-------------------------------------------------------------------------------
-- File: irlesser.vhd
--
-- Project: DPF
-- Date: 3/4/02
--
-- Purpose: N-bit comparitor, if the value of dataA is 
--			less than the value of dataB the ouput is set to '1'
--
--			Modified from the megafunction provided by altera 
--
-- Inputs:  	dataA		-- input A
--				dataB		-- input B
--				
--
-- Outputs:    	AleB       -- return from the comparision 
--						   -- valid if A <= B
-- External Connections:
--      		
-------------------------------------------------------------------------------
LIBRARY ieee;
USE ieee.std_logic_1164.all;

ENTITY irlesser IS
	generic(compareWidth : positive := 8);
	PORT
	(
		dataA		: IN STD_LOGIC_VECTOR (compareWidth-1 DOWNTO 0);
		dataB		: IN STD_LOGIC_VECTOR (compareWidth-1 DOWNTO 0);
		AleB		: OUT STD_LOGIC 
	);
END irlesser;


ARCHITECTURE SYN OF irlesser IS

component lpm_compare
	generic(
				lpm_width		: NATURAL;
				one_input_is_constant		: STRING;
				lpm_representation		: STRING
			);
	port(
			dataa	: IN STD_LOGIC_VECTOR (compareWidth-1 DOWNTO 0);
			datab	: IN STD_LOGIC_VECTOR (compareWidth-1 DOWNTO 0);
			AleB	: OUT STD_LOGIC 
		);
end component;

signal compareValue	: STD_LOGIC ;

begin
	AleB    <= compareValue;

	lpm_compare_component : lpm_compare
	GENERIC MAP (
		LPM_WIDTH => compareWidth,
		ONE_INPUT_IS_CONSTANT => "NO",
		LPM_REPRESENTATION => "UNSIGNED"
	)
	PORT MAP (
		dataa => dataa,
		datab => datab,
		AleB => compareValue
	);
END SYN;