fairchild f8

1 definition found

fairchild f8 - Free On-line Dictionary of Computing (26 May 2007) :

  Fairchild F8
  
     <processor> An 8-bit microprocessor.  The processor itself
     had no address bus - program and data memory access were
     contained in separate units, which reduced the number of pins
     and the associated cost.  It also featured 64 registers,
     accessed by the ISAR register in cells (register windows) of
     eight, which meant external RAM wasn't always needed for
     small applications.  In addition, the 2-chip processor didn't
     need support chips, unlike others which needed seven or more.
  
     The F8 inspired other similar CPUs, such as the Intel 8048
     .  The use of the ISAR register allowed a subroutine to
     be entered without saving a bunch of registers, speeding
     execution - the ISAR would just be changed.  Special purpose
     registers were stored in the second cell (regs 9-15), and the
     first eight registers were accessed directly.  The windowing
     concept was useful, but only the register pointed to by the
     ISAR could be accessed - to access other registers the ISAR
     was incremented or decremented through the window.
  
     (1994-11-16)