-- 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: ap_a_fg_a_02.vhd,v 1.2 2001-10-26 16:29:33 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------

entity fg_a_02 is

end entity fg_a_02;


library ieee;  use ieee.std_logic_1164.all;

architecture test of fg_a_02 is

  signal clk, a, b : std_ulogic;

begin

  stimulus : process is
  begin
    clk <= '0';  a <= '0';  b <= '0';  wait for 10 ns;
    clk <= '1', '0' after 10 ns;  wait for 20 ns;
    b <= '1';  wait for 10 ns;
    clk <= '1', '0' after 20 ns;  a <= '0' after 10 ns;

    wait;
  end process stimulus;


  b1 : block is
               signal q : std_ulogic;
  begin

    -- code from book

    process (clk) is
                    variable d : std_ulogic;
    begin
      if a = b then
        d := '1';
      else
        d := '0';
      end if;
      if rising_edge(clk) then
        q <= d;
      end if;
    end process;

    -- end code from book

  end block b1;



  b2 : block is
               signal q : std_ulogic;
  begin

    -- code from book

    process (clk) is
    begin
      if rising_edge(clk) then
        if a = b then
          q <= '1';
        else
          q <= '0';
        end if;
      end if;
    end process;

    -- end code from book

  end block b2;

end architecture test;