VHDL code for Gray to Binary Code Converter

Binary code equivalent of the given gray number is computed as follows:

b₃ = g₃
b₂ = b₃ ⊕ g₂
b₁ = b₂ ⊕ g₁
b₀ = b₁ ⊕ g₀

library ieee;
use ieee.std_logic_1164.all;


entity gtb_vhd is
  port (
    g :in  std_logic_vector(3 downto 0);
    b :inout std_logic_vector(3 downto 0));
  
end gtb_vhd;


architecture gtb_vhd_ar of gtb_vhd is


begin  -- gtb_vhd_ar


  b(3)<=g(3);
  b(2)<=b(3) xor g(2);
  b(1)<=b(2) xor g(1);
  b(0)<=b(1) xor g(0);


end gtb_vhd_ar;