quartus 设计计算模块：根据不同的计算要求，设计对应的计算模块，例如加法器、乘法器、逻辑单元的vhdl代码

以下是一些常见计算模块的VHDL代码示例：

1. 全加器（Full Adder）：

entity full_adder is
    port(a, b, c_in : in std_logic;
         s, c_out    : out std_logic);
end entity full_adder;

architecture behavioral of full_adder is
begin
    s <= a xor b xor c_in;
    c_out <= (a and b) or (c_in and (a xor b));
end architecture behavioral;

2. 4位加法器（4-bit Adder）：

entity adder4bit is
    port(a, b     : in  std_logic_vector(3 downto 0);
         carry_in : in  std_logic;
         sum      : out std_logic_vector(3 downto 0);
         carry_out: out std_logic);
end entity adder4bit;

architecture behavioral of adder4bit is
    signal c1, c2, c3 : std_logic;
begin
    fa1: entity work.full_adder port map(a(0), b(0), carry_in, sum(0), c1);
    fa2: entity work.full_adder port map(a(1), b(1), c1, sum(1), c2);
    fa3: entity work.full_adder port map(a(2), b(2), c2, sum(2), c3);
    fa4: entity work.full_adder port map(a(3), b(3), c3, sum(3), carry_out);
end architecture behavioral;

3. 乘法器（Multiplier）：

entity multiplier is
    port(a, b     : in  std_logic_vector(7 downto 0);
         product  : out std_logic_vector(15 downto 0));
end entity multiplier;

architecture behavioral of multiplier is
begin
    product <= (others => '0');
    process(a, b)
    begin
        for i in 0 to 7 loop
            if a(i) = '1' then
                product(i to i+7) <= std_logic_vector(unsigned(product(i to i+7)) + unsigned(b));
            end if;
        end loop;
    end process;
end architecture behavioral;

4. 逻辑单元（Logic Unit）：

entity logic_unit is
    port(a, b     : in  std_logic_vector(3 downto 0);
         sel      : in  std_logic_vector(1 downto 0);
         output   : out std_logic_vector(3 downto 0));
end entity logic_unit;

architecture behavioral of logic_unit is
begin
    with sel select
        output <=  a and b,
                   a or b,
                   a xor b,
                   not a;
end architecture behavioral;

这些示例代码只是简单的示范，实际中还需要考虑时序、延迟、测试等方面的问题。