4 program message structure, Table 3-4. scpi command index, 1 keyword – KEPCO MST 488 Programmer User Manual

Page 34: Program message structure -8, Keyword -8, Scpi command index -8, E 3-4)

3-8

MST488-27 013004

3.4.4

PROGRAM MESSAGE STRUCTURE

SCPI program messages consist of one or more message units ending with a terminator. The ter-
minator is not part of the syntax; it is defined by the way your programming language indicates
the end of a line. The message unit is a keyword consisting of a single command or query word
followed by a terminator (e.g., CURR? or TRIG). The message unit may
include a data parameter after the keyword separated by a space; the parameter is usually
numeric (e.g., CURR 5), but may also be a string (e.g., OUTP ON). Figure
3-3 illustrates the message structure, showing how message units are combined. The following
subparagraphs explain each component of the message structure.

NOTE: An alternative to using the message structure for multiple messages defined in the fol-

lowing paragraphs is to send each command as a separate line. In this case each com-
mand must use the full syntax shown in Appendix B.

3.4.4.1

KEYWORD

Keywords are instructions recognized by a decoder within the MST 488-27 controller, referred to
as a “parser.” Each keyword describes a command function; all keywords used by the MST 488-
27 controller are listed in Figure 3-2.

TABLE 3-4. SCPI COMMAND INDEX

COMMAND

PAR.

REFERENCE

COMMAND

PAR.

REFERENCE

COMMAND

PAR.

REFERENCE

*CLS

A.2