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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_ch_05_17.vhd,v 1.1.1.1 2001-08-22 18:20:47 paw Exp $
-- $Revision: 1.1.1.1 $
--
-- ---------------------------------------------------------------------
entity ch_05_17 is
end entity ch_05_17;
----------------------------------------------------------------
architecture test of ch_05_17 is
signal s, r, q, q_n : bit := '0';
begin
q <= '1' when s = '1' else
'0' when r = '1';
q_n <= '0' when s = '1' else
'1' when r = '1';
-- code from book:
check : process is
begin
assert not (s = '1' and r = '1')
report "Incorrect use of S_R_flip_flop: s and r both '1'";
wait on s, r;
end process check;
-- end of code from book
stimulus : process is
begin
wait for 10 ns;
s <= '1'; wait for 10 ns;
s <= '0'; wait for 10 ns;
r <= '1'; wait for 10 ns;
r <= '0'; wait for 10 ns;
s <= '1'; wait for 10 ns;
r <= '1'; wait for 10 ns;
s <= '0'; wait for 10 ns;
r <= '0'; wait for 10 ns;
wait;
end process stimulus;
end architecture test;
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