From a170b9b42345794429486dd4f3316e84ea2cc871 Mon Sep 17 00:00:00 2001 From: Josh Blum Date: Fri, 22 Jan 2010 11:46:58 -0800 Subject: Moved usrp1 fpga files into usrp1 subdir. --- usrp1/sdr_lib/clk_divider.v | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100755 usrp1/sdr_lib/clk_divider.v (limited to 'usrp1/sdr_lib/clk_divider.v') diff --git a/usrp1/sdr_lib/clk_divider.v b/usrp1/sdr_lib/clk_divider.v new file mode 100755 index 000000000..fdef234d2 --- /dev/null +++ b/usrp1/sdr_lib/clk_divider.v @@ -0,0 +1,43 @@ +// -*- 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 + -- cgit v1.2.3