One Signal Two Names

If I have a bus --> xyz(31 downto 0) is there a way to assign another name
such that it references xyz(20 downto 10)?

Thanks,
Joel

Weddick

Weddick wrote:
> If I have a bus --> xyz(31 downto 0) is there a way to assign another name
> such that it references xyz(20 downto 10)?

You could use an alias for this.
The downside is that aliases are not visible in simulation.

You could declare variables (or signals) for the fields.

variable left_v : unsigned(10 downto 0);
variable mid_v : unsigned(10 downto 0);
variable left_v : unsigned( 9 downto 0);

and use these to assign to the bus:

bus <= left_v & mid_v & left_v;

-- Mike Treseler

Mike Treseler

Mike Treseler wrote:

> variable left_v : unsigned( 9 downto 0);
_right_v_

> and use these to assign to the bus:
> bus <= left_v & mid_v & left_v;
_right_v_

Mike Treseler

Thanks Mike,

Looks like alias would do the trick if it would work in simulation also.

Joel


"Mike Treseler" <> wrote in message
news:...
> Weddick wrote:
>> If I have a bus --> xyz(31 downto 0) is there a way to assign another
>> name such that it references xyz(20 downto 10)?
>
> You could use an alias for this.
> The downside is that aliases are not visible in simulation.
>
> You could declare variables (or signals) for the fields.
>
> variable left_v : unsigned(10 downto 0);
> variable mid_v : unsigned(10 downto 0);
> variable left_v : unsigned( 9 downto 0);
>
> and use these to assign to the bus:
>
> bus <= left_v & mid_v & left_v;
>
> -- Mike Treseler

Weddick

Mike,
What exactly do you mean by:
> You could use an alias for this.
> The downside is that aliases are not visible in simulation.

Since alias doesn't create new objects, tools are not able to display them
in Waveforms?

Thanks
Srini

Srinivasan Venkataramanan

Srinivasan Venkataramanan wrote:

> Since alias doesn't create new objects, tools are not able to display them
> in Waveforms?

Last time I tried this in modelsim, I could see the
base variable but not the alias slice.

Declared objects are always visible in sim.

-- Mike Treseler

Mike Treseler