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lustrec-tests / vhdl_json / vhdl_files / 2-exportOK / ghdl / ghdl / testsuite / gna / issue301 / packages / pkg_param.vhd @ 2051e520

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--!
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--! Copyright (C) 2011 - 2014 Creonic GmbH
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--!
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--! This file is part of the Creonic Viterbi Decoder, which is distributed
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--! under the terms of the GNU General Public License version 2.
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--!
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--! @file
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--! @brief Parameters
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--! @author Markus Fehrenz
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--! @date 2011/07/01
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--!
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--! @details This is the configuration file of the Viterbi decoder.
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--!          Any changes for parameters should be done here.
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--!          Changing parameters somewhere else may result in a malicious
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--!          behavior.
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--!
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library ieee;
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use ieee.std_logic_1164.all;
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use ieee.numeric_std.all;
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package pkg_param is
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	-----------------------------------
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	-- Convolutional Code Parameters --
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	-----------------------------------
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	--
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	-- Set the number of parity values
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	-- This has to correspond to PARITY_POLYNOMIALS
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	--
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	constant NUMBER_PARITY_BITS : natural := 2;
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	type t_parity is array (NUMBER_PARITY_BITS - 1 downto 0) of natural;
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	--
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	-- Set parity polynoms in decimal notation
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	-- NUMBER_PARITY_BITS has to correspond to the number of elements
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	-- Examples: WiFi : [121,91] or [121,91,101]
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	--           CDMA : [491,369] or [367,435,369] or [501,441,331,315]
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	--           GSM  : [27,19] or [27,21,31]
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	--           DAB  : [91,121,101,91]
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	--           WiMAX: [91,121,117]
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	--
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	constant PARITY_POLYNOMIALS   : t_parity := (121,91);
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	--
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	-- Set a recursive polynomial
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	-- Set to 0 if no recursion is used
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	-- Setting this arbitrary may result in a worse error correction ability
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	--
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	constant FEEDBACK_POLYNOMIAL : natural := 0;
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	-----------------------------
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	-- Architecture Parameters --
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	-----------------------------
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	--
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	-- Set bit width of LLR input
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	-- Recommended values: 3 or 4
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	--
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	constant BW_LLR_INPUT : natural := 4;
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	--
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	-- Set the maximum window length which shall be allowed at runtime.
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	-- Recommended: at least 6 * constraint length
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	--
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	constant MAX_WINDOW_LENGTH : natural := 96;
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	--
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	-- Set to 'true' if distributed RAM shall be used
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	-- Set to 'false' if block RAM shall be used
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	--
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	constant DISTRIBUTED_RAM : boolean := true;
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end package pkg_param;