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(*
Confluence System Design Library
Copyright (C) 2003-2004 Tom Hawkins (tomahawkins@yahoo.com)
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*)
(** Cross clock domain synchronization. *)
synchronizer
is
(** See link for more info: http://www.e-insite.net/ednmag/index.asp?layout=article&articleid=CA276202 *)
component synchronizer +clk_src +clk_dst +start -take_it -got_it with
take_it_1 take_it_2 take_it_3
got_it_1 got_it_2 got_it_3 is
(* start to take_it. *)
{clock clk_src {reg 1 (start '^' take_it_1) take_it_1}}
{clock clk_dst {regs 1 2 take_it_1 take_it_2}}
{clock clk_dst {reg 1 take_it_2 take_it_3}}
take_it = take_it_2 '^' take_it_3
(* take_it back to got_it. *)
{clock clk_dst {reg 1 (take_it '^' got_it_1) got_it_1}}
{clock clk_src {regs 1 2 got_it_1 got_it_2}}
{clock clk_src {reg 1 got_it_2 got_it_3}}
got_it = got_it_2 '^' got_it_3
end
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