connecting std_logic inout ports and std_logic_vector inout port

[=?ISO-8859-15?Q?Fr=E9d=E9ric_Lochon?=]

Hi,

I'm looking for a (nice) way to connect std_logic_vector and several
std_logic in order to avoid modifying UCF files in ISE.

My simplified problem:
I have a top entity with two "inout" ports (let's say Data_0 and Data_1)
with type std_logic.
I want to map these two signals on an "inout" port of a component with
type std_logic_vector(1 downto 0).

My first idea was to use an alias, but I can't make it work. I tried
several ways:
- alias Data : std_logic_vector(1 downto 0) is (Data_0, Data_1);
- alias Data : std_logic_vector(1 downto 0) is (Data_0 & Data_1);
- alias Data : std_logic_vector(1 downto 0) is Data_0, Data_1;
- alias Data : std_logic_vector(1 downto 0) is Data_0 & Data_1;
ISE gives me an error in every case.

My second idea was to map directly.
port map ( Data => Data_0 & Data_1);
But ISE doesn't want to do that with inout ports.


For now, I'm lacking of ideas because I would really appreciate to solve
this issue without modifying my top entity.

Thanks in advance.

 

[Duane Clark]

My second idea was to map directly.
port map ( Data => Data_0 & Data_1);

port map ( Data(0) => Data_0, Data(1) => Data_1 );

 

[Tricky]

port map ( Data(0) => Data_0, Data(1) => Data_1 );

Or, maybe less elegent in the top level entity

signal temp_data : std_logic_vector(1 downto 0);
begin

temp_data <= data_1 & data_0;

--port map
data => temp_data,

 

[KJ]

Or, maybe less elegent in the top level entity

signal temp_data : std_logic_vector(1 downto 0);
begin

temp_data <= data_1 & data_0;

--port map
data => temp_data,

What you've suggested will only work if 'Data' is an input to the entity.

A similar (but reversed) approach of defining a temporary vector would work
if 'Data' was an output.

No such trick that I know of will work if 'Data' is an inout...mapping each
bit as Duane suggested will work in all situations.

KJ