was
          originally designed for use in a calculator but was marketed
          as "programmable controller for logic replacement".  The 4004
          is referred to as a 4-bit microprocessor since it processed
          only 4 bits of data at a time.  This very short word size is
          due mainly to the limitations imposed by the maximum
          integrated circuit density then achievable.
       
          As integrated circuit densities increased with the rapid
          development of integrated circuit manufacturing technology,
          the power and performance of the microprocessors also
          increased.  This is reflected in the increase in the CPU word
          size to 4, 8, 16, and by mid-1980s, 32 bits.  The smaller
          microprocessors have relatively simple {instruction sets},
          e.g., no {floating point} instructions, but they are
          nevertheless suitable as controllers for a very wide range of
          applications such as car engines and microwave ovens.
       
          The {Intel 4004} was followed with, among others the {4040},
          {8008}, {8080}, {8086}, {80186}, {80286}, {80386}, {486} and
          {Pentium}.  Other families include the {Motorola} {6800} and
          {680x0} families, {National Semiconductor} {NS16000} and
          {NS32000}, {SPARC}, {ARM}, {MIPS}, {Zilog Z8000}, {PowerPC}
          and the {Inmos} {Transputer} family.
       
          The larger, more recent microprocessors families have
          gradually acquired most of the features of large computers.
          As the microprocessor industry has matured, several families
          of microprocessors have evolved into de facto industrial
          standards with multiple manufacturers and numerous "support"
          chips including {RAM}, {ROM}, {I/O controllers} etc.
       
          A single chip microprocessor may include other components such
          as memory ({RAM}, {ROM}, {PROM}), {memory management},
          {caches}, {floating-point unit}, input/output ports and
          timers.  Such devices are also known as {microcontrollers}.
       
          The one-chip microcomputer is in many respects, a landmark
          development in computer technology because it reduces the
          computer to a small, inexpensive, and easily replaceable
          design component.
       
          Microcomputers have given rise to a new class of
          general-purpose machines called {personal computer}s.  These
          are small low cost computers that are designed to sit on an
          ordinary office desk or to be portable and fuelled the
          computer boom of the late 1980s.  The most widespread example
          is the also {IBM PC}, based on microprocessors from {Intel
          Corporation}.  {Apple Computers, Inc.} have also produced a
          range of personal computers, as have several other companies.
       
          See also {killer micro}, {minicomputer}, {CPU Info Center}.
       
          (2002-07-16)