Merged r9433:9527 from features/gr-usrp2 into trunk. Adds usrp2 and gr-usrp2 top...
[debian/gnuradio] / usrp2 / fpga / control_lib / gray_send.v
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4 module gray_send
5   #(parameter WIDTH = 8)
6     (input clk_in, input [WIDTH-1:0] addr_in,
7      input clk_out, output reg [WIDTH-1:0] addr_out);
8
9    reg [WIDTH-1:0] gray_clkin, gray_clkout, gray_clkout_d1;
10    wire [WIDTH-1:0] gray, bin;
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12    bin2gray #(.WIDTH(WIDTH)) b2g (.bin(addr_in), .gray(gray) );
13
14    always @(posedge clk_in)
15      gray_clkin <= gray;
16
17    always @(posedge clk_out)
18      gray_clkout <= gray_clkin;
19
20    always @(posedge clk_out)
21      gray_clkout_d1 <= gray_clkout;
22    
23    gray2bin #(.WIDTH(WIDTH)) g2b (.gray(gray_clkout_d1), .bin(bin) );
24
25    // FIXME we may not need the next register, but it may help timing
26    always @(posedge clk_out)
27      addr_out <= bin;
28    
29 endmodule // gray_send