Agilent Technologies Infiniium 8000A Programmer's Reference Manual page 763

Set the Mode Before Executing Commands
Before you can execute the :TRIGger:ADVanced:DELay commands, set
the mode by entering:
:TRIGger:MODE ADVanced and
:TRIGger:ADVanced:MODE DELay
The ADVanced DELay commands define the conditions for the Delay
Trigger Mode. The Delay By Time Mode lets you view pulses in your
waveform that occur a specified time after a specified waveform edge.
After entering the commands above, to select Delay By Time Mode,
enter:
:TRIGger:ADVanced:DELay:MODE TDLY
Then you can use the Time Delay (TDLY) commands and queries for
ARM, DELay, and TRIGger on the following pages.
To query the oscilloscope for the advanced trigger mode or the advanced
trigger delay mode, enter:
:TRIGger:ADVanced:MODE? or
:TRIGger:ADVanced:DELay:MODE?
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