小数分频器vhdl实现_verilog 实现小数分频(小数分频器)代码

以下是一个基于VHDL的小数分频器的实现示例：

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.NUMERIC_STD.ALL;

entity fractional_divider is
    Port ( clk : in STD_LOGIC;
           reset : in STD_LOGIC;
           numerator : in unsigned(31 downto 0);
           denominator : in unsigned(31 downto 0);
           frequency : out unsigned(31 downto 0));
end fractional_divider;

architecture Behavioral of fractional_divider is

    signal div_counter : unsigned(31 downto 0) := (others => '0');
    signal phase_accumulator : unsigned(31 downto 0) := (others => '0');
    signal phase_increment : unsigned(31 downto 0) := (others => '0');

begin

    process (reset, clk)
    begin
        if reset = '1' then
            div_counter <= (others => '0');
            phase_accumulator <= (others => '0');
            phase_increment <= (others => '0');
            frequency <= (others => '0');
        elsif rising_edge(clk) then
            div_counter <= div_counter + 1;
            phase_accumulator <= phase_accumulator + phase_increment;
            if div_counter = denominator then
                div_counter <= (others => '0');
                phase_accumulator <= phase_accumulator - denominator;
            end if;
        end if;
    end process;

    phase_increment <= numerator;

    frequency <= phase_accumulator;

end Behavioral;

该代码实现了一个可配置的小数分频器，通过输入分子和分母，输出一个相对于输入时钟频率的分频频率。在时钟上升沿时，该分频器将累加一个相位增量，并在达到特定的相位值时输出一个时钟脉冲。实现中使用了两个计数器，一个用于计算相位累加器中的进位，另一个用于计算输出频率。