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//
// Copyright 2011-2012 Ettus Research LLC
//
// 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, see <http://www.gnu.org/licenses/>.
//


// 64 bits worth of ticks
//
// Not concerned with clock wrapping, human race will likely have extermintated it's self by this time.
//

module time_compare
  (
   input clk,
   input reset,
   input [63:0] time_now,
   input [63:0] trigger_time,
   output now,
   output early,
   output late,
   output too_early);

/*
   reg [63:0] time_diff;

   always @(posedge clk) begin
        if (reset) begin
            time_diff <= 64'b0;
            now <= 1'b0;
            late <= 1'b0;
            early <= 1'b0;
        end
        else begin
          time_diff <= trigger_time - time_now;
          now <= ~(|time_diff);
          late <= time_diff[63];
          early <= ~now & ~late;
       end
   end
   //assign now = ~(|time_diff);
   //assign late = time_diff[63];
   //assign early = ~now & ~late;
   assign too_early = 0; //not implemented
*/

    assign now = time_now == trigger_time;
    assign late = time_now > trigger_time;
    assign early = ~now & ~late;
    assign too_early = 0; //not implemented

endmodule // time_compare