Digital-Test/vhdl/todo.vhd
2023-08-24 11:58:55 +08:00

75 lines
2.3 KiB
VHDL

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.numeric_std.all;
entity todo is
generic(
INBYLEVEL : boolean:=FALSE
);
port (
clk_i : in std_logic;
data_i : in std_logic_vector(7 downto 0);
data_o : out std_logic_vector(7 downto 0)
);
end todo;
architecture rtl of todo is
type mem_type is array (0 to 255) of integer;
signal mem : mem_type;
signal int : integer;
signal uns : unsigned(7 downto 0);
constant BYTES : positive:=4;
constant WIDTH : positive:=BYTES*8;
signal index : natural range 0 to BYTES-1;
signal comma : std_logic_vector(BYTES*3-1 downto 0);
-- (others => (others => '0')) must be replaced by an initial block with a for
-- or something similar.
--type ff_array is array (0 to 255) of std_logic_vector(7 downto 0);
--signal data_r : ff_array :=(others => (others => '0'));
begin
--**************************************************************************
-- Wrong translations
--**************************************************************************
--
test_i: process(clk_i)
-- iverilog: variable declaration assignments are only allowed at the module level.
variable i : integer:=8;
begin
for i in 0 to 7 loop
if i=4 then
exit; -- iverilog: error: malformed statement
end if;
end loop;
end process test_i;
-- indexed part-select not applied
do_boundary: process (clk_i)
begin
if rising_edge(clk_i) then
for i in 0 to BYTES-1 loop
if comma(BYTES*2+i-1 downto BYTES+i)=comma(3 downto 0) then
index <= i;
end if;
end loop;
end if;
end process;
comma <= comma(BYTES+index-1 downto index);
--**************************************************************************
-- Translations which abort with syntax error (uncomment to test)
--**************************************************************************
-- Concatenation in port assignament fail
-- uns <= "0000" & X"1"; -- It is supported
-- dut1_i: entity work.signextend
-- port map (
-- i => "00000000" & X"11", -- But here fail
-- o => open
-- );
-- Unsupported generate with boolean?
-- in_by_level:
-- if INBYLEVEL generate
-- int <= 9;
-- end generate in_by_level;
end rtl;