Sorry for my confusing post.
What I mean, all variables were created with the same bit number. I tested with 15, 16 and 17 bits, I have the same problem.
For a gived value, I was a compilation problem. For another value (same bit number) i have a compilation problem.
pletz (
http://www.alteraforum.com/forum/member.php?u=1380) => sorry I mixed two test programms for my example.
To resume : for the 80Hz value the compilation is ok for "111" but not ok for "101". (It's an example, the true problem appears with a 16 bit signal std_logic_vector).