fft.v

fft代码,采用蝶形算法,包括C,matlab和verilog代码

module sequential__adder(a, b, sum, clock);
parameter width = 1;
input  [width-1:0] a;
input  [width-1:0] b;
input  clock;
output [width-1:0] sum;
reg    [width-1:0] sum;

always @(posedge clk)
  sum = a + b;

endmodule


module sequential_subtractor(a, b, difference, clock);
parameter width = 1;
input  [width-1:0] a;
input  [width-1:0] b;
input  clock;
output [width-1:0] difference;
reg    [width-1:0] difference;

always @(posedge clk)
  difference = a - b;

endmodule


module real_butterfly(in0, in1, out0 out1, clock);
parameter width = 1;
input  [width-1:0] in0;
input  [width-1:0] in1;
input  clock;
output [width-1:0] out0;
output [width-1:0] out1;
reg    [width-1:0] out0;
reg    [width-1:0] out1;

sequential_adder      #(width) positive (in0, in1, out0, clock);
sequential_subtractor #(width) negative (in0, in1, out1, clock);

endmodule


module complex_butterfly(re_in0, im_in0, re_in1, im_in1, re_out0, im_out0, re_out1, im_out1, clock);
parameter width = 1;
input  [width-1:0] re_in0;
input  [width-1:0] im_in0;
input  [width-1:0] re_in1;
input  [width-1:0] im_in1;
input  clock;
output [width-1:0] re_out0;
output [width-1:0] im_out0;
output [width-1:0] re_out1;
output [width-1:0] im_out1;
reg    [width-1:0] re_out0;
reg    [width-1:0] im_out0;
reg    [width-1:0] re_out1;
reg    [width-1:0] im_out1;

real_butterfly #(width) re_part (re_in0, re_in1, re_out0 re_out1, clock)
imag_butterfly #(width) im_part (im_in0, im_in1, im_out0 im_out1, clock)

endmodule


module multiplexor(in0, in1, select, out, clock);
parameter width = 1;
input  [width-1:0] in0;
input  [width-1:0] in1;
input  select;
input  clock;
output [width-1:0] out;
reg    [width-1:0] out;

always @(posedge clock)
  if(select)
    out = in1;
  else
    out = in0;

endmodule


module delay(in, length, out, clock);
parameter width = 1;
input  [width-1:0] in;
input  clock;
output [width-1:0] out;
reg    [width-1:0] out;


endmodule