Tektronix MTX100A, Руководство пользователя

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MTX100A MPEG Recorder & Player User Manual
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Syntax
This section contains information on the Standard Commands for Programmable
Instruments (SCPI) and IEEE 488.2 Common Commands you can use to program
your MTX100A. The information is organized in the following subsections:
SCPI Commands and Queries
SCPI is a standard created by a consortium that provides guidelines for remote
programming of instruments. These guidelines provide a consistent programming
environment for instrument control and data transfer. This environment uses
defined programming messages, instrument responses, and data format across all
SCPI instruments, regardless of manufacturer. The MTX100A uses a command
language based on the SCPI standard.
The SCPI language is based on a hierarchical or tree structure (see Figure 3-30) that
represents a subsystem. The top level of the tree is the root node; it is followed by
one or more lower-level nodes.
Figure 3-30: Example of SCPI subsystem hierarchy tree
You can create commands and queries from these subsystem hierarchy trees.
Commands specify actions for the instrument to perform. Queries return
measurement data and information about parameter settings.
Creating Commands
SCPI commands are created by stringing together the nodes of a subsystem
hierarchy and separating each node by a colon.
In Figure 3-30, RECord is the root node and TARGet, TYPE, SIZE, and TIME are
lower-level nodes. To create a SCPI command, start with the root node RECord and
move down the tree structure adding nodes until you reach the end of a branch.
Most commands and some queries have parameters; you must include a value for
these parameters. If you specify a parameter value that is out of range, the
parameter will be set to a default value.
RECord
TARGet
TYPE SIZE TIME
Root node
Lower-level
nodes