Agilent Technologies 5000 Series manual Helpful Hints, Analog Channel Data

3Commands by Subsystem

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 130).

Helpful Hints:

The number of points transferred to the computer is controlled using the :WAVeform:POINts command (see page 413). 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. 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 GPIB 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 413). 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 screen and the last value corresponds to the next- to- last time bucket on the right side of the screen. Time buckets without data return 0. The time values for each data point correspond to the position of the data point in the data array. These time values are not transmitted.

AVERage Data

AVERage data consists of the average of the first n hits in a time bucket, where n is the value returned by the :ACQuire:COUNt query (see

page 127). Time buckets that have fewer than n hits return the average of the data they do have. If a time bucket does not have any data in it, it returns 0.

404 Agilent InfiniiVision 5000 Series Oscilloscopes Programmer's Reference