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------------------------------------------------------------------------------
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-- This file is a part of the LPP VHDL IP LIBRARY
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-- Copyright (C) 2009 - 2010, Laboratory of Plasmas Physic - CNRS
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--
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-- This program is free software; you can redistribute it and/or modify
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-- it under the terms of the GNU General Public License as published by
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-- the Free Software Foundation; either version 3 of the License, or
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-- (at your option) any later version.
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--
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-- This program 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
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-- GNU General Public License for more details.
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--
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-- You should have received a copy of the GNU General Public License
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-- along with this program; if not, write to the Free Software
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-- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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-------------------------------------------------------------------------------
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library IEEE;
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use IEEE.numeric_std.all;
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use IEEE.std_logic_1164.all;
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--! Generateur de Bauds
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entity BaudGen is
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port(
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clk : in std_logic;
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reset : in std_logic;
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Capture : in std_logic;
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Bclk : out std_logic;
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RXD : in std_logic;
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BTrigger : out std_logic_vector(11 downto 0)
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);
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end BaudGen;
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architecture ar_BaudGen of BaudGen is
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signal cpt : std_logic_vector(11 downto 0) := (others => '0');
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signal errorFlag : std_logic;
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signal triger : std_logic_vector(11 downto 0) := (others => '0');
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signal RX_reg : std_logic:='1';
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begin
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BTrigger <= triger;
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BaudGeneration:
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process(clk,reset)
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begin
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if reset = '0' then
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cpt <= (others => '0');
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triger <= (others => '1');
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errorFlag <= '0';
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elsif clk'event and clk = '1'then
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RX_reg <= RXD;
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if capture = '1' then
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cpt <= (others => '0');
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triger <= (others => '1');
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errorFlag <= '0';
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else
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if RX_reg /= RXD then
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cpt <= (others => '0');
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if cpt = std_logic_vector(TO_UNSIGNED(0,12)) then
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errorFlag <= '1';
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elsif errorFlag = '1' then
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triger <= cpt;
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errorFlag <= '0';
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else
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errorFlag <= '1';
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end if;
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else
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if cpt = triger then
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cpt <= (others => '0');
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errorFlag <= '0';
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else
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cpt <= std_logic_vector(unsigned(cpt) + 1);
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end if;
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end if;
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end if;
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end if;
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end process;
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process(clk)
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begin
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if clk'event and clk = '1' then
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if cpt = std_logic_vector(TO_UNSIGNED(0,12)) then
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Bclk <= '0';
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elsif cpt = '0' & triger(11 downto 1) then
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Bclk <= '1';
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end if;
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end if;
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end process;
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end ar_BaudGen;
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