case3.vhd

DA算法中的使用的查找表模块

LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL;
ENTITY case3  IS
PORT ( table_in:in std_logic_vector(3 downto 0);
       table_out:out integer range -550 to 200);
END case3;
ARCHITECTURE behave OF case3 IS
BEGIN
  PROCESS (table_in)
    BEGIN
      case table_in is
           when "0000"=>table_out<=0;
           when "0001"=>table_out<=-196;
           when "0010"=>table_out<=-213;
           when "0011"=>table_out<=-409;
           when "0100"=>table_out<=-109;
           when "0101"=>table_out<=-305;
           when "0110"=>table_out<=-322;
           when "0111"=>table_out<=-518;
           when "1000"=>table_out<=147;
           when "1001"=>table_out<=-49;
           when "1010"=>table_out<=-66;
           when "1011"=>table_out<=-262;
           when "1100"=>table_out<=38;
           when "1101"=>table_out<=-158;
           when "1110"=>table_out<=-175;
           when "1111"=>table_out<=-371;
           when others=>table_out<=0;

      end case;
  END PROCESS;
END behave;