upsample.v

插值滤波器,用于音频解码调制解调,滤波器系数用移位相加实现

`timescale 1ns/10ps
module upsample(data_in,clock,reset,data_out);

input [18:1] data_in;
input clock,reset;
output [18:1] data_out;

reg [18:1] data_out;
reg [3:1] times;

always@(posedge clock or negedge reset)
    if(!reset)
       begin
         data_out=0;
         times=0;
       end
    else 
      begin
         if(!times)
            begin
              if(data_in)
                 begin 
                  data_out=data_in;
                  times=times+1;
                 end
            end     
         else
           begin
           data_out=0;
           times=times+1;
           if(times==3'b100)  
              times=0;
           end
      end

endmodule