IEEE-488 Reference
3-22
<n> Numeric value: A numeric value parameter can consist of an NRf number or
one of the following name parameters; DEFault, MINimum or MAXimum.
When the DEFault parameter is used, the instrument is programmed to the
*RST default value. When the MINimum parameter is used, the instrument
is programmed to the lowest allowable value. When the MAXimum param-
eter is used, the instrument is programmed to the largest allowable value. Ex-
amples:
:TRIGger:TIMer 0.1 Sets timer to 100msec.
:TRIGger:TIMer DEFault Sets timer to 0.1sec.
:TRIGger:TIMer MINimum Sets timer to 1msec.
:TRIGger:TIMer MAXimum Sets timer to 999999.999sec.
<list> List — Specify one or more switching channels. Examples:
:ROUTe:SCAN (@1:10) Specify scan list (1 through 10).
:ROUTe:SCAN (@ 2,4,6) Specify scan list (2, 4 and 6).
Angle brackets < >: Angle brackets (<>) are used to denote parameter type. Do not include
the brackets in the program message. For example:
:SOURce:TTL2 <b>
The <b> indicates that a Boolean type parameter is required. Thus, to set digital input line
#2 true, you must send the command with the ON or 1 parameter as follows:
:SOURce:TTL2 ON or :SOURce:TTL2 1
2. Query commands: This type of command requests (queries) the currently programmed sta-
tus. It is identified by the question mark (?) at the end of the fundamental form of the com-
mand. Most commands have a query form. Example:
:TRIGger:TIMer? Queries the timer interval.
Most commands that require a numeric parameter (<n>) can also use the DEFault, MINi-
mum, and MAXimum parameters for the query form. These query forms are used to deter-
mine the *RST default value, and the upper and lower limits for the fundamental command.
Examples:
:TRIGger:TIMer? DEFault Queries the *RST default value.
:TRIGger:TIMer? MINimum Queries the lowest allowable value.
:TRIGger:TIMer? MAXimum Queries the largest allowable value.
3. Case sensitivity: Common commands and SCPI commands are not case sensitive. You can
use upper or lower case, and any case combination. Examples:
*RST = *rst
:SCAN? = :scan?
:SYSTem:PRESet = :system:preset
4. Long-form and short-form versions: A SCPI command word can be sent in its long-form
or short-form version. The command subsystem tables in this section provide the com-
mands in the long-form version. However, the short-form version is indicated by upper case
characters. Examples: