[SignalTap] Storage Qualifier

If I understand what you are asking, you want to know if you can get the time of a transition relative to other transitions. I've had similar problems and I don't think SignalTap has a built-in way to do this.

I have not done this in a while, but as I remember, you can add your own counter clocked by the same clock as SignalTap. Add it to the SignalTap list, but make sure to exclude it from the signals that trigger a transition. Otherwise it itself will change every clock cycle making Transitional useless. The counter serves as an absolute time reference.

This of course requires space to store the counter, which reduces the usefulness of Transitional, so make the counter as small as possible.