B&K Precision 4034 - Manual - Manual (Page 39)

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4.8 Self Test
The *TST common query causes the device to perform a self test. This self test consists of checking the functionality
of the pulse generator.
4.9 Command Syntax
4.9.1 General Command Structure
The device commands are generally defined by the SCPI standard, with the exception of those
instrument functions for which SCPI commands do not as yet exist.
The Common Commands and Queries are defined by IEEE 488.2. The command syntax, i.e. how a
command is structured, is defined by IEEE 488.2.
4.9.2 The Program Message
A Program Message is defined as a string containing one or more Program Message Units, each of
which is an instrument command or query. Program Message Units are separated from each other by
the Program Message Unit Separator. The Program Message is terminated by the Program Message
Terminator.
The Program Message Unit Separator consists of a semicolon (';'), optionally preceded and/or followed
by white-space characters. A white-space character is defined as the ASCII characters in the ranges
00H-09H, and 0BH-20H. This range includes the ASCII control characters and the space, but excludes
the Linefeed character.
The Program Message Terminator consists of optional white-space characters, followed by one of three
options:
- Linefeed (LF) character (ASCII 0A);
- GPIB EOI bus line being set true on the last byte of the message;
- LF being sent with EOI true.
The Program Message Unit can be divided into three sections as follows.
4.9.2.1 Program Message Header
The Program Header represents the operation to be performed, and consists of ASCII character
mnemonics. Two types of Program Headers are used in the pulse generator: Instrument-control headers
and Common Command and Query headers. A Program Header may consist of more than one
mnemonic, in which case the mnemonics are separated from each other by the colon (':'). For
instrument control commands, the mnemonics are specified by the SCPI standard, and indicate the tree
structure of the command set. The first mnemonic indicates the subsystem being controlled. Common
Command and Query Program Headers consist of a single mnemonic prefixed by an asterisk ('*').
The mnemonics consist of upper- or lower-case alpha characters. Mnemonics may be written in either
the long form, in which the entire mnemonic is written out, or the short form, in which only a specified
portion of the mnemonic is written out. Some mnemonics have only one form due to their short length.
Where a command is described, the portion appearing in upper case is the short form. Only the short
form or the long form may be used.
Example: The command to set the period to 1 microsecond may be written in the following ways:
SOURCE:PULSE:PERIOD 1US
SOUR:PULS:PER 1US
SOURCE:PULSE:PERIOD 1US
Some mnemonics in a specified Program Header may be optional. This is indicated in the command
description by the mnemonic being enclosed in square brackets ([...]).