diff options
Diffstat (limited to 'fpga/usrp1/sdr_lib/clk_divider.v')
-rwxr-xr-x | fpga/usrp1/sdr_lib/clk_divider.v | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/fpga/usrp1/sdr_lib/clk_divider.v b/fpga/usrp1/sdr_lib/clk_divider.v new file mode 100755 index 000000000..fdef234d2 --- /dev/null +++ b/fpga/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 + |