KEPCO KLN 100-7.5, Руководство оператора

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3-30
KLN 750W 121912
3.7 SCPI PROGRAMMING
SCPI (Standard Commands for Programmable Instruments) is a programming language con-
forming to the protocols and standards established by IEEE 488.2 (reference document
ANSI/IEEE Std 488.2, IEEE Standard Codes, Formats, Protocols, and Common Commands
). The KLN
750W Power Supply supports long and short form syntax as defined in this standard. All other
aspects of this standard are specified in appendix B of this manual. The unit ignores all incor-
rectly formatted messages, emitting an audible beep for each incorrect command sequence; the
reason for the beep is placed in the error queue.
Different programming languages (e.g., BASIC, C, PASCAL, etc.) have different ways of repre-
senting data that is to be put on the IEEE 488 bus. It is up to the programmer to determine how
to output the character sequence required for the programming language used. Address infor-
mation (GPIB address) must be included before the command sequence. (See PAR.3.3.17 to
establish the KLN 750W Power Supply GPIB address.)
3.7.1 SCPI MESSAGES
There are two kinds of SCPI messages: program messages from controller to power supply,
and response messages from the power supply to the controller. Program messages consist of
one or more properly formatted commands/queries and instruct the power supply to perform an
action; the controller may send a program message at any time. Response messages consist of
formatted data; the data can contain information regarding operating parameters, power supply
state, status, or error conditions.
3.7.2 COMMON COMMANDS/QUERIES
Common commands and queries are defined by the IEEE 488.2 standard to perform overall
power supply functions (such as identification, status, or synchronization) unrelated to specific
power supply operation (such as setting voltage/current). Common commands and queries are
preceded by an asterisk (*) and are defined and explained in Appendix A.
3.7.3 SCPI SUBSYSTEM COMMAND/QUERY STRUCTURE
Subsystem commands/queries are related to specific power supply functions (such as setting
output voltage, current, etc.) Figure 3-10 is a tree diagram illustrating the structure of SCPI sub-
system commands used in the KLN 750W Power Supply with the root at the left side, and spe-
cific commands forming the branches. The following paragraphs introduce the subsystems;
subsystem commands are defined and explained in Appendix B.
3.7.3.1 CALIBRATE SUBSYSTEM
This subsystem is used to calibrate the unit, however these commands and queries are not
accessible to the user.
3.7.3.2 DISPLAY SUBSYSTEM
This subsystem is used to set and ascertain the brightness on the front panel Voltage and Cur-
rent displays.
3.7.3.3 FETCH SUBSYSTEM
This subsystem is used to measure and return both voltage and current measurements.