BCD to EXCESS THREE CODE CONVERTER (Dataflow)

library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

entity B_Eccess_three is

    Port ( B3,B2,B1,B0 : in  STD_LOGIC;

           E3,E2,E1,E0 : out  STD_LOGIC);

end B_Eccess_three;

architecture Dataflow of B_Eccess_three is

begin

E3<=(B2 and (B1 or B0)) or B3;
E2<=B2 xor (B1 or B0);
E1<=B1 xnor B0;
E0<=not B0;

end  Dataflow;