HBM GEN3i, Руководство пользователя

Страница: 143 / 1160

10 Digital Trigger Modes
10.1 Introduction
Within the GEN3i data acquisition system, every channel is equipped with a
trigger detector , which makes it possible to record just the phenomenon of
interest, instead of having to search the full memory to find it. The trigger
detector gives the system the power to capture elusive, short and unpredictable
events. It determines how easily the event of interest can be extracted.
The word trigger has a dual meaning in recording techniques. In the active
sense, the instrument has triggered, indicating that the instrument has
responded to a certain stimulus. In the passive sense, as in trigger point, it
indicates the point (in time) when the instrument has triggered. In both cases,
trigger refers to a known, pre
-
defined situation.
The trigger can be generated in several ways:
l
by the user, i.e. manually
l
using an externally applied signal, i.e. external trigger
l
when the acquired signal complies with a certain condition: the trigger
condition. Each channel within a recorder can trigger this recorder.
For transient recording, this last option is of great importance. To a large extent,
the trigger facilities determine the application capabilities of the data acquisition
system, i.e. how effectively the data can be captured.
In this chapter, the trigger capabilities of the GEN3i data acquisition system will
be explained in full detail.
Each channel within a recorder can trigger this recorder. This functionality is
realized by combining all channel triggers into a logical OR combination. When
one of the channels (or multiple channels) generates a trigger, the complete
recorder triggers. Each channel's trigger detector can be switched off or set to
one of the modes described in this chapter.
Note This chapter describes all GEN series trigger options. However, not every
acquisition card will support each described option. Check the specifications of
each acquisition card to find out what options are supported for this specific
card.
GEN3i
I3763-3.1 en HBM: public 143