By default, the scope starts acquiring data at the same time as the trigger event (the trigger point). Sometimes, to observe the values that led to the trigger, you start acquiring data a given number of samples before the trigger event (pretriggering). Other times, to observe the system settling after the trigger, you delay acquiring data a given number of samples after the trigger event (posttriggering).
NumPrePostSamples scope property
to specify pretriggering and posttriggering. A negative value indicates
pretriggering and a positive value indicates posttriggering. For example,
P is the value of
Scope 1 and
TP is the trigger point, the sample
where the trigger event occurs.
P = 0 —
Scope 1 starts acquiring data immediately at trigger point
< 0 — Scope 1 starts acquiring data
before trigger point
> 0 — Scope 1 starts acquiring data
after trigger point