// file: clkmgr_dcm_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 clkmgr_dcm_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 INPUT_CLK_STOPPED,
output CLK_VALID
);
// Parameters for the counters
//-------------------------------
// Counter width
localparam C_W = 16;
// Create reset for the counters
wire reset_int = 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_n;
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
//--------------------------------------
clkmgr_dcm clknetwork
(// Clock in ports
.CLK_IN1 (clk_in1_buf),
// Clock out ports
.CLK_OUT1 (clk_int),
// Status and control signals
.RESET (RESET),
.INPUT_CLK_STOPPED (INPUT_CLK_STOPPED),
.CLK_VALID (CLK_VALID));
assign clk_n = ~clk;
ODDR2 clkout_oddr
(.Q (CLK_OUT[1]),
.C0 (clk),
.C1 (clk_n),
.CE (1'b1),
.D0 (1'b1),
.D1 (1'b0),
.R (1'b0),
.S (1'b0));
// 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
