library IEEE;
use IEEE.STD_LOGIC_1164.all;
entity decoder1 is
port(
a : in STD_LOGIC_VECTOR(1 downto 0);
b : out STD_LOGIC_VECTOR(3 downto 0)
);
end decoder1;
architecture bhv of decoder1 is
begin
process(a)
begin
if (a="00") then
b <= "0001";
elsif (a="01") then
b <= "0010";
elsif (a="10") then
b <= "0100";
else
b <= "1000";
end if;
end process;
end bhv;