简单的VHDL 4对1 MUX测试台已挂

Question

  -----------begin part1.vhdl---------------------


library ieee;
use ieee.std_logic_1164.all;

entity part1 is
    generic ( width : integer :=7);
    PORT( a, b, c, d: IN std_logic_vector(width downto 0);
        sel: IN std_logic_vector(1 downto 0);
        result: OUT std_logic_vector(width downto 0)
    );
end part1;

architecture muxbehav of part1 is

BEGIN

    result <=       a after 5 ns when sel="00" else
                    b after 5 ns when sel="01" else
                    c after 5 ns when sel="10" else
                    d after 5 ns;
end muxbehav;

-----------end part1.vhdl---------------------

    -----------begin part1_tb.vhdl------------------

library ieee;
use ieee.std_logic_1164.all;


entity part1_tb is
    generic( width : integer := 7);
end part1_tb;

architecture tb of part1_tb is

    signal t_a: std_logic_vector(width downto 0):="00000000";
    signal t_b: std_logic_vector(width downto 0):="00000000";
    signal t_c: std_logic_vector(width downto 0):="00000000";
    signal t_d: std_logic_vector(width downto 0):="00000000";
    signal t_s: std_logic_vector(1 downto 0);
    signal t_o: std_logic_vector(width downto 0);

component part1
    generic(width : integer);
    PORT( a, b, c, d: IN std_logic_vector(width downto 0);
        sel: IN std_logic_vector(1 downto 0);
        result: OUT std_logic_vector(width downto 0)
    );
    end component;

    begin

    U_part1: part1 generic map(width) port map(a=>t_a, b=>t_b, c=>t_c, d=>t_d, sel=>t_s, result=>t_o);

    process

        begin

        t_a <= "11111111";
        t_b <= "00000001";
        t_c <= "10101010";
        t_d <= "01010101";

        wait for 10 ns;
        t_s <= "00";
        wait for 6 ns;
        assert (t_o="11111111") report "Error input a" severity error;

        wait for 10 ns;
        t_s <= "01";
        wait for 6 ns;
        assert (t_o="00000001") report "Error input b" severity error;

        wait for 10 ns;
        t_s <= "10";
        wait for 6 ns;
        assert (t_o="10101010") report "Error input c" severity error;

        wait for 10 ns;
        t_s <= "11";
        wait for 6 ns;
        assert (t_o="01010101") report "Error input d" severity error;

        wait;

    end process;
end tb;

-----------end part1_tb.vhdl------------------

您好，这是我用 VHDL 编写的第一个代码。它是一个简单的 4 比 1 多路复用器，可以接收任意宽度的向量。然而，当我尝试运行我的测试平台时，GHDL 只是挂起。我看过与我的类似的测试平台，但我仍然找不到我的测试平台挂起的原因。有什么想法吗？

Answer 1

嗯。我看不出有什么理由让它挂起。

我刚刚在 Ubuntu 10.04 上的 ghdl0.29 中尝试了你的代码 - 对我来说工作得很好（因为它退出时没有打印任何消息，所以看起来你的代码有效:) gtkwave 中的波浪看起来也很有说服力。

您可以尝试删除您的 work 文件夹和可执行文件并重新编译吗？

抱歉，这并不是真正能让您前进的答案！