1 scpi messages, 2 common commands/queries, 3 scpi subsystem command/query structure – KEPCO BIT 4882F User Manual
Page 31: Scpi messages -3, Common commands/queries -3, Scpi subsystem command/query structure -3

BIT 4882 030507
4-3
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. 2.2.1 to
establish the Interface Card GPIB address.)
4.3.1
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.
4.3.2
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 3.4.3 through 3.4.6).
4.3.3
SCPI SUBSYSTEM COMMAND/QUERY STRUCTURE
Subsystem commands/queries are related to specific power supply functions (such as setting
output voltage, current limit, etc.) Figure 4-1 is a tree diagram illustrating the structure of SCPI
subsystem commands used in the Interface Card with the “root” at the left side, and specific
commands forming the branches. The subsystem commands are defined and explained in
Appendix B (see Table 4-4).
FIGURE 4-1. TREE DIAGRAM OF SCPI COMMANDS USED WITH BIT 4882, BIT 4882-F
AND BIT 4886 INTERFACE CARD
INITiate
[:IMMediate]
:CONTinuous
MEASure
:CURRent?
:VOLTage?
[SOURce:]
VOLTage
[:LEVel]
[:IMMediate]
:TRIGgered
CURRent
[:LEVel]
[:IMMediate]
:TRIGgered
FUNCtion
:MODE
ROOT : (colon)
STATus
:OPERation
:CONDition?
:ENABle
[:EVENt]?
:PRESet
:QUEStionable
:CONDition?
:ENABle
[:EVENt]?
SYSTem
:ERRor?
:LANGuage