[ASK] top_module

bramka_or:

library ieee;
use ieee.std_logic_1164.all;
entity bramka_or is
    port( x1_or, x2_or: in bit;
            out_or: out bit);
end bramka_or;
architecture struct of bramka_or is
begin
    out_or <= x1_or or x2_or;
end struct;

////////////////////////////////////////////////////////////////////////

bramka_and:

library ieee;
use ieee.std_logic_1164.all;
entity bramka_and is
    port( x1_and, x2_and: in bit;
            out_and: out bit);
end bramka_and;
architecture struct of bramka_and is
begin
    out_and <= x1_and and x2_and;
end struct;

////////////////////////////////////////////////////////////////////////

andor:

library ieee;
use ieee.std_logic_1164.all;
entity andor is
    port( x1_andor, x2_andor, x3_andor: in bit;
            out_andor: out bit);
end andor;
architecture struct of andor is
    component bramka_and is
        port( x1_and, x2_and: in bit;
                out_and: out bit);
    end component;
    component bramka_or is
        port( x1_or, x2_or: in bit;
                out_or: out bit);
    end component;
    signal and_result: bit;
begin
    Gate1: bramka_and port map (x1_and=>x1_andor, x2_and=>x2_andor, out_and=>and_result);
    Gate2: bramka_or port map (x1_or=>and_result, x2_or=>x3_andor, out_or=>out_andor);
end struct;


////////////////////////////////////////////////////////////////////////

top_module:

library ieee;
use ieee.std_logic_1164.all;
entity top_module is
    port( x1_top, x2_top, x3_top, x4_top: in bit;
            out_top: out bit);
end top_module;
architecture struct of top_module is
    component bramka_and is
        port( x1_and, x2_and: in bit;
                out_and: out bit);
    end component;
    component andor is
        port( x1_andor, x2_andor, x3_andor: in bit;
                out_andor: out bit);
    end component;
    signal out_andor1, out_andor2: bit;
begin
    M1: andor port map (x1_top, x2_top, x3_top, out_andor1);
    M2: andor port map (x2_top, x4_top, x1_top, out_andor2);
    Gate1: bramka_and port map (out_andor1, out_andor2, out_top);
end struct;