cosrom256_w1.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*1/1024);

entity COSROM256_W1 is
    port(
        addr              :in std_logic_vector(7 downto 0);
        cos_w1            :out std_logic_vector(31 downto 0)
    );
end COSROM256_W1;

architecture behavior of COSROM256_W1 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'("01111111111111110110001000010101"),--address=1
        ROMWORD'("01111111111111011000100001011001"),--address=2
        ROMWORD'("01111111111110100111001011010000"),--address=3
        ROMWORD'("01111111111101100010000110000001"),--address=4
        ROMWORD'("01111111111100001001010001110110"),--address=5
        ROMWORD'("01111111111010011100101110111110"),--address=6
        ROMWORD'("01111111111000011100011101101010"),--address=7
        ROMWORD'("01111111110110001000011110001100"),--address=8
        ROMWORD'("01111111110011100000110000111101"),--address=9
        ROMWORD'("01111111110000100101010110010101"),--address=10
        ROMWORD'("01111111101101010110001110110001"),--address=11
        ROMWORD'("01111111101001110011011010110010"),--address=12
        ROMWORD'("01111111100101111100111010111011"),--address=13
        ROMWORD'("01111111100001110010101111110001"),--address=14
        ROMWORD'("01111111011101010100111001111110"),--address=15
        ROMWORD'("01111111011000100011011010001101"),--address=16
        ROMWORD'("01111111010011011110010001001110"),--address=17
        ROMWORD'("01111111001110000101011111110011"),--address=18
        ROMWORD'("01111111001000011001000110110010"),--address=19
        ROMWORD'("01111111000010011001000111000001"),--address=20
        ROMWORD'("01111110111100000101100001011101"),--address=21
        ROMWORD'("01111110110101011110010111000100"),--address=22
        ROMWORD'("01111110101110100011101000110110"),--address=23
        ROMWORD'("01111110100111010101010111111001"),--address=24
        ROMWORD'("01111110011111110011100101010100"),--address=25
        ROMWORD'("01111110010111111110010010010000"),--address=26
        ROMWORD'("01111110001111110101011111111100"),--address=27
        ROMWORD'("01111110000111011001001111100111"),--address=28
        ROMWORD'("01111101111110101001100010100100"),--address=29
        ROMWORD'("01111101110101100110011010001011"),--address=30
        ROMWORD'("01111101101100001111110111110100"),--address=31
        ROMWORD'("01111101100010100101111100111100"),--address=32
        ROMWORD'("01111101011000101000101011000010"),--address=33
        ROMWORD'("01111101001110011000000011101000"),--address=34
        ROMWORD'("01111101000011110100001000010100"),--address=35
        ROMWORD'("01111100111000111100111010101101"),--address=36
        ROMWORD'("01111100101101110010011100100000"),--address=37
        ROMWORD'("01111100100010010100101111011001"),--address=38
        ROMWORD'("01111100010110100011110101001011"),--address=39
        ROMWORD'("01111100001010011111101111101001"),--address=40
        ROMWORD'("01111011111110001000100000101011"),--address=41
        ROMWORD'("01111011110001011110001010001010"),--address=42
        ROMWORD'("01111011100100100000101110000100"),--address=43
        ROMWORD'("01111011010111010000001110011000"),--address=44
        ROMWORD'("01111011001001101100101101001001"),--address=45
        ROMWORD'("01111010111011110110001100011101"),--address=46
        ROMWORD'("01111010101101101100101110011101"),--address=47
        ROMWORD'("01111010011111010000010101010101"),--address=48
        ROMWORD'("01111010010000100001000011010010"),--address=49
        ROMWORD'("01111010000001011110111010100110"),--address=50
        ROMWORD'("01111001110010001001111101100110"),--address=51
        ROMWORD'("01111001100010100010001110101010"),--address=52
        ROMWORD'("01111001010010100111110000001010"),--address=53
        ROMWORD'("01111001000010011010100100100101"),--address=54
