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// -*- verilog -*-
//
// USRP - Universal Software Radio Peripheral
//
// Copyright (C) 2003 Matt Ettus
//
// 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 clk_divider(input reset, input wire in_clk,output reg out_clk, input [7:0] ratio);
reg [7:0] counter;
// FIXME maybe should use PLL or switch to double edge version
always @(posedge in_clk or posedge reset)
if(reset)
counter <= #1 8'd0;
else if(counter == 0)
counter <= #1 ratio[7:1] + (ratio[0] & out_clk) - 8'b1;
else
counter <= #1 counter-8'd1;
always @(posedge in_clk or posedge reset)
if(reset)
out_clk <= #1 1'b0;
else if(counter == 0)
out_clk <= #1 ~out_clk;
endmodule // clk_divider
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