Snap-On Vantage Legend, User Manual

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Scope / Multimeter Capturing Data
33
3.10 Capturing Data
The primary purpose and advantage of the Lab Scope and Graphing Multimeter, is
their ability to capture, store and playback data (test signals). Having this ability can
be invaluable when diagnosing intermittent issues, by providing you the ability to
navigate through the data in detail to find events of interest, such as glitches and
signal losses. The following sections describe the basics of the data buffer and the
two basic modes of operation, Capture Mode and Review Mode.
3.10.1 About the Data Buffer
To gain a better understanding of the capabilities of the scope and the basics of
capturing and reviewing data, understanding what the data buffer is and how it
works is important.
The Lab Scope and Graphing Multimeter have the capability to capture, store and
playback data (test signals) utilizing internal buffer storage memory. When a test
function is selected (e.g. Lab Scope > DC Volts), the data is automatically stored in
buffer memory, until the Pause icon is selected.
The amount of data you can capture is limited to a predetermined “total buffer
memory” size. When the buffer memory reaches its full capacity, the data buffer will
continue to store new data, however earlier stored data will be removed to allow
room for the new data being stored. The most recent data is always available for
review when the scope is paused, and can be reviewed using the toolbar controls
As a visual aid, a graphic Data Buffer Slider (
Figure 3-33
( 1 )) is located at the top of
screen and indicates the position of the current displayed frame of data in relation
to the entire buffer memory capacity.
Note:
In Review Mode, the slider can be used
to quickly move through paused data.
In addition, a Data Buffer Position Counter (
Figure 3-33
( 2 )) displays the numerical
position of the Data Buffer Slider within buffer memory.
1— Data Buffer Slider
2— Data Buffer Position Counter (XXX (Total memory “frames” available):
XXX (Whole frame number): XX (Fractional frame number)
Figure 3-33
3.10.2 Capturing Data (Capture Mode)
For control icon descriptions, see
Scope Multimeter Control Icons on page 15
.
Whenever you open Lab Scope or the Graphing Multimeter, the device is in
Capture Mode. In Capture Mode, data is continuously being captured and stored in
buffer memory at the same time it is being displayed onscreen.
NOTE
Data is continuously stored in buffer memory with or without an active input
test signal or trigger.
To help you understand how to work with captured data, an important
concept to remember is that data is captured over a period of time. Therefore
there is a direct relationship between the length of time the data is captured
in, and the resultant level of detail you will have when reviewing it.
1 2