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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
entity asym_delay is
end entity asym_delay;
architecture test of asym_delay is
signal a, z : bit;
begin
-- code from book
asym_delay : process (a) is
constant Tpd_01 : time := 800 ps;
constant Tpd_10 : time := 500 ps;
begin
if a = '1' then
z <= transport a after Tpd_01;
else -- a = '0'
z <= transport a after Tpd_10;
end if;
end process asym_delay;
-- end code from book
stimulus : process is
begin
a <= '1' after 2000 ps,
'0' after 4000 ps,
'1' after 6000 ps,
'0' after 6200 ps;
wait;
end process stimulus;
end architecture test;
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