cosrom256_w2.vhd

8-1024可变点数FFT/IFFT变换,VHDL语言设计, 仿真通过,可以很容易综合.

--************************************************************
--************************************************************
--*----------------------------------------------------------*
--*|Version                               :1.0               |
--*|Date of Last Revision                 :12/23/1998        |
--*----------------------------------------------------------*
--************************************************************
-- Copyright (C) 1999 Drey Enterprises Inc.   All Rights Reserved.
--************************************************************
-- Warning: This file is protected by Federal Copyright Law,
-- with all rights reserved. It is unlawful to reproduce
-- any parts of this file, in any form, without expressed
-- written permission from Drey Enterprises Inc. This Copyright
-- is actively enforced.
--************************************************************
--************************************************************

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.std_logic_unsigned.all;

-- cos(2*pi*n*2/1024);

entity COSROM256_W2 is
    port(
        addr           :in std_logic_vector(7 downto 0);
        cos_w2         :out std_logic_vector(31 downto 0)
    );
end COSROM256_W2;

architecture behavior of COSROM256_W2 is

    constant ROM_WIDTH:integer := 32;
    subtype ROMWORD is std_logic_vector(ROM_WIDTH-1 downto 0);
    type ROM_TABLE is array(0 to 255) of ROMWORD;

    constant ROM:ROM_TABLE := ROM_TABLE'(
        ROMWORD'("01111111111111111111111111111111"),--address=0
        ROMWORD'("01111111111111011000100001011001"),--address=1
        ROMWORD'("01111111111101100010000110000001"),--address=2
        ROMWORD'("01111111111010011100101110111110"),--address=3
        ROMWORD'("01111111110110001000011110001100"),--address=4
        ROMWORD'("01111111110000100101010110010101"),--address=5
        ROMWORD'("01111111101001110011011010110010"),--address=6
        ROMWORD'("01111111100001110010101111110001"),--address=7
        ROMWORD'("01111111011000100011011010001101"),--address=8
        ROMWORD'("01111111001110000101011111110011"),--address=9
        ROMWORD'("01111111000010011001000111000001"),--address=10
        ROMWORD'("01111110110101011110010111000100"),--address=11
        ROMWORD'("01111110100111010101010111111001"),--address=12
        ROMWORD'("01111110010111111110010010010000"),--address=13
        ROMWORD'("01111110000111011001001111100111"),--address=14
        ROMWORD'("01111101110101100110011010001011"),--address=15
        ROMWORD'("01111101100010100101111100111100"),--address=16
        ROMWORD'("01111101001110011000000011101000"),--address=17
        ROMWORD'("01111100111000111100111010101101"),--address=18
        ROMWORD'("01111100100010010100101111011001"),--address=19
        ROMWORD'("01111100001010011111101111101001"),--address=20
        ROMWORD'("01111011110001011110001010001010"),--address=21
        ROMWORD'("01111011010111010000001110011000"),--address=22
        ROMWORD'("01111010111011110110001100011101"),--address=23
        ROMWORD'("01111010011111010000010101010101"),--address=24
        ROMWORD'("01111010000001011110111010100110"),--address=25
        ROMWORD'("01111001100010100010001110101010"),--address=26
        ROMWORD'("01111001000010011010100100100101"),--address=27
        ROMWORD'("01111000100001001000010000001011"),--address=28
        ROMWORD'("01110111111110101011100110000000"),--address=29
        ROMWORD'("01110111011011000100111011010010"),--address=30
        ROMWORD'("01110110110110010100100101111111"),--address=31
        ROMWORD'("01110110010000011010111100110010"),--address=32
        ROMWORD'("01110101101001011000010111000100"),--address=33
        ROMWORD'("01110101000001001101001100111010"),--address=34
        ROMWORD'("01110100010111111001110111000101"),--address=35
        ROMWORD'("01110011101101011110101111000100"),--address=36
        ROMWORD'("01110011000001111100001111000011"),--address=37
        ROMWORD'("01110010010101010010110001110111"),--address=38
        ROMWORD'("01110001100111100010110011000100"),--address=39
        ROMWORD'("01110000111000101100101110110111"),--address=40
        ROMWORD'("01110000001000110001000010001010"),--address=41
        ROMWORD'("01101111010111110000001010100001"),--address=42
        ROMWORD'("01101110100101101010100110001100"),--address=43
        ROMWORD'("01101101110010100000110100000010"),--address=44
        ROMWORD'("01101100111110010011010011101001"),--address=45
