DHT11 VHDL带注释

下面是DHT11的VHDL代码，带有注释：

-- DHT11 Sensor Interface in VHDL
-- Author: Your Name
-- Date: Date

-- Define the Entity
entity DHT11 is
    Port (
        clk : in std_logic; -- Clock Input
        rst : in std_logic; -- Reset Input
        data : inout std_logic; -- Data Line (Bidirectional)
        temperature : out std_logic_vector(7 downto 0); -- Temperature Output
        humidity : out std_logic_vector(7 downto 0) -- Humidity Output
    );
end entity DHT11;

-- Define the Architecture
architecture Behavioral of DHT11 is

    -- Define Internal Signals
    signal count : integer range 0 to 80 := 0; -- Counter for Timing
    signal bit_count : integer range 0 to 40 := 0; -- Counter for Receiving Bits
    signal data_buffer : std_logic_vector(39 downto 0) := (others => '0'); -- Buffer for Received Data
    signal temperature_buffer : std_logic_vector(7 downto 0) := (others => '0'); -- Buffer for Temperature
    signal humidity_buffer : std_logic_vector(7 downto 0) := (others => '0'); -- Buffer for Humidity

begin

    -- Process for Timing and Receiving Data
    process(clk, rst)
    begin
        if rst = '1' then -- Reset
            count <= 0;
            bit_count <= 0;
            data_buffer <= (others => '0');
            temperature_buffer <= (others => '0');
            humidity_buffer <= (others => '0');
            data <= '1'; -- Set Data Line High
            temperature <= (others => '0');
            humidity <= (others => '0');
        elsif rising_edge(clk) then -- Clock Rising Edge
            if count = 0 then -- Start Signal
                data <= '0'; -- Set Data Line Low
            elsif count = 20 then -- End of Start Signal
                data <= '1'; -- Set Data Line High
            elsif count = 40 then -- Read Data
                if bit_count < 40 then -- Receiving Bits
                    data_buffer(bit_count) <= data; -- Store Received Bit
                    bit_count <= bit_count + 1; -- Increment Bit Counter
                else -- Data Received
                    temperature_buffer <= data_buffer(15 downto 8); -- Extract Temperature
                    humidity_buffer <= data_buffer(31 downto 24); -- Extract Humidity
                    temperature <= temperature_buffer; -- Output Temperature
                    humidity <= humidity_buffer; -- Output Humidity
                    bit_count <= 0; -- Reset Bit Counter
                end if;
            end if;
            count <= count + 1; -- Increment Counter
        end if;
    end process;

end architecture Behavioral;

希望这可以帮助你理解DHT11在VHDL中的实现。