head 1.3; access; symbols version_1_1:1.3 okinawa_1:1.1.1.1 VSFR_1:1.1.1.1 Vectra:1.1.1; locks; strict; comment @# @; 1.3 date 2005.03.04.08.06.21; author arif_endro; state Exp; branches; next 1.2; 1.2 date 2005.02.21.06.55.04; author arif_endro; state Exp; branches; next 1.1; 1.1 date 2005.01.04.02.05.58; author arif_endro; state Exp; branches 1.1.1.1; next ; 1.1.1.1 date 2005.01.04.02.05.58; author arif_endro; state Exp; branches; next ; desc @@ 1.3 log @*** empty log message *** @ text @-- $Id: sub_12bit.vhdl,v 1.2 2005/02/21 06:55:04 arif_endro Exp $ ------------------------------------------------------------------------------- -- Title : Subtractor 12 bit -- Project : FM Receiver ------------------------------------------------------------------------------- -- File : sub_12bit.vhdl -- Author : "Arif E. Nugroho" -- Created : 2004/12/01 -- Last update : -- Simulators : -- Synthesizers: -- Target : ------------------------------------------------------------------------------- -- Description : Subtractor 12 bit used in loop filter ------------------------------------------------------------------------------- -- Copyright (C) 2004 Arif E. Nugroho -- This VHDL design file is an open design; you can redistribute it and/or -- modify it and/or implement it after contacting the author ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- -- -- THIS SOURCE FILE MAY BE USED AND DISTRIBUTED WITHOUT RESTRICTION -- PROVIDED THAT THIS COPYRIGHT STATEMENT IS NOT REMOVED FROM THE FILE AND THAT -- ANY DERIVATIVE WORK CONTAINS THE ORIGINAL COPYRIGHT NOTICE AND THE -- ASSOCIATED DISCLAIMER. -- ------------------------------------------------------------------------------- -- -- THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR -- IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF -- MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO -- EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, -- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; -- OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, -- WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR -- OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF -- ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -- ------------------------------------------------------------------------------- library IEEE; use IEEE.STD_LOGIC_1164.ALL; entity sub_12bit is port ( addend_12bit : in bit_vector (11 downto 0); subtrahend_12bit : in bit_vector (11 downto 0); subtractor12_output : out bit_vector (11 downto 0) ); end sub_12bit; architecture structural of sub_12bit is component fulladder port ( addend : in bit; augend : in bit; carry_in : in bit; sum : out bit; carry : out bit ); end component; -- internal signal signal c00 : bit; signal c01 : bit; signal c02 : bit; signal c03 : bit; signal c04 : bit; signal c05 : bit; signal c06 : bit; signal c07 : bit; signal c08 : bit; signal c09 : bit; signal c10 : bit; signal c11 : bit; signal c12 : bit; signal augend_12bit : bit_vector (11 downto 0); signal adder12_output : bit_vector (11 downto 0); begin c00 <= '1'; -- add one to get 2's complement -- first complement augend_12bit (11) <= not (subtrahend_12bit (11)); augend_12bit (10) <= not (subtrahend_12bit (10)); augend_12bit (09) <= not (subtrahend_12bit (09)); augend_12bit (08) <= not (subtrahend_12bit (08)); augend_12bit (07) <= not (subtrahend_12bit (07)); augend_12bit (06) <= not (subtrahend_12bit (06)); augend_12bit (05) <= not (subtrahend_12bit (05)); augend_12bit (04) <= not (subtrahend_12bit (04)); augend_12bit (03) <= not (subtrahend_12bit (03)); augend_12bit (02) <= not (subtrahend_12bit (02)); augend_12bit (01) <= not (subtrahend_12bit (01)); augend_12bit (00) <= not (subtrahend_12bit (00)); subtractor12_output <= adder12_output; fa11 : fulladder port map ( addend => addend_12bit(11), augend => augend_12bit(11), carry_in => c11, sum => adder12_output(11), carry => c12 ); fa10 : fulladder port map ( addend => addend_12bit(10), augend => augend_12bit(10), carry_in => c10, sum => adder12_output(10), carry => c11 ); fa09 : fulladder port map ( addend => addend_12bit(09), augend => augend_12bit(09), carry_in => c09, sum => adder12_output(09), carry => c10 ); fa08 : fulladder port map ( addend => addend_12bit(08), augend => augend_12bit(08), carry_in => c08, sum => adder12_output(08), carry => c09 ); fa07 : fulladder port map ( addend => addend_12bit(07), augend => augend_12bit(07), carry_in => c07, sum => adder12_output(07), carry => c08 ); fa06 : fulladder port map ( addend => addend_12bit(06), augend => augend_12bit(06), carry_in => c06, sum => adder12_output(06), carry => c07 ); fa05 : fulladder port map ( addend => addend_12bit(05), augend => augend_12bit(05), carry_in => c05, sum => adder12_output(05), carry => c06 ); fa04 : fulladder port map ( addend => addend_12bit(04), augend => augend_12bit(04), carry_in => c04, sum => adder12_output(04), carry => c05 ); fa03 : fulladder port map ( addend => addend_12bit(03), augend => augend_12bit(03), carry_in => c03, sum => adder12_output(03), carry => c04 ); fa02 : fulladder port map ( addend => addend_12bit(02), augend => augend_12bit(02), carry_in => c02, sum => adder12_output(02), carry => c03 ); fa01 : fulladder port map ( addend => addend_12bit(01), augend => augend_12bit(01), carry_in => c01, sum => adder12_output(01), carry => c02 ); fa00 : fulladder port map ( addend => addend_12bit(00), augend => augend_12bit(00), carry_in => c00, sum => adder12_output(00), carry => c01 ); end structural; @ 1.2 log @Update License @ text @d1 1 a1 1 -- $Id: sub_12bit.vhdl,v 1.1.1.1 2005/01/04 02:05:58 arif_endro Exp $ a43 1 use IEEE.STD_LOGIC_arith.ALL; @ 1.1 log @Initial revision @ text @d1 1 a1 1 -- $Id$ d10 1 a10 1 -- Simulators : Modelsim 6.0 d16 1 a16 1 -- Copyright (c) 2004 Arif E. Nugroho d20 21 @ 1.1.1.1 log @Initial releases @ text @@