Keysight P9241, Scpi Programmer'S Manual

Page: 1000 / 1344

1000 Keysight P9241/42/43A Oscilloscopes SCPI Programmer's Guide
30
:WAVeform Commands
Introduction to
:WAVeform
Commands
The WAVeform subsystem is used to transfer data to a controller from the
oscilloscope waveform memories. The queries in this subsystem will only operate
when the channel selected by :WAVeform:SOURce is on.
Waveform Data and Preamble
The waveform record is actually contained in two portions: the preamble and
waveform data. The waveform record must be read from the oscilloscope by the
controller using two separate commands, :WAVeform:DATA (see page 1007 ) and
:WAVeform:PREamble (see page 1014 ). The waveform data is the actual data
acquired for each point in the specified source. The preamble contains the
information for interpreting the waveform data, which includes the number of
points acquired, the format of acquired data, and the type of acquired data. The
preamble also contains the X and Y increments, origins, and references for the
acquired data, so that word and byte data can be translated to time and voltage
values.
Data Acquisition Types
There are four types of waveform acquisitions that can be selected for analog
channels with the :ACQuire:TYPE command (see page 242 ): NORMal, AVERage,
PEAK, and HRESolution. When the data is acquired using the :DIGitize command
(see page 193 ) or :RUN command (see page 215 ), the data is placed in the
channel buffer of the specified source.
Once you have acquired data with the :DIGitize command, the instrument is
stopped. If the instrument is restarted (via the programming interface or the front
panel), or if any instrument setting is changed, the data acquired with the :DIGitize
command may be overwritten.You should first acquire the data with the :DIGitize
command, then immediately read the data with the :WAVeform:DATA? query (see
page 1007 ) before changing any instrument setup.
A waveform record consists of either all of the acquired points or a subset of the
acquired points. The number of points acquired may be queried using
:ACQuire:POINts[:ANALog]? (see page 232 ).
Helpful Hints:
n/a :WAVeform:YORigin?
(see
page 1033
)
<return_value> ::= y-origin in
the current preamble in NR3
format
n/a :WAVeform:YREFerence?
(see
page 1034
)
<return_value> ::= y-reference
value in the current preamble in
NR1 format
Table 138 :WAVeform Commands Summary (continued)
Command Query Options and Query Returns