Using 'ref' with variables in interface

In reply to dave_59:

Hi Dave,

I copy pasted and simulated the above code and I get the same error
message “Invalid ref argument usage as the actual argument is not a variable”
on both vitf.A and vitf.B.

Which simulator did you use? I’m using ncsim (ver 10.2),
I’m not sure if this is a simulator issue???

Thanks for your quick responses,
Babu