fft_pkg.vhd

来自「an implementation of fft 1024 with cos a」· VHDL 代码 · 共 20 行

library IEEE; 
USE ieee.std_logic_1164.ALL; 
USE ieee.std_logic_arith.ALL;
 
package fft_pkg is 
  type ioarray is array (integer range <>) of std_logic_vector(255 downto 0); 
  function log2(A: integer) return integer; 
 end;
 
package body fft_pkg is 
    function log2(A: integer) return integer is 
    begin 
    for I in 1 to 30 loop  -- Works for up to 32 bit integers   
           if (2**I > A) then return(I-1);
          end if; 
      end loop; 
    return(30); 
  end;   
end;