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TLS 216 User Manual
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Choosing an Acquisition Mode
The TLS 216 Logic Scope provides three modes for acquiring signals, digitizing
them, and displaying them as waveforms on screen. To choose from these
modes, you need to understand how each mode acquires and processes the
signals you input to the logic scope.
This article briefly describes each mode: how each acquisition mode operates,
how to check acquisition mode and status, how to choose an acquisition mode,
and how to start and stop acquisitions.
To Understand the Acquisition Modes
To more effectively use the acquisition modes, take the following steps to
become familiar with all three modes the logic scope uses to acquire data:
Sample, Envelope, and Average.
1. Examine Figure 3-5 to get a quick overview of the different modes and lists
the benefits of each. It will help you select the appropriate mode for your
application.
2. Read the following descriptions of how each mode works. Knowing how
each mode works helps you apply them properly to specific applications.
In Sample mode, the logic scope creates a record point by saving the first sample
(of perhaps many) during each acquisition interval. (An acquisition interval is
the time covered by the waveform record divided by the record length.) Sample
mode is the default mode.
Sample mode operates in real time on a single trigger event, provided the logic
scope can acquire enough samples for each trigger event.
Envelope mode allows you to acquire and display a waveform record that shows
the extremes in variation over several acquisitions. You specify the number of
acquisitions over which to accumulate the data. The logic scope saves the highest
and lowest values in two adjacent intervals. Envelope mode gathers peaks over
many trigger events.
After each trigger event, the logic scope acquires data and then compares the
min/max values from the current acquisition with those stored from previous
acquisitions. The final display shows the most extreme values for all the
acquisitions for each point in the waveform record.
Envelope mode only operates on multiple acquisitions.
Sample Mode
Envelope Mode