Tektronix, Inc. P6240, Руководство пользователя

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TLS 216 User Manual
3–55
Grouping Waveforms
The TLS 216 Logic Scope operates on channels and the waveforms they acquire
only as individual groups. To perform even basic operations on any waveform,
such as displaying, vertically positioning, and vertically scaling it, you must first
know how to include it in a group. This article describes the group concept and
how to define, display, and remove groups.
To Understand Waveform Groups
To more fully understand what a group is, consider its characteristics.
Groups contain one or up to sixteen channels. You must assign a channel to a
group for it to be displayed. See Figure 3-26.
Groups use only contiguous channels. For example, a group can contain
channels 5 through 10, but not channels 5 through 8 plus 10.
Groups cannot share channels. For example if Group 1 contains channel 10, no
other group can include channel 10.
Groups are the objects you display, vertically scale, and vertically position. You
can adjust a single channel like a group only if you make it the only channel in a
group and adjust that group.
Groups can be displayed in any of three display modes: Analog, BusForm, or
Timing Diagram.
Groups allow you to control channels and display the signals they acquire as a
single object or a group, which often best matches the way you want to look at
and measure those signals. For instance, you might wish to measure setup and
hold times of a data bus relative to a clock. Setup and hold times depend on the
behavior of all the data lines on the bus. Therefore, using the logic scope to
display the data lines as a group and to measure the group against the clock
signal is more efficient than comparing each line individually to the clock.
Do not think that because the logic scope focuses on groups, individual channels
cannot be displayed and measured. The ability to operate like a multi-channeled
digitizing storage oscilloscope (DSO) is a key feature of this product.
To use the logic scope as, for instance, a four channel DSO, you define Group 1
through Group 4 to contain one channel each (for instance Channel 1 through
Channel 4, respectively). Because the logic scope treats waveform groups much
like a DSO treats channels (displays them, vertically positions them, and so on)
Focusing on Groups
Focusing on Channels