Question regarding transition coverage

[Dharak Shah]

Hi,

I have a query for transition coverage.

My Requirement:

I have some valid values for particular coverpoints.

-----------------------------------------------------------

covergroup covergrp_1;

coverpoint_1 : coverpoint var_1

{

bins var_bin[] = {[8'h1:8'hFF]};

}

endgroup

-----------------------------------------------------------

Now I want transition coverage for following condition.

- Transition for different values.

e.g. 1=>2, 1=>3 .... 1=>FF

2=>1, 2=>3 .... 2=>FF

But same transition is not valid. I want to ignore those.

e.g. 1=>1 2=>2 ,3=>3 .... FF=>FF (ignore these)

My Code:

-----------------------------------------------------------

covergroup covergrp_1;

coverpoint_1 : coverpoint var_1

{

bins var_bin[] = {[8'h1:8'hFF]};

}

coverpoint_trans : coverpoint var_1

{

bins trans_bin[] = ([8'h1:8'hFF]=>[8'h1:8'hFF]);

ignore_bins ignore_trans = ([8'h1:8'hFF] [*2]);

}

endgroup

-----------------------------------------------------------

But somehow it seems to be not working..

Any inputs?