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library ieee;
use ieee.std_logic_1164.all;
entity arr02 is
port (
a : std_logic_vector (31 downto 0);
sel : natural range 0 to 3;
clk : std_logic;
res : out std_logic_vector (3 downto 0));
end arr02;
architecture behav of arr02 is
type t_mem is array (0 to 3) of std_logic_vector (7 downto 0);
type t_stage is record
sel : natural range 0 to 3;
val : t_mem;
end record;
signal s : t_stage;
begin
process (clk) is
begin
if rising_edge (clk) then
s.sel <= sel;
s.val <= (a (31 downto 24),
a (23 downto 16),
a (15 downto 8),
a (7 downto 0));
end if;
end process;
process (clk) is
begin
if rising_edge (clk) then
res <= s.val (s.sel)(3 downto 0);
end if;
end process;
end behav;
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