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[/] [xmatchpro/] [trunk/] [xmw4-comdec/] [src/] [decode_miss_2.vhd] - Blame information for rev 9

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--This library is free software; you can redistribute it and/or
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--modify it under the terms of the GNU Lesser General Public
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--License as published by the Free Software Foundation; either
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--version 2.1 of the License, or (at your option) any later version.
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--This library is distributed in the hope that it will be useful,
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--but WITHOUT ANY WARRANTY; without even the implied warranty of
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--MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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--Lesser General Public License for more details.
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--You should have received a copy of the GNU Lesser General Public
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--License along with this library; if not, write to the Free Software
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--Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
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-- e_mail : j.l.nunez-yanez@byacom.co.uk
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------------------------------------
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--  ENTITY       = DECODE_MISS    --
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--  version      = 1.0            --
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--  last update  = 25/06/01       --
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--  author       = Jose Nunez     --
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------------------------------------
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-- FUNCTION
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-- decodes the input (Huffman) miss type code to give a mask,
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-- miss length and miss+literal character length
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-- PIN LIST
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-- CODE         = input miss type code (Huffman)
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-- M_LIT_LENGTH = length of miss type code and any required literal characters
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-- SELECT_MOVE  = select a move vector
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-- MASK         = decoded mask
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library ieee,dzx;
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use ieee.std_logic_1164.all;
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entity DECODE_MISS_2 is
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port
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(
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        CODE : in bit_vector(3 downto 0);
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        M_LIT_LENGTH : out bit_vector(5 downto 0);
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        MASK : out bit_vector(4 downto 0)
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);
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end DECODE_MISS_2;
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architecture HUFFMAN of DECODE_MISS_2 is
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begin
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TREE_DEC : process(CODE)
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begin
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case CODE is
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    when "1000" | "1001" | "1010" |"1011" | "1100"  | "1101"  | "1110" | "1111"
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                                => MASK <= "10000";
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                M_LIT_LENGTH <= "000010";
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    when "0100" | "0101"| "0110" | "0111"
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                        =>  MASK <= "11111";
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                    M_LIT_LENGTH <= "100011";
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    when "0010" | "0011"
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                =>  MASK <= "11000";
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                    M_LIT_LENGTH <= "001100";
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    when "0001"
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                                =>  MASK <= "11100";
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                    M_LIT_LENGTH <= "010101";
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    when "0000"
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                =>  MASK <= "11110";
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                    M_LIT_LENGTH <= "011101";
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    when others
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                =>  MASK <= "00000";
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                    M_LIT_LENGTH <= "000000";
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end case;
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end process TREE_DEC;
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end HUFFMAN; -- end of architecture
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