Agilent Technologies N3280A Scpi Command Completion, Suffixes and Multipliers, Common Multipliers

4 - Introduction to Programming

Suffixes and Multipliers

	Class	Suffix	Unit	Unit with Multiplier
	Current	A	ampere	MA (milliampere)
	Amplitude	V	volt	MV (millivolt)
	Time	S	second	MS (millisecond)
			Common Multipliers
		1E3	K	kilo
		1E-3	M	milli
		1E-6	U	micro
Response Data Types

Character strings returned by query statements may take either of the following forms, depending on the length of the returned string:

<CRD> Character Response Data. Permits the return of character strings.

<AARD> Arbitrary ASCII Response Data. Permits the return of undelimited 7-bit ASCII. This data type has an implied message terminator.

<SRD> String Response Data. Returns string parameters enclosed in double quotes.

SCPI Command Completion

SCPI commands sent to the dc source are processed either sequentially or in parallel. Sequential commands finish execution before a subsequent command begins. Parallel commands allow other commands to begin executing while the parallel command is still executing. Commands that affect trigger actions are among the parallel commands.

Following is a list of parallel commands. A user should use some form of synchronization before assuming that these commands have completed.

OUTPUT:STATE	INITIATE
VOLT	OUTPUT:PROTECTION:CLEAR
CURR	FUNC:MODE
CURR:LIM	VOLT:ALC:BWIDTH

NOTE: The power supply already provides automatic source settling delay for the special case of VOLT, CURR, or CURR:LIM followed by a measure query, so it is not necessary to use *WAI before a measure if the only pending operations are in this group.

The *WAI, *OPC, and *OPC? common commands provide different ways of indicating when all transmitted commands, including any parallel ones, have completed their operations. The syntax and parameters for these commands are described in chapter 6. Some practical considerations for using these commands are as follows:

*WAI	This prevents the dc source from processing subsequent commands until all pending
	operations are completed.
*OPC?	This places a 1 in the Output Queue when all pending operations have completed.
	Because it requires your program to read the returned value before executing the next
	program statement, *OPC? can be used to cause the controller to wait for commands to
	complete before proceeding with its program.

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