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-- Copyright (C) 2002 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
package constraints is
-- code from book (in text)
group port_pair is ( signal, signal );
attribute max_prop_delay : time;
-- end code from book
end package constraints;
-- code from book
library ieee; use ieee.std_logic_1164.all;
use work.constraints.port_pair, work.constraints.max_prop_delay;
entity clock_buffer is
port ( clock_in : in std_logic;
clock_out1, clock_out2, clock_out3 : out std_logic );
group clock_to_out1 : port_pair ( clock_in, clock_out1 );
group clock_to_out2 : port_pair ( clock_in, clock_out2 );
group clock_to_out3 : port_pair ( clock_in, clock_out3 );
attribute max_prop_delay of clock_to_out1 : group is 2 ns;
attribute max_prop_delay of clock_to_out2 : group is 2 ns;
attribute max_prop_delay of clock_to_out3 : group is 2 ns;
end entity clock_buffer;
-- end code from book
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