arithmetic and logic unit

1 definition found

arithmetic and logic unit - Free On-line Dictionary of Computing (26 May 2007) :

  Arithmetic and Logic Unit
  mill
  
     <processor> (ALU or "mill") The part of the central processing unit
      which performs operations such as addition,
     subtraction and multiplication of integers and bit-wise
     AND, OR, NOT, XOR and other Boolean operations.  The
     CPU's instruction decode logic determines which particular
     operation the ALU should perform, the source of the operands
     and the destination of the result.
  
     The width in bits of the words which the ALU handles is
     usually the same as that quoted for the processor as a whole
     whereas its external busses may be narrower.  Floating-point
     operations are usually done by a separate "floating-point unit
     ".  Some processors use the ALU for address calculations
     (e.g. incrementing the program counter), others have
     separate logic for this.
  
     (1995-03-24)