URL
https://opencores.org/ocsvn/dirac/dirac/trunk
Subversion Repositories dirac
[/] [dirac/] [trunk/] [src/] [common/] [ARITHMETIC_UNIT.vhd] - Rev 10
Go to most recent revision | Compare with Previous | Blame | View Log
-- ***** BEGIN LICENSE BLOCK ***** -- -- $Id: ARITHMETIC_UNIT.vhd,v 1.4 2006-10-05 16:17:11 petebleackley Exp $ $Name: not supported by cvs2svn $ -- * -- * Version: MPL 1.1/GPL 2.0/LGPL 2.1 -- * -- * The contents of this file are subject to the Mozilla Public License -- * Version 1.1 (the "License"); you may not use this file except in compliance -- * with the License. You may obtain a copy of the License at -- * http://www.mozilla.org/MPL/ -- * -- * Software distributed under the License is distributed on an "AS IS" basis, -- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for -- * the specific language governing rights and limitations under the License. -- * -- * The Original Code is BBC Research and Development code. -- * -- * The Initial Developer of the Original Code is the British Broadcasting -- * Corporation. -- * Portions created by the Initial Developer are Copyright (C) 2004. -- * All Rights Reserved. -- * -- * Contributor(s): Peter Bleackley (Original author) -- * -- * Alternatively, the contents of this file may be used under the terms of -- * the GNU General Public License Version 2 (the "GPL"), or the GNU Lesser -- * Public License Version 2.1 (the "LGPL"), in which case the provisions of -- * the GPL or the LGPL are applicable instead of those above. If you wish to -- * allow use of your version of this file only under the terms of the either -- * the GPL or LGPL and not to allow others to use your version of this file -- * under the MPL, indicate your decision by deleting the provisions above -- * and replace them with the notice and other provisions required by the GPL -- * or LGPL. If you do not delete the provisions above, a recipient may use -- * your version of this file under the terms of any one of the MPL, the GPL -- * or the LGPL. -- * ***** END LICENSE BLOCK ***** */ library IEEE; use IEEE.STD_LOGIC_1164.ALL; use IEEE.STD_LOGIC_ARITH.ALL; use IEEE.STD_LOGIC_UNSIGNED.ALL; use IEEE.NUMERIC_STD.ALL; -- Uncomment the following lines to use the declarations that are -- provided for instantiating Xilinx primitive components. --library UNISIM; --use UNISIM.VComponents.all; entity ARITHMETIC_UNIT is Port ( DIFFERENCE : in std_logic_vector(15 downto 0); PROB : in std_logic_vector(7 downto 0); LOW : in std_logic_vector(15 downto 0); ENABLE : in std_logic; RESET : in std_logic; CLOCK : in std_logic; DIFFERENCE_OUT0 : out std_logic_vector(15 downto 0); DIFFERENCE_OUT1 : out std_logic_vector(15 downto 0); RESULT_OUT0 : out std_logic_vector(15 downto 0); RESULT_OUT1 : out std_logic_vector(15 downto 0); DATA_LOAD : out std_logic :='1'); end ARITHMETIC_UNIT; architecture RTL of ARITHMETIC_UNIT is signal LOW2 : std_logic_vector(16 downto 0); signal PRODUCT : std_logic_vector (24 downto 0); signal PRODUCT2 : std_logic_vector (16 downto 0); signal RESULT : std_logic_vector (16 downto 0); signal RESULT0 : std_logic_vector (16 downto 0); signal DIFFERENCE1 : std_logic_vector (16 downto 0); signal DIFFERENCE2 : std_logic_vector(16 downto 0); signal DIFFERENCE3 : std_logic_vector(16 downto 0); signal DIFFERENCE4 : std_logic_vector(16 downto 0); signal DELAY1 : std_logic; -- signal DELAY2 : std_logic; signal CALCULATE : std_logic; begin -- The arithmetic DIFFERENCE2 <= ('0' & DIFFERENCE) + "00000000000000001"; MULTIPLY : process (CLOCK) begin if CLOCK'event and CLOCK = '1' then if ENABLE = '1' then PRODUCT <= DIFFERENCE2 * PROB; end if; end if; end process MULTIPLY; PRODUCT2 <= PRODUCT(24 downto 8); RESULT <= LOW2 + PRODUCT2; RESULT_OUT1 <= RESULT(15 downto 0); RESULT0 <= (RESULT - "00000000000000001"); RESULT_OUT0 <= RESULT0(15 downto 0); DIFFERENCE3 <= (PRODUCT2 - "00000000000000001"); DIFFERENCE4 <= (DIFFERENCE1 - PRODUCT2); DIFFERENCE_OUT1 <= DIFFERENCE4(15 downto 0); DIFFERENCE_OUT0 <= DIFFERENCE3(15 downto 0); -- Control logic CALCULATE <= ENABLE and not RESET; DATA_LOAD <= DELAY1;-- and DELAY2; -- Sequential control logic DELAYS: process (CLOCK) begin if CLOCK'event and CLOCK = '1' then DELAY1 <= CALCULATE; -- DELAY2 <= DELAY1; if ENABLE = '1' then DIFFERENCE1 <= '0' & DIFFERENCE; LOW2 <= '0' & LOW; end if; end if; end process DELAYS; end RTL;
Go to most recent revision | Compare with Previous | Blame | View Log