基于VHDL语言的六路抢答器。 具体要求： 1、 设计抢答器组数最多为6组，每组的序号分别为1，2，3，4，5，6，启动后方可抢答，按键后组号在LED显示器上显示，同时封锁其他组的按键信号。 2、 设置抢答开启控制键，数字抢答器定时为20秒，通过按键启动抢答器后要求20秒倒计时器开始工作。 3、 抢答者在20秒内进行抢答，则有效；若在20秒定时到达时，仍无抢答者则定时器自动清零。 4、 具有计分功能，每组每答对一题计10分。

以下是一个基于VHDL语言的六路抢答器的设计：

library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;

entity six_way_buzzer is
    port (
        buzzer_start : in std_logic;
        buzzer_1 : in std_logic;
        buzzer_2 : in std_logic;
        buzzer_3 : in std_logic;
        buzzer_4 : in std_logic;
        buzzer_5 : in std_logic;
        buzzer_6 : in std_logic;
        buzzer_reset : in std_logic;
        buzzer_timer : out std_logic;
        buzzer_led : out std_logic_vector(2 downto 0);
        buzzer_score : out std_logic_vector(2 downto 0)
    );
end six_way_buzzer;

architecture behavioral of six_way_buzzer is
    signal buzzer_active : std_logic_vector(5 downto 0) := (others => '0');
    signal buzzer_locked : std_logic_vector(5 downto 0) := (others => '0');
    signal buzzer_count : unsigned(4 downto 0) := (others => '0');
    signal buzzer_timeout : std_logic := '0';
    signal buzzer_timer_running : std_logic := '0';
    signal buzzer_reset_latched : std_logic := '0';
    signal buzzer_score_internal : unsigned(2 downto 0) := (others => '0');
    
begin

    process(buzzer_start, buzzer_reset, buzzer_timer_running, buzzer_timeout, buzzer_count)
    begin
        if buzzer_reset_latched = '1' then
            buzzer_count <= (others => '0');
            buzzer_timeout <= '0';
            buzzer_timer_running <= '0';
            buzzer_reset_latched <= '0';
        elsif buzzer_start = '1' then
            buzzer_timeout <= '0';
            buzzer_count <= (others => '0');
            buzzer_timer_running <= '1';
        elsif buzzer_timer_running = '1' and buzzer_count = 20 then
            buzzer_timeout <= '1';
            buzzer_timer_running <= '0';
            buzzer_count <= (others => '0');
        elsif buzzer_timer_running = '1' and buzzer_count < 20 then
            buzzer_count <= buzzer_count + 1;
        end if;
    end process;
    
    process(buzzer_1, buzzer_2, buzzer_3, buzzer_4, buzzer_5, buzzer_6, buzzer_locked, buzzer_active, buzzer_timeout)
    begin
        buzzer_led <= buzzer_active;
        buzzer_score <= std_logic_vector(buzzer_score_internal);
        
        if buzzer_reset = '1' then
            buzzer_active <= (others => '0');
            buzzer_locked <= (others => '0');
            buzzer_score_internal <= (others => '0');
        else
            if buzzer_active /= (others => '0') and buzzer_timeout = '1' then
                buzzer_score_internal(to_integer(unsigned(buzzer_active))) <= buzzer_score_internal(to_integer(unsigned(buzzer_active))) + 1;
                buzzer_active(to_integer(unsigned(buzzer_active))) <= '0';
            end if;
            
            if buzzer_1 = '1' and buzzer_locked(0) = '0' and buzzer_active /= "100000" then
                buzzer_active <= "100000";
                buzzer_locked <= "100000";
            elsif buzzer_2 = '1' and buzzer_locked(1) = '0' and buzzer_active /= "010000" then
                buzzer_active <= "010000";
                buzzer_locked <= "010000";
            elsif buzzer_3 = '1' and buzzer_locked(2) = '0' and buzzer_active /= "001000" then
                buzzer_active <= "001000";
                buzzer_locked <= "001000";
            elsif buzzer_4 = '1' and buzzer_locked(3) = '0' and buzzer_active /= "000100" then
                buzzer_active <= "000100";
                buzzer_locked <= "000100";
            elsif buzzer_5 = '1' and buzzer_locked(4) = '0' and buzzer_active /= "000010" then
                buzzer_active <= "000010";
                buzzer_locked <= "000010";
            elsif buzzer_6 = '1' and buzzer_locked(5) = '0' and buzzer_active /= "000001" then
                buzzer_active <= "000001";
                buzzer_locked <= "000001";
            end if;
        end if;
    end process;
    
    process(buzzer_reset)
    begin
        if buzzer_reset = '1' then
            buzzer_reset_latched <= '1';
        end if;
    end process;

    buzzer_timer <= buzzer_timer_running and not buzzer_timeout;
    
end behavioral;

该设计包括一个计数器和一个状态机，用于控制抢答器的启动和停止。计数器用于定时20秒，而状态机用于存储哪个抢答器已经被激活和哪些抢答器被锁定了。在抢答器被激活后，该状态机将防止其他抢答器被激活，直到抢答器被重置。此外，该设计还包括一个计分器，用于跟踪每个组的得分。