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//
// Copyright 2014 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: LGPL-3.0-or-later
//
module synchronizer_impl #(
parameter WIDTH = 1,
parameter STAGES = 2,
parameter INITIAL_VAL = 0
)(
input clk,
input rst,
input [WIDTH-1:0] in,
output [WIDTH-1:0] out
);
(* ASYNC_REG = "TRUE" *) reg [WIDTH-1:0] value[0:STAGES-1];
integer k;
initial begin
for (k = 0; k < STAGES; k = k + 1) begin
value[k] = INITIAL_VAL;
end
end
genvar i;
generate
for (i=0; i<STAGES; i=i+1) begin: stages
always @(posedge clk) begin
if (rst) begin
value[i] <= INITIAL_VAL;
end else begin
if (i == 0) begin
value[i] <= in;
end else begin
value[i] <= value[i-1];
end
end
end
end
endgenerate
assign out = value[STAGES-1];
endmodule //synchronizer_impl
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