Subversion Repositories 1g_ethernet_dpi

//------------------------------------------------------------------------------
// File       : tri_mode_ethernet_mac_0_example_design_clock.v
// Author     : Xilinx Inc.
// -----------------------------------------------------------------------------
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// -----------------------------------------------------------------------------
// Description:  This block generates the clocking logic required for the
//               example design.
 
`timescale 1 ps/1 ps
 
module tri_mode_ethernet_mac_0_example_design_clocks
   (
   // differential clock inputs
   input          clk_in_p,
   input          clk_in_n,
 
   // asynchronous control/resets
   input          glbl_rst,
   output         dcm_locked,
 
   // clock outputs
   output         gtx_clk_bufg,
   output         refclk_bufg,
   output         s_axi_aclk
   );
 
 
   wire           clkin1;
   wire           mmcm_rst;
   wire           clkin1_bufg;
   wire           dcm_locked_int;
   wire           dcm_locked_sync;
   reg            dcm_locked_reg = 1;
   reg            dcm_locked_edge = 1;
 
  // Input buffering
  //------------------------------------
  IBUFDS clkin1_buf
   (.O  (clkin1),
    .I  (clk_in_p),
    .IB (clk_in_n));
 
  // route clkin1 through a BUFGCE for the MMCM reset generation logic
  BUFGCE bufg_clkin1 (.I(clkin1), .CE  (1'b1), .O(clkin1_bufg));
 
  // detect a falling edge on dcm_locked (after resyncing to this domain)
  tri_mode_ethernet_mac_0_sync_block lock_sync (
     .clk              (clkin1_bufg),
     .data_in          (dcm_locked_int),
     .data_out         (dcm_locked_sync)
  );
 
  // for the falling edge detect we want to force this at power on so init the flop to 1
  always @(posedge clkin1_bufg)
  begin
     dcm_locked_reg     <= dcm_locked_sync;
     dcm_locked_edge    <= dcm_locked_reg & !dcm_locked_sync;
  end
 
  // the MMCM reset should be at least 5ns - that is one cycle of the input clock -
  // since the source of the input reset is unknown (a push switch in board design)
  // this needs to be debounced
   tri_mode_ethernet_mac_0_reset_sync mmcm_reset_gen (
      .clk              (clkin1_bufg),
      .enable           (1'b1),
      .reset_in         (glbl_rst | dcm_locked_edge),
      .reset_out        (mmcm_rst)
   );
 
 
  //----------------------------------------------------------------------------
  // Generate clocks using the clock wizard
  //----------------------------------------------------------------------------
 
  tri_mode_ethernet_mac_0_clk_wiz clock_generator
  (
      // Clock in ports
      .CLK_IN1       (clkin1),
      // Clock out ports
      .CLK_OUT1      (gtx_clk_bufg),
      .CLK_OUT2      (s_axi_aclk),
      .CLK_OUT3      (refclk_bufg),
      // Status and control signals
      .RESET         (mmcm_rst),
      .LOCKED        (dcm_locked_int)
 );
 
 assign dcm_locked = dcm_locked_int;
 
 
 
endmodule