The chronometer does show the time since the last event, even if it was of another type. You can double-check it by setting 2 breakpoints inside the LEDBlink loop. If it doesn’t work as expected, please share the repro steps along with the relevant screenshots per our problem reporting guidelines and we will investigate it.
You can also switch the chronometer to show the absolute timestamps (i.e. from the beginning of the session) to minimize confusion.
P.S. If the absolute timestamps don’t make sense, some code inside your project might be resetting the ARM cycle counter that is used by the chronometer. E.g. VisualGDB’s profiler does that to avoid overflows.