Read Commands - Agilent Technologies ESA-E Series User And Programming Manual

If the optional [n] value is not included, or is set to 1, the scalar
measurement results will be returned. If the [n] value is set to a value
other than 1, the selected trace data results will be returned. See each
command for details of what types of scalar results or trace data results
are available.
FETCh may be used to return results other than those specified with
the READ or MEASure commands.

Read Commands

:READ:<measurement>[n]?
• Does not preset the measurement to the factory defaults. (The
MEASure? and CONFigure? commands reset the parameters to the
default values.) READ uses the settings from the last measurement.
• Initiates the measurement which puts new data into the output
buffer. If a measurement other than the current one is specified, the
instrument will switch to that measurement before it initiates the
measurement and returns results.
• Blocks other SCPI communication, waiting until the measurement is
complete before returning the results.
For the EVM measurement, if the optional [n] value is not included,
or is set to 1, the scalar measurement results will be returned. If the
[n] value is set to a value other than 1, the selected trace data results
will be returned. For the Monitor Spectrum measurement, the trace
data will always be returned. See each command for details of what
types of scalar results or trace data results are available.
Measurement settings persist if you initiate a different measurement
and then return to a previous one. Use READ:<measurement>? if you
want to use those persistent settings. If you want to go back to the
default settings, use MEASure:<measurement>?.
Chapter 7
Programming Language Reference
MEASure Group of Commands
115