51 lines
911 B
VHDL
51 lines
911 B
VHDL
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library IEEE;
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use IEEE.STD_LOGIC_1164.ALL;
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entity DigitalFilter is
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generic(
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PHASE_SHIFT : integer := 1
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);
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port(
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clk : in STD_LOGIC;
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input : in STD_LOGIC;
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output : out STD_LOGIC
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);
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end DigitalFilter;
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architecture Behavioral of DigitalFilter is
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signal count : natural range 0 to PHASE_SHIFT := 0;
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signal latch : std_logic := '0';
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begin
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process(clk)
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begin
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if rising_edge(clk) then
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if input = '1' then
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if latch = '0' then
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latch <= '1';
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count <= 0;
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else
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if count < PHASE_SHIFT then
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count <= count + 1;
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else
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output <= '1';
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count <= 0;
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end if;
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end if;
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else
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if latch = '1' then
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latch <= '0';
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count <= 0;
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else
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if count < PHASE_SHIFT then
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count <= count + 1;
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else
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output <= '0';
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count <= 0;
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end if;
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end if;
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end if;
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end if;
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end process;
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end Behavioral;
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