串行序列信号接收器VHDL

下面是一个基本的串行序列信号接收器的VHDL代码示例：

library IEEE;
use IEEE.std_logic_1164.all;

entity Serial_Receiver is
    port(
        SCL : in std_logic;
        SDA : in std_logic;
        D7_D0 : in std_logic_vector(7 downto 0);
        LD15 : out std_logic;
        DISP : out std_logic_vector(3 downto 0)
    );
end Serial_Receiver;

architecture Behavioral of Serial_Receiver is
    signal data_in : std_logic_vector(7 downto 0) := "00000000";
    signal address : std_logic_vector(2 downto 0) := "000";
    signal data_out : std_logic_vector(3 downto 0) := "0000";
begin
    LD15 <= D7_D0(7); // 将D7的值显示在LD15上

    process(SCL, SDA, D7_D0)
    begin
        if rising_edge(SCL) then // 判断是否处于SCL上升沿
            if SDA = '0' then // 判断是否为起始信号
                data_in <= "00000000";
            elsif SDA = '1' then // 判断是否为高电平信号
                data_in <= data_in(6 downto 0) & D7_D0(0); // 将D0存储到data_in的最低位
                if D7_D0(7) = '1' then // 判断是否需要显示
                    address <= D7_D0(6 downto 4); // 获取地址
                    case address is
                        when "000" => data_out <= data_in(3 downto 0);
                        when "001" => data_out <= data_in(7 downto 4);
                        when "010" => data_out <= data_in(1 downto 0) & data_in(7 downto 2);
                        when "011" => data_out <= data_in(5 downto 2) & data_in(0);
                        when "100" => data_out <= data_in(6 downto 0);
                        when "101" => data_out <= data_in(2 downto 0) & data_in(7) & data_in(5 downto 3);
                        when "110" => data_out <= data_in(4 downto 0);
                        when "111" => data_out <= data_in(7 downto 5) & data_in(2 downto 1);
                        when others => null;
                    end case;
                    DISP <= data_out;
                end if;
            end if;
        end if;
    end process;
end Behavioral;

这个代码实现了输入SCL和SDA信号，以及D7-D0的值，根据D7-D0的值在相应的数码管上显示数值，并在LD15上显示D7的值。其中，根据D6-D4的值，将数据显示在相应的数码管上，并将D3-D0的值转换为十六进制数。需要注意的是，这只是一个基本的示例，具体实现方式需要根据实际情况进行修改和优化。