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-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the
-- Free Software Foundation; either version 2 of the License, or (at
-- your option) any later version.
-- VESTs is distributed in the hope that it will be useful, but WITHOUT
-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
-- for more details.
-- You should have received a copy of the GNU General Public License
-- along with VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-- ---------------------------------------------------------------------
--
-- $Id: ch_05_fg_05_16.vhd,v 1.2 2001-10-26 16:29:34 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------
library ieee; use ieee.std_logic_1164.all;
entity and2 is
port ( a, b : in std_ulogic; y : out std_ulogic );
end entity and2;
--------------------------------------------------
architecture detailed_delay of and2 is
signal result : std_ulogic;
begin
gate : process (a, b) is
begin
result <= a and b;
end process gate;
delay : process (result) is
begin
if result = '1' then
y <= reject 400 ps inertial '1' after 1.5 ns;
elsif result = '0' then
y <= reject 300 ps inertial '0' after 1.2 ns;
else
y <= reject 300 ps inertial 'X' after 500 ps;
end if;
end process delay;
end architecture detailed_delay;
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