Agilent Technologies 54621A Programmer's Manual page 90

Introduction
The Programmer's Quick Reference provides the commands and queries
with their corresponding arguments and returned formats for the
oscilloscopes. The arguments for each command list the minimum
argument required. The part of the command or query listed in
uppercase letters refers to the short form of that command or query. The
long form is the combination of the uppercase and lowercase letters. Any
optional parameters are listed at the end of each parameter listing.
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