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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_16_fg_16_09.vhd,v 1.2 2001-10-26 16:29:36 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------
entity latch is
generic ( width : positive );
port ( enable : in bit;
d : in bit_vector(0 to width - 1);
q : out bit_vector(0 to width - 1) );
end entity latch;
--------------------------------------------------
architecture behavioral of latch is
begin
transfer_control : block ( enable = '1' ) is
begin
q <= guarded d;
end block transfer_control;
end architecture behavioral;
-- not in book
entity fg_16_09 is
end entity fg_16_09;
architecture test of fg_16_09 is
signal enable : bit := '0';
signal d, q : bit_vector(0 to 7);
begin
dut : entity work.latch(behavioral)
generic map ( width => 8 )
port map ( enable => enable, d => d, q => q );
stimulus : process is
begin
wait for 10 ns;
d <= X"11"; wait for 10 ns;
enable <= '1'; wait for 10 ns;
d <= X"AA"; wait for 10 ns;
enable <= '0'; wait for 10 ns;
d <= X"00"; wait for 10 ns;
wait;
end process stimulus;
end architecture test;
-- end not in book
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