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--:file: Entity.vhd
library IEEE;
context IEEE.IEEE_std_context;
entity Reproducer is
generic (
g_Precision : natural := 11;
g_PulsesPerRevolution : natural := 1000
);
port (
CLK : in std_logic;
RST : in std_logic;
EN : in std_logic;
Z : in std_logic;
POS : out unsigned(g_Precision-1 downto 0)
);
end entity;
architecture arch of Reproducer is
signal Position : unsigned(POS'range);
signal Direction : std_logic := '0';
begin
PositionCounter: process(RST, Z, CLK)
constant CountLimit : unsigned(Position'range) := to_unsigned(4*g_PulsesPerRevolution-1, Position);
begin
if RST or Z then
Position <= (others => '0');
elsif rising_edge(CLK) and EN='1' then
Position <=
(others=>'0') when Position = CountLimit and Direction='1' else
CountLimit when Position = 0 and Direction='0' else
Position+1 when Direction else
Position-1;
end if;
end process;
pos <= position;
direction <= '0';
end architecture;
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