KEPCO KLN 750W Series, Firmware Version 1.60 to 1.6x - Manual (Page 66)

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KLN 750W 032614
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. See Table 3-7
for VISA resource strings corresponding to RS-485, GPIB (G-suffix models only) or LAN (E-suf-
fix models only) interfaces.
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.
TABLE 3-7. VISA RESOURCE STRING CORRESPONDING TO INTERFACE
INTERFACE VISA RESOURCE STRING COMMENT
GPIB GPIB::xx::INSTR The GPIB address replaces xx. Address information not included with
command sequences. See PAR. 3.3.17 to set GPIB address.
RS-485 ASRLy::INSTR The com port number replaces y. RS 485 address must be included in
each command sequence. See PAR. 3.3.18 to set RS-485 address.
LAN TCIP::192.168.0.100::5025::SOCKET 5025 is the default socket. See PAR 3.6.3.1, step 3 to verify or change the
socket port. Address information not included with command sequences.