help in sintax for various inputs to single internal signal vector binary and decimal

Thank you, i decide my data, leave it in one internal signal of 8 bits, now read about UART examples.

library ieee;

use ieee.std_logic_1164.all;

use ieee.numeric_std.all;

entity joystick is

port

(d1,d2,d3,d4,d5,d6,d7,d8 : in std_logic);

--deci : out integer range 0 to 255

end joystick;

architecture lectura of joystick is

signal val_bin : std_logic_vector(7 downto 0);

signal deci : integer range 0 to 255;

begin

val_bin <= d8 & d7 & d6 & d5 & d4 & d3 & d2 & d1;

deci <= to_integer(unsigned(val_bin));

end lectura;