vhdl中具有结构设计的多路复用器

Question

我对VHDL完全陌生，我想实施以下MUX表示逻辑implication S0 => S1不使用其他门。

我想使用结构设计，但是我的主要问题之一是我不了解如何正确映射端口，以便实现给定的含义。

到目前为止，我的代码正在编译并且iSim已启动，但是我收到两个警告：

1. mux41_impl仍然是黑盒子，它没有绑定实体。
2. mux_out_test的值为U

此外，我知道我的组件必须与实体完全匹配但是如果我将其重命名为实体名称，则会收到非法的递归消息。

code

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

entity MUX41_IMPL_top is
port (
    D0, D1, D2, D3, S0, S1: in STD_LOGIC;
    mux_out : out STD_LOGIC
);
end MUX41_IMPL_top;

architecture structure of MUX41_IMPL_top is

component MUX41_IMPL
    port (
        D0, D1, D2, D3, S0, S1: in STD_LOGIC;
        mux_out : out STD_LOGIC
    );
end component;

begin

u1: MUX41_IMPL port map (D0, D1, D2, D3, S0, S1, mux_out);
end structure;

测试台代码

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

entity MUX41_IMPL_SIMBOX is
end MUX41_IMPL_SIMBOX;

architecture TEST_MUX41_IMPL of MUX41_IMPL_SIMBOX is

component MUX41_IMPL is
    port (
        D0, D1, D2, D3, S0, S1: in STD_LOGIC;
        mux_out : out STD_LOGIC
    );
end component;

signal D0_test : STD_LOGIC := '1';
signal D1_test : STD_LOGIC := '0';
signal D2_test : STD_LOGIC := '1';
signal D3_test : STD_LOGIC := '1';
signal S0_test, S1_test : STD_LOGIC := '0';
signal mux_out_test : STD_LOGIC;

for my_MUX41_IMPL : MUX41_IMPL use entity work.MUX41_IMPL_top(structure);

begin
    my_MUX41_IMPL : MUX41_IMPL
    port map (
    D0 => D0_test,
    D1 => D1_test,
    D2 => D2_test,
    D3 => D3_test,
    S0 => S0_test,
    S1 => S1_test,
    mux_out => mux_out_test
    );

    S0_test <= not S0_test after 2 ns;
    S1_test <= not S1_test after 4 ns;

end TEST_MUX41_IMPL;

Answer 1

entity MUX41_IMPL_top is
port (
    D0, D1, D2, D3: in STD_LOGIC;
    Sel : in std_logic_vector(1 downto 0);    
    mux_out : out STD_LOGIC

);
end MUX41_IMPL_top;

architecture structure of MUX41_IMPL_top is
begin

with Sel select
    mux_out <=  D0 when "00",
                D1 when "01",
                D2 when "10",            
                D3 when "11",            
                '0' when others;    

architecture structure;