Triggering 4
InfiniiVision 7000B Series Oscilloscopes User’s Guide 151
6 Press the D+ and D– softkeys to select the channel connected to the
USB signal D+ and D– lines. The D+ and D– labels for the source
channels are automatically set.
As you press the D+
or D– softkey (or rotate the Entry knob), the D+ and
D– label for the source channel is automatically set and the channel you
select is shown in the upper-right corner of the display next to “USB”.
If you have connected the oscilloscope’s analog source channels to the
D+ and D- signals: Adjust the trigger level for each connected analog
channel to the middle of the waveform by pressing the D+ or D- softkey,
then turning the Trigger Level knob.
If you have connected the oscilloscope’s digital source channels to the
D+ and D- signals (this applies to MSO model oscilloscopes only): Press
the [Digital] key and select Thresholds to set an appropriate threshold
level for the digital channels.
The value of the trigger level or digital threshold is displayed in the
upper- right corner of the display.
7 Press the Trigger: softkey to select where the USB trigger will occur:
• SOP (Start of Packet) — triggers at the Sync bit at the beginning of
the packet.
• EOP (End of Packet) — triggers at the end of the SE0 portion of the
EOP.
• RC (Reset Complete) — triggers when SE0 is > 10 ms.
• Suspend (Enter Suspend) — triggers when the bus is idle > 3 ms.
• Exit Sus (Exit Suspend) — triggers when exiting an idle state > 10 ms.
This is used to see the suspend/resume transition.
Bus Idle
SOP
SE0 portion of EOP
End of packet trigger
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