1 files changed, 46 insertions, 0 deletions
diff --git a/fpga/usrp2/control_lib/gray_send.v b/fpga/usrp2/control_lib/gray_send.v
new file mode 100644
index 000000000..62402f8d3
--- /dev/null
+++ b/fpga/usrp2/control_lib/gray_send.v
@@ -0,0 +1,46 @@
+//
+// Copyright 2011 Ettus Research 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 3 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, see <http://www.gnu.org/licenses/>.
+//
+
+
+
+
+module gray_send
+  #(parameter WIDTH = 8)
+    (input clk_in, input [WIDTH-1:0] addr_in,
+     input clk_out, output reg [WIDTH-1:0] addr_out);
+
+   reg [WIDTH-1:0] gray_clkin, gray_clkout, gray_clkout_d1;
+   wire [WIDTH-1:0] gray, bin;
+
+   bin2gray #(.WIDTH(WIDTH)) b2g (.bin(addr_in), .gray(gray) );
+
+   always @(posedge clk_in)
+     gray_clkin <= gray;
+
+   always @(posedge clk_out)
+     gray_clkout <= gray_clkin;
+
+   always @(posedge clk_out)
+     gray_clkout_d1 <= gray_clkout;
+   
+   gray2bin #(.WIDTH(WIDTH)) g2b (.gray(gray_clkout_d1), .bin(bin) );
+
+   // FIXME we may not need the next register, but it may help timing
+   always @(posedge clk_out)
+     addr_out <= bin;
+   
+endmodule // gray_send