------------------------------------------------------------------------------ -- This file is a part of the LPP VHDL IP LIBRARY -- Copyright (C) 2009 - 2013, Laboratory of Plasmas Physic - CNRS -- -- This program 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 3 of the License, or -- (at your option) any later version. -- -- This program 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 this program; if not, write to the Free Software -- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA ------------------------------------------------------------------------------ -- Author : Alexis Jeandet -- Mail : alexis.jeandet@member.fsf.org ------------------------------------------------------------------------------ -- -- This module implements the Slow to Slow Fast transfer: -- Data Transfer between Asynchronous Clock Domains without Pain -- from Markus Schutti, Markus Pfaff, Richard Hagelauer -- http://www-micrel.deis.unibo.it/~benini/files/SNUG/paper9_final.pdf -- see page 5 -- -- library IEEE; use IEEE.STD_LOGIC_1164.ALL; entity Slow2FastSync is generic ( N : integer range 0 to 256:=8 ); Port ( Data : in STD_LOGIC_VECTOR (N-1 downto 0); ClockF : in STD_LOGIC; ClockS : in STD_LOGIC; SyncSignal : in STD_LOGIC; DataSinkS : out STD_LOGIC_VECTOR (N-1 downto 0) ); end Slow2FastSync; architecture AR_Slow2FastSync of Slow2FastSync is signal DataS : STD_LOGIC_VECTOR (N-1 downto 0); begin process(ClockF) begin if ClockF'event and ClockF = '1' and SyncSignal = '1' then DataSinkS <= DataS; end if; end process; process(ClockS) begin if ClockS'event and ClockS = '1' then DataS <= Data; end if; end process; end AR_Slow2FastSync;