Passing Generics to Record Port Types
Can you use type generics with Quartus?
Then you leave the type completely unspecified, so that you can create a FIFO of integers
or any other data type:
package fifo_pkg is
generic (type element_type);
type fifo_in_type is record
data_in : element_type;
rd : std_logic;
wr : std_logic;
end record;
type fifo_out_type is record
data_out : element_type;
empty : std_logic;
full : std_logic;
end record;
component fifo is
generic
(
MIN_DEPTH : integer;
DATA_WIDTH : integer
);
port
(
clk : in std_logic;
res_n : in std_logic;
i : in fifo_in_type;
o : out fifo_out_type
);
end component fifo;
end fifo_pkg;
Then when you want to use it:
package wide_fifo_pkg is new fifo_pkg
generic map (type => std_logic_vector(31 downto 0));
and then you can use fifo_in_type
and fifo_out_type
:
signal i : fifo_in_type;
If you have more than one FIFO in a design unit you can create several versions of the package and use the package prefix to get the right type:
package narrow_fifo_pkg is new fifo_pkg
generic map (type => std_logic_vector(3 downto 0));
signal i32 : wide_fifo_pkg.fifo_in_type;
signal i4 : narrow_fifo_pkg.fifo_in_type;
Another VHDL 2008 option: you can have an unconstrained record type:
type fifo_in_type is record
data_in : std_logic_vector;
rd : std_logic;
wr : std_logic;
end record;
which you can then create subtype
s of for your various uses:
subtype fifo1_data_type is fifo_in_type(data_in(31 downto 0));
subtype fifo2_data_type is fifo_in_type(data_in(15 downto 0));
No idea if Quartus supports either of those options - please let us know!