add_sub_qrb.tdf

基于SIIGX的PCIe的Kit

--lpm_add_sub CARRY_CHAIN="MANUAL" CARRY_CHAIN_LENGTH=48 DEVICE_FAMILY="Stratix II" LPM_DIRECTION="SUB" LPM_WIDTH=4 cin dataa datab
--VERSION_BEGIN 4.1 cbx_cycloneii 2004:05:18:11:27:16:SJ cbx_lpm_add_sub 2004:06:23:12:24:04:SJ cbx_mgl 2004:06:17:17:30:06:SJ cbx_stratix 2004:04:28:15:20:14:SJ cbx_stratixii 2004:05:18:11:28:28:SJ  VERSION_END


--  Copyright (C) 1988-2002 Altera Corporation
--  Any  megafunction  design,  and related netlist (encrypted  or  decrypted),
--  support information,  device programming or simulation file,  and any other
--  associated  documentation or information  provided by  Altera  or a partner
--  under  Altera's   Megafunction   Partnership   Program  may  be  used  only
--  to program  PLD  devices (but not masked  PLD  devices) from  Altera.   Any
--  other  use  of such  megafunction  design,  netlist,  support  information,
--  device programming or simulation file,  or any other  related documentation
--  or information  is prohibited  for  any  other purpose,  including, but not
--  limited to  modification,  reverse engineering,  de-compiling, or use  with
--  any other  silicon devices,  unless such use is  explicitly  licensed under
--  a separate agreement with  Altera  or a megafunction partner.  Title to the
--  intellectual property,  including patents,  copyrights,  trademarks,  trade
--  secrets,  or maskworks,  embodied in any such megafunction design, netlist,
--  support  information,  device programming or simulation file,  or any other
--  related documentation or information provided by  Altera  or a megafunction
--  partner, remains with Altera, the megafunction partner, or their respective
--  licensors. No other licenses, including any licenses needed under any third
--  party's intellectual property, are provided herein.



--synthesis_resources = lut 4 
SUBDESIGN add_sub_qrb
( 
	cin	:	input;
	dataa[3..0]	:	input;
	datab[3..0]	:	input;
	result[3..0]	:	output;
) 
VARIABLE
	result_int[4..0]	:	WIRE;
BEGIN 
	result_int[] = (dataa[], 0) - (datab[], !cin);
	result[] = result_int[4..1];
END;
--VALID FILE