Ceyear 3986 Series, Руководство по программированию

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2 Remote Control
2.1 Remote control basis
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- Setting command: Change the instrument setting status, e.g. reset the instrument or set the frequency.
- Query command: Query and return the data, e.g. identify the instrument or query the parameter values.
The query command is always ended with a question mark.
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Based on the definition in the standard:
- Common commands: Functions and syntax defined by IEEE488.2 for all types of instruments (if
implemented)
Used to implement: manage standard status registers, resets and self-tests.
- Instrument control command: Instrument characteristic command for realizing instrument function. For
example: set the frequency.
The syntax also follows SCPI specification.
b) Instrument response:
The instrument response (response message and service request) is the query result information sent
by the instrument to the computer. This information includes measurement result and instrument status.
2.1.3 SCPI
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Introduction to SCPI
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Description of SCPIs
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2.1.3.1 Brief introduction to SCPI
SCPI (Standard Commands for Programmable Instruments) is a command set that is established based
on IEEE Standard 488.2 and applicable to all instrument. mainly to achieve the universality of SCPI,
i.e.the same SCPI is generated and issued for the same function.
The SCPI consists of a command header and one or more parameters which are separated by a space.
The command header contains one or more key fields. The command with question mark as postfix is a
query command. Commands are divided into common commands and instrument-specific commands
that are different in syntactic structure. SCPI has the following features:
1) The SCPI is established for the test functions rather than instrument operation description.
2) The SCPI reduces the repetition of the realization process of similar test functions, thus ensuring the
programming compatibility;
3) Remote control message is defined in a layer that is independent of the communication physical
layer hardware.
4) The SCPI is irrelated with the programming methods and languages, and the SCPI test program is
easy to be transplanted;
5) The SCPI is scalable so that it is applicable to measurement control on different scales.
6) Scalabil
ity makes SCPI a “Live” standard.
If you are interested in learning more about SCPI, please refer to:
IEEE Standard 488.1-1987, IEEE Standard Digital Interface for
Programmable Instrumentation. New York, NY, 1998.
IEEE Standard 488.2-1987, IEEE Standard Codes, Formats, Protocols and Comment
Commands for Use with ANSI/IEEE Std488.1-1987. New York, NY, 1998
Standard Commands for Programmable Instruments(SCPI) VERSION 1999.0.
For the collection of remote control commands, classification and description of 3986 noise factor
analyzer, please refer to: