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//----------------------------------------------------------------------------

// Decode rotary encoder to clk-syncronous signals

//

// (c) Joerg Bornschein (<jb@capsec.org>)

//----------------------------------------------------------------------------

module rotary (

        input        clk,

        input        reset,

        input [2:0]  rot,

        //

        output       rot_btn,

        output reg   rot_event,

        output reg   rot_left

);

assign rot_btn = 0;

//----------------------------------------------------------------------------

// decode rotary encoder

//----------------------------------------------------------------------------

parameter  counter_init = 10000000;

reg [31:0] counter;

reg rot_event2;

reg rot_left2;

always @(posedge clk)

begin

        if (reset)

                counter <= counter_init;

        else begin

                rot_event  <= rot_event2;

                rot_left   <= rot_left2;

                rot_event2 <= 0;

                rot_left2  <= 0;

                if (counter == 0) begin

                        counter <= counter_init;

                        if (rot[0] | rot[1])

                                rot_event2 <= 1;

                        if (rot[0])

                                rot_left2  <= 1;

                end else

                        counter <= counter - 1;

        end

end

endmodule