cosrom256_w3.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*3/1024);

entity COSROM256_W3 is
    port(
        addr            :in std_logic_vector(7 downto 0);
        cos_w3          :out std_logic_vector(31 downto 0)
    );
end COSROM256_W3;

architecture behavior of COSROM256_W3 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'("01111111111110100111001011010000"),--address=1
        ROMWORD'("01111111111010011100101110111110"),--address=2
        ROMWORD'("01111111110011100000110000111101"),--address=3
        ROMWORD'("01111111101001110011011010110010"),--address=4
        ROMWORD'("01111111011101010100111001111110"),--address=5
        ROMWORD'("01111111001110000101011111110011"),--address=6
        ROMWORD'("01111110111100000101100001011101"),--address=7
        ROMWORD'("01111110100111010101010111111001"),--address=8
        ROMWORD'("01111110001111110101011111111100"),--address=9
        ROMWORD'("01111101110101100110011010001011"),--address=10
        ROMWORD'("01111101011000101000101011000010"),--address=11
        ROMWORD'("01111100111000111100111010101101"),--address=12
        ROMWORD'("01111100010110100011110101001011"),--address=13
        ROMWORD'("01111011110001011110001010001010"),--address=14
        ROMWORD'("01111011001001101100101101001001"),--address=15
        ROMWORD'("01111010011111010000010101010101"),--address=16
        ROMWORD'("01111001110010001001111101100110"),--address=17
        ROMWORD'("01111001000010011010100100100101"),--address=18
        ROMWORD'("01111000010000000011001100100000"),--address=19
        ROMWORD'("01110111011011000100111011010010"),--address=20
        ROMWORD'("01110110100011100000111010011011"),--address=21
        ROMWORD'("01110101101001011000010111000100"),--address=22
        ROMWORD'("01110100101100101100100001111000"),--address=23
        ROMWORD'("01110011101101011110101111000100"),--address=24
        ROMWORD'("01110010101011110000010110011001"),--address=25
        ROMWORD'("01110001100111100010110011000100"),--address=26
        ROMWORD'("01110000100000110111100011101111"),--address=27
        ROMWORD'("01101111010111110000001010100001"),--address=28
        ROMWORD'("01101110001100001110001100111000"),--address=29
        ROMWORD'("01101100111110010011010011101001"),--address=30
        ROMWORD'("01101011101110000001001010111101"),--address=31
        ROMWORD'("01101010011011011001100010001111"),--address=32
        ROMWORD'("01101001000110011110001100001010"),--address=33
        ROMWORD'("01100111101111010000111110100101"),--address=34
        ROMWORD'("01100110010101110011110010100011"),--address=35
        ROMWORD'("01100100111010001000100100001101"),--address=36
        ROMWORD'("01100011011100010001010010110001"),--address=37
        ROMWORD'("01100001111100010000000000100011"),--address=38
        ROMWORD'("01100000011010000110110010110001"),--address=39
        ROMWORD'("01011110110101110111110001101011"),--address=40
        ROMWORD'("01011101001111100101001000010111"),--address=41
        ROMWORD'("01011011100111010001000100110010"),--address=42
        ROMWORD'("01011001111100111101110111101111"),--address=43
        ROMWORD'("01011000010000101101110100110000"),--address=44
        ROMWORD'("01010110100010100011010010000100"),--address=45
        ROMWORD'("01010100110010100000101000100011"),--address=46
        ROMWORD'("01010011000000101000010011101111"),--address=47
        ROMWORD'("01010001001100111100110001101010"),--address=48
        ROMWORD'("01001111010111100000100010111000"),--address=49
        ROMWORD'("01001101100000010110001010010111"),--address=50
        ROMWORD'("01001011100111100000001101100001"),--address=51
        ROMWORD'("01001001101101000001010100000100"),--address=52
        ROMWORD'("01000111110000111100000111111110"),--address=53
        ROMWORD'("01000101110011010011010101011101"),--address=54
