KEPCO ABC-DM SERIES - Manual (Page 50)

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ABC 040104
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 A-1). 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 3-3 is a tree diagram illustrating the structure of SCPI
subsystem commands used in the ABC 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 ABORT SUBSYSTEM
This subsystem allows pending trigger levels to be cancelled.
3.7.3.2 DISPLAY SUBSYSTEM
This subsystem controls the second line of the LCD. The first line will always display the LOCal
or REMote operation status and the constant Voltage (CV) or constant Current functioning
mode (CC).
3.7.3.3 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.
3.7.3.4 LIST SUBSYSTEM
The LIST subsystem is represented by the 40 memory locations (groups of settings) which are
stored in the nonvolatile memory. Each setting contains values for: Current, Voltage, Overcur-
rent, Overvoltage, Next memory location, and Time. The range for the first four values is the
maximum available range for the specific power supply. The Next memory location is the
address of the next group of settings and is between 1 and 40. A value of 0 means end of chain.
The Time setting is between 0.01 and 300 seconds. In order to access one of the 40 memory
locations an index value must be provided. The 40 memory locations can be very useful in
remote mode using the *RCL command (see Appendix A, PAR. A.10.)
3.7.3.5 MEASURE SUBSYSTEM
This query subsystem returns the voltage and current measured at the power supply's output
terminals.