Agilent Technologies 86120C, User Manual

Page: 216 / 294

4-88
Programming Commands
SENSe Subsystem
DATA?
Queries the time domain samp les of the inp ut laser line.
Syntax
:SENSe:DATA?
Attribute
Summary Preset State: none
SCPI Comp liance: instrument sp ecific
Query Only
Description Be p rep ared to p rocess a large amount of data when this query is
sent. The amount of data returned depends on the measurement
update state of the instrument which is set using the resolution argu-
ment of an instrument function.
Refer to “Measurement Instructions”
on page 4- 15 .
When NORMAL measurement up date is sp ecified, over 2,200 kilobytes
of data (2
17
values) can be returned to the comp uter. When FAST mea-
surement up date is sp ecified, over 1,100 kilobytes of data (2
16
values)
can be returned.
The floating point values are scaled from 1.000 to 1.999756 (1 + 4095/
4096). Amplitude values are not calibrated.
The input laser line(s) generate an interference pattern on the photo-
detector as a function of the Michelson interferometer optical path
delay. The time domain data is samp led at uniform op tical p ath delay
increments of the reference laser wavelength, or 0.632991 microns.
When
NORMAL measurement update is selected, the first data value is
samp led at –41.48 mm op tical p ath delay, and the last value is sam-
pled at +41.48 mm optical path delay. When
FAST measurement up date
is selected, the first data value is samp led at +20.74 mm op tical p ath
delay, and the last value is samp led at –20.74 mm op tical p ath delay.
The data value that corresp onds to zero op tical p ath delay is ap p roxi-
mately, but not exactly, located in the center of the time domain data.
If your program is aborted or interrupted after sending this query, the
Agilent 86120C continues to p rocess the data but does not p lace it in
the outp ut buffer. Because of the amount of data p rocessed, the
instrument
will not respond to any new commands in its inp ut buffer
for 30 or 40 seconds .