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-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc
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-- This file is part of VESTs (Vhdl tESTs).
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-- VESTs is free software; you can redistribute it and/or modify it
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-- under the terms of the GNU General Public License as published by the
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-- Free Software Foundation; either version 2 of the License, or (at
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-- your option) any later version.
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-- VESTs is distributed in the hope that it will be useful, but WITHOUT
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-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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-- for more details.
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-- You should have received a copy of the GNU General Public License
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-- along with VESTs; if not, write to the Free Software Foundation,
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-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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-- ---------------------------------------------------------------------
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--
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-- $Id: ch_16_fg_16_14.vhd,v 1.2 2001-10-26 16:29:36 paw Exp $
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-- $Revision: 1.2 $
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--
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-- ---------------------------------------------------------------------
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-- not in book
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entity example_entity is
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end entity example_entity;
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-- end not in book
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architecture contrived of example_entity is
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constant sig_width : positive := 16;
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signal s1, s2, s3 : bit_vector (0 to sig_width - 1);
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signal sel : bit;
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-- . . .
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begin
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mux : block is
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generic ( width : positive );
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generic map ( width => sig_width );
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port ( d0, d1 : in bit_vector(0 to width - 1);
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y : out bit_vector(0 to width - 1);
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sel : in bit);
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port map ( d0 => s1, d1=> s2, y => s3, sel => sel );
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constant zero : bit_vector(0 to width - 1) := ( others => '0' );
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signal gated_d0, gated_d1 : bit_vector(0 to width - 1);
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begin
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gated_d0 <= d0 when sel = '0' else zero;
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gated_d1 <= d1 when sel = '1' else zero;
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y <= gated_d0 or gated_d1;
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end block mux;
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-- . . .
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-- not in book
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stimulus : process is
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begin
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s1 <= X"1111"; s2 <= X"2222"; sel <= '0'; wait for 10 ns;
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s1 <= X"0101"; wait for 10 ns;
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s2 <= X"0202"; wait for 10 ns;
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sel <= '1'; wait for 10 ns;
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s1 <= X"0001"; wait for 10 ns;
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s2 <= X"0002"; wait for 10 ns;
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wait;
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end process stimulus;
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-- end not in book
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end architecture contrived;
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