Subversion Repositories tv80

//
// Copyright (c) 2004 Guy Hutchison (ghutchis@opencores.org)
//
// Permission is hereby granted, free of charge, to any person obtaining a 
// copy of this software and associated documentation files (the "Software"), 
// to deal in the Software without restriction, including without limitation 
// the rights to use, copy, modify, merge, publish, distribute, sublicense, 
// and/or sell copies of the Software, and to permit persons to whom the 
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included 
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 
// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 
// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
// Simple wrapper for a clock synchronizer
//
// The following code can (should) be replaced with metastability-hardened
// flops from your technology library.
 
module sync2
  ( input     clk,
    input     data_in,
    output    data_out );
 
  reg         sync_ff1, sync_ff2;
 
  always @(posedge clk)
    begin
      sync_ff1 <= #1 data_in;
      sync_ff2 <= #1 sync_ff1;
    end
 
  assign data_out = sync_ff2;
 
endmodule // sync2