cic_comb.v

/*
--------------------------------------------------------------------------------
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the
Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
Boston, MA  02110-1301, USA.
--------------------------------------------------------------------------------
*/

//------------------------------------------------------------------------------
//           Copyright (c) 2008 Alex Shovkoplyas, VE3NEA
//------------------------------------------------------------------------------

module cic_comb(clock, strobe, in_data, out_data);

parameter WIDTH = "required";

input clock;
input strobe;
input signed [WIDTH-1:0] in_data;
output reg signed [WIDTH-1:0] out_data;

reg signed [WIDTH-1:0] prev_data;
initial prev_data = 0;

always @(posedge clock)  
  if (strobe) 
    begin
    out_data <= in_data - prev_data;
    prev_data <= in_data;
    end

endmodule