Subversion Repositories product_code_iterative_decoder

-- $Id: bit_comparator.vhdl,v 1.1.1.1 2005-11-15 01:52:30 arif_endro Exp $

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-- Title       : Bit comparator

-- Project     : 

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-- File        : bit_comparator.vhdl

-- Author      : "Arif E. Nugroho" <arif_endro@yahoo.com>

-- Created     : 2005/11/01

-- Last update : 

-- Simulators  :

-- Synthesizers: 

-- Target      : 

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-- Description : Compare two input

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-- Copyright (C) 2005 Arif Endro Nugroho

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-- 

--      THIS SOURCE FILE MAY BE USED AND DISTRIBUTED WITHOUT RESTRICTION

-- PROVIDED THAT THIS COPYRIGHT STATEMENT IS NOT REMOVED FROM THE FILE AND THAT

-- ANY DERIVATIVE WORK CONTAINS THE ORIGINAL COPYRIGHT NOTICE AND THE

-- ASSOCIATED DISCLAIMER.

-- 

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-- 

--      THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

-- IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

-- MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO

-- EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

-- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

-- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;

-- OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,

-- WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

-- OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

-- ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

-- 

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library IEEE;

use IEEE.std_logic_1164.all;

entity bit_comparator is

   port (

      a_i   : in  bit;

      b_i   : in  bit;

      eq_i  : in  bit;

      gt_i  : in  bit;

      lt_i  : in  bit;

      eq_o  : out bit;

      gt_o  : out bit;

      lt_o  : out bit

      );

end bit_comparator;

architecture data_flow of bit_comparator is

begin

     lt_o <= (((not(a_i) and lt_i) or (b_i and lt_i)) or (not(a_i) and b_i));

     eq_o <= (((a_i and b_i) and eq_i) or ((not(a_i) and not(b_i)) and eq_i));

     gt_o <= (((a_i and gt_i) or (not(b_i) and gt_i)) or (a_i and not(b_i)));

end data_flow;