----------------------------------------------------------
-- keySense
-- Author   : Gautam Karnik
-- Date     : March 30, 2001
-- Filename : keySense.vhd
-- Architecture : Behavioral
-- Description  : This entity takes the input lines from 
--                the keypad and determines when there is
--                activity by simply "ANDing" all of the
--                input lines together.
----------------------------------------------------------
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all; 
use ieee.std_logic_unsigned.all; 
library work;
use work.CDMA_pkg.all;

entity keySense is
	generic ( datawidth : positive := 4 );
	port (
		clock, resetn : in std_logic;
		row   : in std_logic_vector  ( datawidth-1 downto 0 );
		sense : out std_logic
	);
end entity keySense;

architecture behavioral of keySense is 
begin

synchronize_sensor : process (clock) is
	begin 
		wait until clock'event and clock = '1';
		if resetn = '0' then
			sense <= '1';
		else
			sense <= (row(0) and row(1)) and (row(2) and row(3));
		end if;
	end process synchronize_sensor;

end behavioral;