Optional Parameters

Definite length block:

#<non-zero digit><digit(s)><data byte(s)>

Where the value of <non-zero digit> equals the number of <digit(s)>. The value of <digit(s)> taken as a decimal integer indicates the number of <data byte(s)> in the block.

Command parameters shown within square brackets ([ ]) are optional. The brackets are not part of the syntax and are not sent to the digitizer. If you do not specify a value for an optional parameter, the instrument chooses a default value.

For example, consider the command

CONFigure[<chan >]:ARRay[:VOLTage][:DC] (<size >)

[,<expected value >[,<resolution >]] [,(@<input port >)]

Querying Parameter Settings

If you send the command without specifying the expected value, resolution, or input port parameters, the digitizer sets default values. Similarly, if chan in the command keyword is not specified, the default channel 1 is used.

Unless otherwise noted in the subsystem syntax, parameter settings can be queried by adding a question mark (?) to the command. For example:

TRIG:SOUR HOLD

sets the trigger source to HOLD. The value can be queried by executing:

TRIG:SOUR?

The MINimum or MAXimum value of a parameter is determined by adding the word MIN or MAX to the end of the query. See below.

SENS:SWE:OFFS:POIN? MIN

SENS:SWE:OFFS:POIN? MAX

The minimum and maximum values returned are based on the current settings of other digitizer parameters.

SCPI Command Execution

The following information should be remembered when executing SCPI commands.

Command Coupling Some of the digitizer SCPI commands are functional or value coupled. Functionally coupled commands are those that for one command to have affect, another command must be set to a particular value. A value coupled command changes the settings of other commands.

182 Command Reference

Chapter 4

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HP E1429A manual Scpi Command Execution, Optional Parameters, Querying Parameter Settings, Definite length block