compare unsigned

[Matthias Alles]

Hello,

I have a VHDL-beginner question:

How do I compare an unsigned signal to a value, when I don´t know the
width of this unsigned(the width depends on a parameter)?

At the moment I do it like this:

if to_integer(my_unsigned_value) = 1 then ...

But I have know idea, what the synthesis makes out of this construct (I
guess a comparator with 32 bits).

Can anyone help?

Thanks,
Matthias

 

[Mike Treseler]

Matthias Alles wrote:

At the moment I do it like this:

if to_integer(my_unsigned_value) = 1 then ...

if my_unsigned_value = 1 then ...

will also work for numeric_std.

But I have know idea, what the synthesis makes out of this construct (I
guess a comparator with 32 bits).

Synthesis will use the correct width.
Try it yourself and see.

-- Mike Treseler