Agilent Technologies DSO-X 4022A, User Manual

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472 Agilent InfiniiVision 4000 X-Series Oscilloscopes User's Guide
29
USB 2.0 Triggering and Serial Decode
6
For both the D+ and D- signals (for low or full speed, similar steps for
the single Source for high speed):
a
Connect an oscilloscope channel to the signal in the device under
test.
b Press the D+ Source or D- Source softkey; then, turn the Entry knob to
select the channel for the signal.
c
Press the corresponding
Threshold
softkey; then, turn the Entry knob
to select the signal threshold voltage level.
The threshold voltage level is used in decoding, and it will become
the trigger level when the trigger type is set to the selected serial
decode slot.
7 Press Auto Setup to automatically set these options for decoding and
triggering on USB signals:
• Low- speed:
• D+/- Source thresholds: 1.4 V
• D+/- Source vertical scale: 1.0 V/div
• D+/- Source vertical offset: 0.0 V
• Horizontal scale: 5 µs/div
• Full- speed:
• D+/- Source thresholds: 1.4 V
• D+/- Source vertical scale: 1.0 V/div
• D+/- Source vertical offset: 0.0 V
• Horizontal scale: 500 ns/div
• High- speed:
• D+/- Source thresholds: 0.0 V
• D+/- Source vertical scale: 200 mV/div
• D+/- Source vertical offset: 0.0 V
• Horizontal scale: 20 ns/div
• Serial Decode: On
• Trigger Mode: currently active serial bus