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-- Copyright (C) 2002 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
library ieee; use ieee.std_logic_1164.all;
library ieee_proposed; use ieee_proposed.electrical_systems.all;
entity comparator is
port ( terminal a : electrical;
signal d : out std_ulogic );
end entity comparator;
----------------------------------------------------------------
architecture ideal of comparator is
constant ref_voltage : real := 5.0;
quantity vin across a;
begin
comparator_behavior : process is
begin
if vin > ref_voltage / 2.0 then
d <= '1' after 5 ns;
else
d <= '0' after 5 ns;
end if;
wait on vin'above(ref_voltage / 2.0);
end process comparator_behavior;
end architecture ideal;
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