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[/] [present/] [trunk/] [Pure/] [rtl/] [vhdl/] [PresentStateMachine.vhd] - Blame information for rev 4

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1 4 gajos
-----------------------------------------------------------------------
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----                                                               ----
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---- Present - a lightweight block cipher project                  ----
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----                                                               ----
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---- This file is part of the Present - a lightweight block        ----
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---- cipher project                                                ----
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---- http://www.http://opencores.org/project,present               ----
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----                                                               ----
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---- Description:                                                  ----
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----     State machine for Present encoder. For more informations  ----
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---- see below.                                                    ----
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---- To Do:                                                        ----
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----                                                               ----
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---- Author(s):                                                    ----
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---- - Krzysztof Gajewski, gajos@opencores.org                     ----
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----                       k.gajewski@gmail.com                    ----
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----                                                               ----
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-----------------------------------------------------------------------
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----                                                               ----
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---- Copyright (C) 2013 Authors and OPENCORES.ORG                  ----
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----                                                               ----
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---- This source file may be used and distributed without          ----
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---- restriction provided that this copyright statement is not     ----
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---- removed from the file and that any derivative work contains   ----
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---- the original copyright notice and the associated disclaimer.  ----
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----                                                               ----
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---- This source file is free software; you can redistribute it    ----
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---- and-or modify it under the terms of the GNU Lesser General    ----
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---- Public License as published by the Free Software Foundation;  ----
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---- either version 2.1 of the License, or (at your option) any    ----
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---- later version.                                                ----
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----                                                               ----
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---- This source is distributed in the hope that it will be        ----
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---- useful, but WITHOUT ANY WARRANTY; without even the implied    ----
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---- warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR       ----
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---- PURPOSE. See the GNU Lesser General Public License for more   ----
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---- details.                                                      ----
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----                                                               ----
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---- You should have received a copy of the GNU Lesser General     ----
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---- Public License along with this source; if not, download it    ----
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---- from http://www.opencores.org/lgpl.shtml                      ----
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----                                                               ----
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-----------------------------------------------------------------------
44 3 gajos
library IEEE;
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use IEEE.STD_LOGIC_1164.ALL;
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use IEEE.STD_LOGIC_ARITH.ALL;
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use IEEE.STD_LOGIC_UNSIGNED.ALL;
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use IEEE.NUMERIC_STD.ALL;
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use work.kody.ALL;
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entity PresentStateMachine is
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        generic (
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                w_5 : integer := 5
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        );
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        port (
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                clk, reset, start : in std_logic;
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                ready, cnt_res, ctrl_mux, RegEn: out std_logic;
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                num : in std_logic_vector (w_5-1 downto 0)
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        );
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end PresentStateMachine;
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architecture Behavioral of PresentStateMachine is
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        signal state : stany;
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        signal next_state : stany;
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        begin
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                States : process(state, start, num)
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                        begin
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                                case state is
71 4 gajos
                                    ---- Waiting for start
72 3 gajos
                                        when NOP =>
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                                                ready <= '0';
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                                                cnt_res <= '0';
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                                                ctrl_mux <= '0';
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                                                RegEn <= '0';
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                                                if (start = '1') then
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                                                        next_state <= SM_START;
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                                                else
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                                                        next_state <= NOP;
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                                                end if;
82 4 gajos
                                        -- Decoding
83 3 gajos
                                        when SM_START =>
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                                                ready <= '0';
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                                                RegEn <= '1';
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                                                cnt_res <= '1';
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                                                if (start = '1') then
88 4 gajos
                                                    -- control during first start
89 3 gajos
                                                        if (num = "00000") then
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                                                                ctrl_mux <= '0';
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                                                                next_state <= SM_START;
92 4 gajos
                                                        -- last iteration
93 3 gajos
                                                        elsif (num = "11111") then
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                                                                ctrl_mux <= '1';
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                                                                next_state <= SM_READY;
96 4 gajos
                                                        -- rest iterations
97 3 gajos
                                                        else
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                                                                ctrl_mux <= '1';
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                                                                next_state <= SM_START;
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                                                        end if;
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                                                else
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                                                        ctrl_mux <= '0';
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                                                        next_state <= NOP;
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                                                end if;
105 4 gajos
                                        -- Decoding end
106 3 gajos
                                        when SM_READY =>
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                                                cnt_res <= '0';
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                                                RegEn <= '0';
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                                                ready <= '1';
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                                                if (start = '1') then
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                                                        ctrl_mux <= '1';
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                                                        next_state <= SM_READY;
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                                                else
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                                                        ctrl_mux <= '0';
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                                                        next_state <= NOP;
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                                                end if;
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                                end case;
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                end process States;
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                SM : process (clk, reset)
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                        begin
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                                if (reset = '1') then
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                                        state <= NOP;
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                                elsif (clk'Event and clk = '1') then
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                                        state <= next_state;
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                                end if;
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                        end process SM;
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        end Behavioral;
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