        ROMWORD'("01111000110001111010101110011010"),--address=55
        ROMWORD'("01111000100001001000010000001011"),--address=56
        ROMWORD'("01111000010000000011001100100000"),--address=57
        ROMWORD'("01110111111110101011100110000000"),--address=58
        ROMWORD'("01110111101101000001011111010110"),--address=59
        ROMWORD'("01110111011011000100111011010010"),--address=60
        ROMWORD'("01110111001000110101111100100011"),--address=61
        ROMWORD'("01110110110110010100100101111111"),--address=62
        ROMWORD'("01110110100011100000111010011011"),--address=63
        ROMWORD'("01110110010000011010111100110010"),--address=64
        ROMWORD'("01110101111101000010110000000000"),--address=65
        ROMWORD'("01110101101001011000010111000100"),--address=66
        ROMWORD'("01110101010101011011110101000000"),--address=67
        ROMWORD'("01110101000001001101001100111010"),--address=68
        ROMWORD'("01110100101100101100100001111000"),--address=69
        ROMWORD'("01110100010111111001110111000101"),--address=70
        ROMWORD'("01110100000010110101001111101110"),--address=71
        ROMWORD'("01110011101101011110101111000100"),--address=72
        ROMWORD'("01110011010111110110011000011001"),--address=73
        ROMWORD'("01110011000001111100001111000011"),--address=74
        ROMWORD'("01110010101011110000010110011001"),--address=75
        ROMWORD'("01110010010101010010110001110111"),--address=76
        ROMWORD'("01110001111110100011100100111010"),--address=77
        ROMWORD'("01110001100111100010110011000100"),--address=78
        ROMWORD'("01110001010000010000011111110110"),--address=79
        ROMWORD'("01110000111000101100101110110111"),--address=80
        ROMWORD'("01110000100000110111100011101111"),--address=81
        ROMWORD'("01110000001000110001000010001010"),--address=82
        ROMWORD'("01101111110000011001001101110101"),--address=83
        ROMWORD'("01101111010111110000001010100001"),--address=84
        ROMWORD'("01101110111110110101111100000001"),--address=85
        ROMWORD'("01101110100101101010100110001100"),--address=86
        ROMWORD'("01101110001100001110001100111000"),--address=87
        ROMWORD'("01101101110010100000110100000010"),--address=88
        ROMWORD'("01101101011000100010011111101000"),--address=89
        ROMWORD'("01101100111110010011010011101001"),--address=90
        ROMWORD'("01101100100011110011010100001001"),--address=91
        ROMWORD'("01101100001001000010100101001101"),--address=92
        ROMWORD'("01101011101110000001001010111101"),--address=93
        ROMWORD'("01101011010010101111001001100100"),--address=94
        ROMWORD'("01101010110111001100100101010000"),--address=95
        ROMWORD'("01101010011011011001100010001111"),--address=96
        ROMWORD'("01101001111111010110000100110101"),--address=97
        ROMWORD'("01101001100011000010010001010110"),--address=98
        ROMWORD'("01101001000110011110001100001010"),--address=99
        ROMWORD'("01101000101001101001111001101011"),--address=100
        ROMWORD'("01101000001100100101011110010100"),--address=101
        ROMWORD'("01100111101111010000111110100101"),--address=102
        ROMWORD'("01100111010001101100011111000000"),--address=103
        ROMWORD'("01100110110011111000000100001000"),--address=104
        ROMWORD'("01100110010101110011110010100011"),--address=105
        ROMWORD'("01100101110111011111101110111010"),--address=106
        ROMWORD'("01100101011000111011111101111001"),--address=107
        ROMWORD'("01100100111010001000100100001101"),--address=108
        ROMWORD'("01100100011011000101100110100101"),--address=109
        ROMWORD'("01100011111011110011001001110101"),--address=110
        ROMWORD'("01100011011100010001010010110001"),--address=111
        ROMWORD'("01100010111100100000000110010001"),--address=112
        ROMWORD'("01100010011100011111101001001101"),--address=113