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SCPI Commands HMF series
Remote Control
8
Basics
SCPI Programmers Manual
GPIB Interface Messages
Interface messages are transmitted to the instrument on the data lines with the attention line
(ATN) being active (LOW). They are used for communication between the controller and the
instrument and can only be sent by a PC which has the function of a GPIB bus controller. GPIB
interface messages can be further subdivided into:
•
Universal commands:
act on all instruments connected to the GPIB bus without previous
addressing; universal commands are encoded in the range 10 through 1F hex. They affect all
instruments connected to the bus and do not require addressing.
•
Addressed commands:
only act on instruments previously addressed as listeners;
addressed commands are encoded in the range 00 through 0F hex. They only affect instru-
ments addressed as listeners.
1.4.2 SCPI Command Structure
SCPI commands consist of a so-called header and, in most cases, one or more parameters. The
header and the parameters are separated by a „white space“. The headers may consist of several
mnemonics (keywords). Queries are formed by appending a question mark directly to the hea-
der. The commands can be either device-specific or device-independent (common commands).
Common and device-specific commands differ in their syntax.
Syntax for Common Commands
Common (= device-independent) commands consist of a header preceded by an asterisk (*) and
possibly one or more parameters.
Examples:
*RST
Reset
Resets the instrument.
*ESE
Event Status Enable
Sets the bits of the event status enable registers.
*ESR?
Event Status Query
Queries the content of the event status register.
*IDN?
Identification Query
Queries the instrument identification string.
Table 1.4: Examples of Common Commands
Long and short form
The mnemonics feature a long form and a short form. The short form is marked by upper case
letters, the long form corresponds to the complete word. Either the short form or the long form
can be entered; other abbreviations are not permitted.
Example:
VOLTage:OFFSet? is equivalent to VOLT:OFF?