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1 scpi messages, 2 common commands/queries, 3 scpi subsystem command/query structure – KEPCO BHK-MG 40W (Half Rack) Series User Manual

Page 67: 1 abort subsystem, 2 initiate subsystem, 3 list subsystem, 4 measure subsystem, 5 output subsystem, Scpi messages -23, Common commands/queries -23

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BHK-1/2-MG 121313

3-23

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 (see Table 4-4). Refer
also to syntax considerations (PARs 3.7.3 through 3.7.6).

3.7.3

SCPI SUBSYSTEM COMMAND/QUERY STRUCTURE

Subsystem commands/queries are related to specific power supply functions (such as setting
output voltage, current limit, etc.) Figure 3-4 is a tree diagram illustrating the structure of SCPI
subsystem commands used in the BHK-MG 40W Power Supply with the “root” at the left side,
and specific commands forming the branches. The following paragraphs introduce the subsys-
tems; subsystem commands are defined and explained in Appendix B.

3.7.3.1

ABORT SUBSYSTEM

This subsystem allows pending trigger levels to be cancelled.

3.7.3.2

INITIATE SUBSYSTEM

This subsystem enables the trigger system. When a trigger is enabled, the triggering action will
occur upon receipt of a GPIB , *TRG or TRIGger command. If a trigger circuit is not
enabled, all trigger commands are ignored.

3.7.3.3

LIST SUBSYSTEM

The LIST subsystem is represented by 250 memory locations (groups of settings) which are
stored in the volatile memory. Each setting contains values for: Current, Voltage, and Time. The
range for the first two values is the maximum available range for the specific power supply. The
Time setting is between 0.01 and 655.35 seconds.

3.7.3.4

MEASURE SUBSYSTEM

This query subsystem returns the voltage and current measured at the power supply's output
terminals.

3.7.3.5

OUTPUT SUBSYSTEM

This subsystem controls the power supply's voltage and current outputs