Page 299 - DSP Integrated Circuits

284 Chapter 7 DSP System Design

Figure 7.4 Signal-flow graph of a 16-point Sande-Tukey's FFT

—Package containing functions, types and constants to FFT-proc
library ieee;
use ieee.math_real.all;

package FFT_pckis
type Complex is record
re : real;
im : real;
end record;
constant M : integer := 10;
constant N : integer := 1024;
constant Nminusl: integer := 1023;
constant TwoPiN : real := 2.0*MATH_PI/real(N);
type complexArr is array(0 to Nminusl) of complex;
function Digit_Reverse(digit: integer) return integer;
procedure Unscramble(variable xx : inout complexArr);