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// -*- verilog -*-
//
// USRP - Universal Software Radio Peripheral
//
// Copyright (C) 2007 Corgan Enterprises 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 2 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, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Boston, MA 02110-1301 USA
//
module lfsr_constants(clk_i,rst_i,degree_i,mask_o,len_o);
input clk_i;
input rst_i;
input [4:0] degree_i;
output reg [15:0] mask_o;
output reg [16:0] len_o;
integer len;
always @(posedge clk_i)
if (rst_i)
begin
len_o <= #5 17'b0;
mask_o <= #5 16'b0;
end
else
begin
len_o <= #5 ((1 << degree_i) << 1)-3;
case (degree_i)
5'd00: mask_o <= #5 16'h0000;
5'd01: mask_o <= #5 16'h0001;
5'd02: mask_o <= #5 16'h0003;
5'd03: mask_o <= #5 16'h0005;
5'd04: mask_o <= #5 16'h0009;
5'd05: mask_o <= #5 16'h0012;
5'd06: mask_o <= #5 16'h0021;
5'd07: mask_o <= #5 16'h0041;
5'd08: mask_o <= #5 16'h008E;
5'd09: mask_o <= #5 16'h0108;
5'd10: mask_o <= #5 16'h0204;
5'd11: mask_o <= #5 16'h0402;
5'd12: mask_o <= #5 16'h0829;
5'd13: mask_o <= #5 16'h100D;
5'd14: mask_o <= #5 16'h2015;
5'd15: mask_o <= #5 16'h4001;
5'd16: mask_o <= #5 16'h8016;
default: mask_o <= #5 16'h0000;
endcase // case(degree_i)
end // else: !if(rst_i)
endmodule // lfsr_constants
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