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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_22.vhd,v 1.2 2001-10-26 16:29:34 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------

entity S_R_flipflop is
  port ( s, r : in bit;  q, q_n : out bit );
end entity S_R_flipflop;

--------------------------------------------------

architecture functional of S_R_flipflop is

begin

  q <= '1' when s = '1' else
       '0' when r = '1';

  q_n <= '0' when s = '1' else
         '1' when r = '1';

  check : assert not (s = '1' and r = '1')
    report "Incorrect use of S_R_flip_flop: s and r both '1'";

end architecture functional;