SEQUENCE GENERATOR (Behavioral) , To count the sequence 4,5,3,2,4,5,3. . . .

library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

use IEEE.STD_LOGIC_unsigned.ALL;

entity sg is

    Port ( clk,clr,pr : in  STD_LOGIC;

           q : inout  STD_LOGIC_VECTOR (3 downto 0));

end sg;

architecture Behavioral of sg is

begin

process(clk,clr,pr)

begin

if pr='0' then q<="1111";

elsif clr='0' then q<="0000";

elsif clk='0' and clk'event then

if q="0000" then q<="0100";
elsif q="1111" then q<="0001";

elsif q="0100" then q<="0101";

elsif q="0101" then q<="0011";

elsif q="0011" then q<="0010";

elsif q="0010" then q<="0100";

end if;

end if;

end process;

end Behavioral;