Agilent Technologies InfiniiVision 7000A Series Programmer's Manual page 619

5
Commands by Subsystem
acquired using NORMal. When the data is acquired using the :DIGitize
command (see page 150) or :RUN command (see page 174), 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 626) 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? (see page 188).
Helpful Hints:
The number of points transferred to the computer is controlled using the
:WAVeform:POINts command (see page 629). If :WAVeform:POINts
MAXimum is specified and the instrument is not running (stopped), all of
the points that are displayed are transferred. This can be as many as
4,000,000 in some operating modes or as many as 8,000,000 for a digital
channel on the mixed signal oscilloscope. Fewer points may be specified to
speed data transfers and minimize controller analysis time. The
:WAVeform:POINts may be varied even after data on a channel is acquired.
However, this decimation may result in lost pulses and transitions. The
number of points selected for transfer using :WAVeform:POINts must be an
even divisor of 1,000 or be set to MAXimum. :WAVeform:POINts determines
the increment between time buckets that will be transferred. If POINts =
MAXimum, the data cannot be decimated. For example:
• :WAVeform:POINts 1000 — returns time buckets 0, 1, 2, 3, 4 ,.., 999.
• :WAVeform:POINts 500 — returns time buckets 0, 2, 4, 6, 8 ,.., 998.
• :WAVeform:POINts 250 — returns time buckets 0, 4, 8, 12, 16 ,.., 996.
• :WAVeform:POINts 100 — returns time buckets 0, 10, 20, 30, 40 ,..,
990.
Analog Channel Data
NORMal Data
Normal data consists of the last data point (hit) in each time bucket. This
data is transmitted over the programming interface in a linear fashion
starting with time bucket 0 and going through time bucket n - 1, where n
is the number returned by the :WAVeform:POINts? query (see page 629).
Only the magnitude values of each data point are transmitted. The first
voltage value corresponds to the first time bucket on the left side of the
Agilent InfiniiVision 7000A Series Oscilloscopes Programmer's Guide 619