        ROMWORD'("01000011110100001001101010111000"),--address=55
        ROMWORD'("01000001110011100001111000101111"),--address=56
        ROMWORD'("00111111110001011110110001100000"),--address=57
        ROMWORD'("00111101101110000011001001101101"),--address=58
        ROMWORD'("00111011101001010001110111101111"),--address=59
        ROMWORD'("00111001100011001101110011110110"),--address=60
        ROMWORD'("00110111011011111001111000001001"),--address=61
        ROMWORD'("00110101010011011001000000011000"),--address=62
        ROMWORD'("00110011001001101110001010000010"),--address=63
        ROMWORD'("00110000111110111100010100001011"),--address=64
        ROMWORD'("00101110110011000110011111011011"),--address=65
        ROMWORD'("00101100100110001111101101110110"),--address=66
        ROMWORD'("00101010011000011011000010111011"),--address=67
        ROMWORD'("00101000001001101011100011100000"),--address=68
        ROMWORD'("00100101111010000100010101101101"),--address=69
        ROMWORD'("00100011101001101000100000110100"),--address=70
        ROMWORD'("00100001011000011011001101010100"),--address=71
        ROMWORD'("00011111000110011111100100101110"),--address=72
        ROMWORD'("00011100110011111000110001100100"),--address=73
        ROMWORD'("00011010100000101001111111010101"),--address=74
        ROMWORD'("00011000001100110110011010010111"),--address=75
        ROMWORD'("00010101111000100001001111110010"),--address=76
        ROMWORD'("00010011100011101101101101011100"),--address=77
        ROMWORD'("00010001001110011111000001111001"),--address=78
        ROMWORD'("00001110111000111000011100001111"),--address=79
        ROMWORD'("00001100100010111101001100000110"),--address=80
        ROMWORD'("00001010001100110000100001100011"),--address=81
        ROMWORD'("00000111110110010101101101000100"),--address=82
        ROMWORD'("00000101011111101111111111011001"),--address=83
        ROMWORD'("00000011001001000010101001100010"),--address=84
        ROMWORD'("00000000110010010000111100101010"),--address=85
        ROMWORD'("11111110011011011110001010000010"),--address=86
        ROMWORD'("11111100000100101101100010111011"),--address=87
        ROMWORD'("11111001101110000010011000100100"),--address=88
        ROMWORD'("11110111010111011111111100000100"),--address=89
        ROMWORD'("11110101000001001001011110011001"),--address=90
        ROMWORD'("11110010101011000010010000001011"),--address=91
        ROMWORD'("11110000010101001101100001110001"),--address=92
        ROMWORD'("11101101111111101110100011000110"),--address=93
        ROMWORD'("11101011101010101000100011101001"),--address=94
        ROMWORD'("11101001010101111110110010010101"),--address=95
        ROMWORD'("11100111000001110100011101011101"),--address=96
        ROMWORD'("11100100101110001100110010101001"),--address=97
        ROMWORD'("11100010011011001010111110110011"),--address=98
        ROMWORD'("11100000001000110010001101111100"),--address=99
        ROMWORD'("11011101110111000101101011010001"),--address=100
        ROMWORD'("11011011100110001000100000111111"),--address=101
        ROMWORD'("11011001010101111101111000010000"),--address=102
        ROMWORD'("11010111000110101000111001001011"),--address=103
        ROMWORD'("11010100111000001100101010101010"),--address=104
        ROMWORD'("11010010101010101100010010011001"),--address=105
        ROMWORD'("11010000011110001010110100110010"),--address=106
        ROMWORD'("11001110010010101011010100110111"),--address=107
        ROMWORD'("11001100001000010000110100001101"),--address=108
        ROMWORD'("11001001111110111110010010111011"),--address=109
        ROMWORD'("11000111110110110110101111100100"),--address=110
        ROMWORD'("11000101101111111101000111000010"),--address=111
        ROMWORD'("11000011101010010100010100100100"),--address=112
        ROMWORD'("11000001100101111111010001101000"),--address=113