testsuite/vests/vhdl-93/ashenden/compliant/ch_05_fg_05_05.vhd


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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_05.vhd,v 1.3 2001-11-03 23:19:37 paw Exp $
-- $Revision: 1.3 $
--
-- ---------------------------------------------------------------------

entity edge_triggered_Dff is
  port ( D : in bit;  clk : in bit;  clr : in bit;
  Q : out bit );
end entity edge_triggered_Dff;

architecture behavioral of edge_triggered_Dff is
begin

  state_change : process (clk, clr) is
  begin
    if clr = '1' then
      Q <= '0' after 2 ns;
    elsif clk'event and clk = '1' then
      Q <= D after 2 ns;
    end if;
  end process state_change;

end architecture behavioral;