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1 definition found
 for Motorola 68020
From The Free On-line Dictionary of Computing (30 December 2018) :

  Motorola 68020
  68020
  MC68020
  
      A microprocessor from Motorola.  It was the
     successor to the Motorola 68010 and was followed by the
     Motorola 68030.  The 68020 has 32-bit internal and external
     data and address buses and a 256-byte instruction buffer,
     arranged as 64 direct-mapped 4-byte entries[?].
  
     The 68020 added many improvements to the 68010 including a
     32-bit ALU and external data bus and address bus, and
     new instrucitons and addressing modes.  The 68020 (and
     68030) had a proper three-stage pipeline.
  
     The new instructions included some minor improvements and
     extensions to the supervisor state, some support for
     high-level languages which didn't get used much (and was
     removed from future 680x0 processors[?]), bigger (32 x 32-bit)
     multiply and divide instructions, and bit field manipulations.
  
     The new adderessing modes added another level of indirection
     to many of the pre-existing modes, and added quite a bit of
     flexibility to various indexing modes and operations.
  
     The instruction buffer (an instruction cache) was 256
     bytes, arranged as 64 direct-mapped 4-byte entries.  Although
     small, it made a significant difference in the performance of
     many applications.
  
     The 68881 and the faster 68882 FPU chips could be used with
     the 68020.
  
     The 68020 was used in many models of the Apple Macintosh II
     series of personal computers and Sun 3 workstations.
  
     (2001-03-07)
  

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