altshift.tdf

用s3c44b0x和 CIS（ContactImage Sensor) 传感器接口

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--
--	ALTSHIFT Parameterized Megafunction
--
--	Copyright (C) 1988-2000 Altera Corporation
--	Any megafunction design, and related net list (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, net list, 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,
--	net list, 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.
--
--	Version 2.0
--
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PARAMETERS
(
	WIDTH = 4,
	DEPTH = 0
);

SUBDESIGN altshift
(
	data[(WIDTH - 1)..0]	: INPUT;
	clock					: INPUT = GND;
	aclr					: INPUT = GND;
	clken					: INPUT = VCC;
	result[(WIDTH - 1) ..0]	: OUTPUT;
)
VARIABLE
	IF DEPTH > 0 GENERATE
		points[(DEPTH - 1)..0][(WIDTH - 1)..0]	: DFFE;
	END GENERATE;
BEGIN
	IF DEPTH == 0 GENERATE
		result[] = data[]; 
	ELSE GENERATE
		points[][].clk = clock;
		points[][].clrn = !aclr;
		
		IF USED(clken) GENERATE
			points[][].ena = clken;
		END GENERATE;
		
		points[0][].d = data[];
		IF DEPTH > 1 GENERATE
			FOR row IN 1 TO DEPTH - 1 GENERATE
				points[row][].d = points[row - 1][].q;
			END GENERATE;
		END GENERATE;
		result[] = points[DEPTH - 1][].q;
	END GENERATE;
END;