image.png

Shouldn't it be

module #(
...
) frequency_counter (
...
);

Yep thanks I figured it out 🙂

Also, if you want to parameterise your ports using

localparam

instead of

parameter

I think you'll nee to take the Verilog 2005 approach of having a coma separated port list and then declaring the ports under your

localparam

deceleration in the module body. A bit of a nuisance I know.

module mymodule
    (
        bin_i,
        onehot_o
    );

    parameter SZX;

    localparam SZ=2**SZX;

    input  wire [SZX-1:0] bin_i;
    output wire  [SZ-1:0] onehot_o;

In which case, this would also do the trick

module mymodule #
(
   parameter DATA_WIDTH = 32                // width of data bus in bits (8, 16, 32, or 64)
)
(
   input [DATA_WIDTH-1:0] bin_i
)