Agilent Technologies 4000 X-Series User Manual page 472

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USB 2.0 Triggering and Serial Decode
6 For both the D+ and D- signals (for low or full speed, similar steps for
7 Press Auto Setup to automatically set these options for decoding and
472
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.
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
Agilent InfiniiVision 4000 X-Series Oscilloscopes User's Guide