        ROMWORD'("01101100001001000010100101001101"),--address=46
        ROMWORD'("01101011010010101111001001100100"),--address=47
        ROMWORD'("01101010011011011001100010001111"),--address=48
        ROMWORD'("01101001100011000010010001010110"),--address=49
        ROMWORD'("01101000101001101001111001101011"),--address=50
        ROMWORD'("01100111101111010000111110100101"),--address=51
        ROMWORD'("01100110110011111000000100001000"),--address=52
        ROMWORD'("01100101110111011111101110111010"),--address=53
        ROMWORD'("01100100111010001000100100001101"),--address=54
        ROMWORD'("01100011111011110011001001110101"),--address=55
        ROMWORD'("01100010111100100000000110010001"),--address=56
        ROMWORD'("01100001111100010000000000100011"),--address=57
        ROMWORD'("01100000111011000011100000010011"),--address=58
        ROMWORD'("01011111111000111011001101101111"),--address=59
        ROMWORD'("01011110110101110111110001101011"),--address=60
        ROMWORD'("01011101110001111001110101011100"),--address=61
        ROMWORD'("01011100101101000010000010111111"),--address=62
        ROMWORD'("01011011100111010001000100110010"),--address=63
        ROMWORD'("01011010100000100111100101111000"),--address=64
        ROMWORD'("01011001011001000110010001110100"),--address=65
        ROMWORD'("01011000010000101101110100110000"),--address=66
        ROMWORD'("01010111000111011110111011010100"),--address=67
        ROMWORD'("01010101111101011010010010101100"),--address=68
        ROMWORD'("01010100110010100000101000100011"),--address=69
        ROMWORD'("01010011100110110010101011001000"),--address=70
        ROMWORD'("01010010011010010001001001000101"),--address=71
        ROMWORD'("01010001001100111100110001101010"),--address=72
        ROMWORD'("01001111111110110110010100100010"),--address=73
        ROMWORD'("01001110101111111110100001111001"),--address=74
        ROMWORD'("01001101100000010110001010010111"),--address=75
        ROMWORD'("01001100001111111101111111000110"),--address=76
        ROMWORD'("01001010111110110110110001101001"),--address=77
        ROMWORD'("01001001101101000001010100000100"),--address=78
        ROMWORD'("01001000011010011110011000110100"),--address=79
        ROMWORD'("01000111000111001110110010110101"),--address=80
        ROMWORD'("01000101110011010011010101011101"),--address=81
        ROMWORD'("01000100011110101100110100011101"),--address=82
        ROMWORD'("01000011001001011100000100000001"),--address=83
        ROMWORD'("01000001110011100001111000101111"),--address=84
        ROMWORD'("01000000011100111111000111100110"),--address=85
        ROMWORD'("00111111000101110100100110000000"),--address=86
        ROMWORD'("00111101101110000011001001101101"),--address=87
        ROMWORD'("00111100010101101011101000110110"),--address=88
        ROMWORD'("00111010111100101110111001111100"),--address=89
        ROMWORD'("00111001100011001101110011110110"),--address=90
        ROMWORD'("00111000001001001001001101110011"),--address=91
        ROMWORD'("00110110101110100001111111010110"),--address=92
        ROMWORD'("00110101010011011001000000011000"),--address=93
        ROMWORD'("00110011110111101111001001000111"),--address=94
        ROMWORD'("00110010011011100101010010000111"),--address=95
        ROMWORD'("00110000111110111100010100001011"),--address=96
        ROMWORD'("00101111100001110101001000011111"),--address=97
        ROMWORD'("00101110000100010000101000011110"),--address=98
        ROMWORD'("00101100100110001111101101110110"),--address=99
        ROMWORD'("00101011000111110011010010100101"),--address=100
        ROMWORD'("00101001101000111100010000111110"),--address=101
        ROMWORD'("00101000001001101011100011100000"),--address=102
        ROMWORD'("00100110101010000010000100111101"),--address=103
        ROMWORD'("00100101001010000000110000010100"),--address=104
        ROMWORD'("00100011101001101000100000110100"),--address=105
        ROMWORD'("00100010001000111010010001111010"),--address=106
        ROMWORD'("00100000100111110110111111010000"),--address=107
        ROMWORD'("00011111000110011111100100101110"),--address=108
        ROMWORD'("00011101100100110100111110010111"),--address=109
        ROMWORD'("00011100000010111000001000011011"),--address=110
        ROMWORD'("00011010100000101001111111010101"),--address=111
        ROMWORD'("00011000111110001011011111101011"),--address=112
        ROMWORD'("00010111011011011101100110001100"),--address=113