Racal Instruments 3162A/B, Руководство пользователя

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3162A/B User Manual
Getting Started 1-8
a trigger signal to output waveform may be programmed from 0 clocks to 8
Million clocks. System delay factor must be added to your calculation of final
delay value.
Burst Mode
The burst mode is an extension of the triggered mode where the Model 3162B
can be armed to output a pre-determined number of waveforms. The source to
trigger the counted burst cycle can be selected from a front panel BNC
connector, VXI backplane trigger lines, or from the built-in trigger generator.
Gated Mode
In gated mode, the Model 3162B circuits are armed to generate output
waveforms as long as a gating signal is true. Unlike the triggered mode, the
gated mode is level sensitive. When the gating signal goes low, the waveform
at the output connector is first completed and the output goes to an idle state.
The idle amplitude level, after the gating signal goes low, is the last point on
the waveform.
Output Type
The Model 3162B can output three types of waveforms: standard (Fixed),
arbitrary (User) and sequenced waveforms. The three types of waveforms are
described in the following paragraphs.
Standard (Fixed)
Waveforms
The Model 3162B generates waveforms from a memory that must be loaded
before the instrument can generate waveforms. There are 1Meg points available
as standard. 2112 points from this memory are allocated for standard
waveforms. Waveforms are loaded into this part of the memory each time that
a standard function is selected.
The Model 3162B can be programmed to output ten different standard
waveforms shapes: sine, triangle, square, pulse, ramp, sinc (sine(x)/x) pulse,
gaussian pulse, exponential pulse, noise, and DC. There are a number of
parameters associated with each waveform which modify the shape of the
waveform to better suit your needs. For example, a different start phase for the
sine waveform can be programmed for each channel to create phase offsets
between the two output channels.
Arbitrary (User)
Waveforms
The arbitrary waveform memory is capable of storing one or more user-defined
waveforms. There are 1,046,464 points that can be allocated to one waveform
which has this length. There is no need to use the entire memory for one
waveform. The memory can be divided into smaller segments, variable in size.
The segments can be loaded with different waveforms and the Model 3162B
can be programmed to output one segment at a time.
Loading data to arbitrary waveform memory can be a time-consuming task,
especially if the complete 1Meg is loaded in one shot. The Model 3162B
utilizes the VXIbus shared memory concept that speeds data transfer from and
to the host computer. In this mode, the memory bank is disconnected from the