FrontLine BPA LOW ENERGY, Hardware User Manual

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Graphical Packet Depiction - each packet within the visible range is graphically depicted. See the Packet
Depiction section.
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Swap Button - The Swap button switches the position of the Timeline and the Throughput
graph.
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Show Running Average - -Selecting this check box shows a running average in the Throughput Over Time
graph as an orange line
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4.3.2.11 low energy Packet Discontinuities
The following figure depicts a discontinuity between two packets.
Figure 4.42 - Bluetooth® low energy Packet Discontinuity
To keep the timeline and the throughput graph manageable, big jumps in the timestamp are not represented
linearly. Instead, they are shown as discontinuities. A discontinuity exists between a pair of packets when the
timestamp delta (the timestamp of the second packet minus the timestamp of the first packet) is (1) more
than 4.01 seconds or (2) is negative. The reason that the discontinuity trigger is set at 4.01 seconds is because
the maximum connection interval time is 4 seconds.
A discontinuity is indicated by a cross-hatched pattern drawn between two packets and a corresponding
vertical dashed line in the throughput graph. When the timestamp delta is greater than 4.01 seconds, the
discontinuity is a cosmetic convenience that avoids excessive empty space. When the timestamp delta is
negative, the discontinuity is necessary so that the packets can be drawn in the order that they occur.
4.3.2.12 low energy Timeline Navigating and Selecting Data
Buttons, menu items, and keystrokes can be used to go to the next or previous packet, next or previous
invalid interframe spacing (IFS), next or previous error packet, and the first or last packet.
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If there is no selected packet in the timeline, First Packet , Next Packet , and Last Packet
are enabled, but Previous Packet is not.
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A single packet is selected either by clicking on it, navigating to it, or selecting it in the Frame Display .
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Single Segment Navigation:
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Selecting
Previous Packet
will select the next packet in time (moving back in time to the left)
regardless of which row it is on. If the previous packet is not in the display or if a portion of the
packet is visible, the display will scroll to the next packet and it will appear selected on the left of
the display. The timestamp will change with the scrolling of the display.
TELEDYNE LECROY Chapter 4 Capturing and Analyzing Data
86 Frontline BPA low energy Hardware & Software User Manual