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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
library ieee; use ieee.std_logic_1164.all;
package synchronize is
procedure init_synchronize ( signal synch : out std_logic );
procedure begin_synchronize ( signal synch : inout std_logic;
Tdelay : in delay_length := 0 fs );
procedure end_synchronize ( signal synch : inout std_logic;
Tdelay : in delay_length := 0 fs );
end package synchronize;
package body synchronize is
-- code from book
procedure init_synchronize ( signal synch : out std_logic ) is
begin
synch <= '0';
end procedure init_synchronize;
procedure begin_synchronize ( signal synch : inout std_logic;
Tdelay : in delay_length := 0 fs ) is
begin
synch <= 'Z' after Tdelay;
wait until synch = 'H';
end procedure begin_synchronize;
procedure end_synchronize ( signal synch : inout std_logic;
Tdelay : in delay_length := 0 fs ) is
begin
synch <= '0' after Tdelay;
wait until synch = '0';
end procedure end_synchronize;
-- end code from book
end package body synchronize;
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