// file: bclk_dll_exdes.v
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//----------------------------------------------------------------------------
// Clocking wizard example design
//----------------------------------------------------------------------------
// This example design instantiates the created clocking network, where each
//   output clock drives a counter. The high bit of each counter is ported.
//----------------------------------------------------------------------------

`timescale 1ps/1ps

module bclk_dll_exdes 
 #( 
  parameter TCQ = 100
  )
 (// Clock in ports
  input         CLK_IN1,
  // Reset that only drives logic in example design
  input         COUNTER_RESET,
  output [1:1]  CLK_OUT,
  // High bits of counters driven by clocks
  output        COUNT,
  // Status and control signals
  input         RESET,
  output        LOCKED
 );

  // Parameters for the counters
  //-------------------------------
  // Counter width
  localparam    C_W       = 16;
  // When the clock goes out of lock, reset the counters
  wire          reset_int = !LOCKED || RESET || COUNTER_RESET;

   reg rst_sync;
   reg rst_sync_int;
   reg rst_sync_int1;
   reg rst_sync_int2;



  // Declare the clocks and counter
  wire           clk_int;
  wire           clk;
  reg  [C_W-1:0] counter;

  // Insert BUFGs on all input clocks that don't already have them
  //--------------------------------------------------------------
  BUFG clkin1_buf
   (.O (clk_in1_buf),
    .I (CLK_IN1));

  // Instantiation of the clocking network
  //--------------------------------------
  bclk_dll clknetwork
   (// Clock in ports
    .clk133in            (clk_in1_buf),
    // Clock out ports
    .clk133           (clk_int),
    // Status and control signals
    .RESET              (RESET),
    .LOCKED             (LOCKED));

  assign CLK_OUT[1] =  clk_int;

  // Connect the output clocks to the design
  //-----------------------------------------
  assign clk = clk_int;


  // Reset synchronizer
  //-----------------------------------
    always @(posedge reset_int or posedge clk) begin
       if (reset_int) begin
            rst_sync <= 1'b1;
            rst_sync_int <= 1'b1;
            rst_sync_int1 <= 1'b1;
            rst_sync_int2 <= 1'b1;
       end
       else begin
            rst_sync <= 1'b0;
            rst_sync_int <= rst_sync;     
            rst_sync_int1 <= rst_sync_int; 
            rst_sync_int2 <= rst_sync_int1;
       end
    end


  // Output clock sampling
  //-----------------------------------
  always @(posedge clk or posedge rst_sync_int2) begin
    if (rst_sync_int2) begin
      counter <= #TCQ { C_W { 1'b 0 } };
    end else begin
      counter <= #TCQ counter + 1'b 1;
    end
  end

  // alias the high bit to the output
  assign COUNT = counter[C_W-1];



endmodule
