Agilent Technologies 6834B, 6814B, 6843A Triggering Output Changes, SCPI Triggering Nomenclature

4 - Programming Examples

Step 4	Determine the number of times the list is repeated before it completes. For example, to
	repeat a list 10 times use:
	LIST:COUNt 10
	Entering INFinity makes the list repeat indefinitely. At *RST, the count is set to 1.
Step 5	Determines how the list sequencing responds to triggers. For a closely controlled
	sequence of output levels, you can use a dwell-paced list. To cause the list to be paced by
	dwell time use:
	LIST:STEP AUTO
	As each dwell time elapses, the next point is immediately output. This is the *RST setting.
	If you need the output to closely follow asynchronous events, then a trigger-paced list is
	more appropriate. In a trigger-paced list, the list advances one point for each trigger
	received. To enable trigger-paced lists use:
	LIST:STEP ONCE
	The dwell time associated with each point determines the minimum time that the output
	remains at that point. If a trigger is received before the previous dwell time completes, the
	trigger is ignored. Therefore, to ensure that no triggers are lost, program the dwell time to
	zero.
Step 6	Use the transient trigger system to trigger the list. This is described in detail under
	"Triggering Output Changes".

Triggering Output Changes

The ac source has two independent trigger systems. One is used for generating output changes, and the other is used for triggering measurements. This section describes the output trigger system. The measurement trigger system is described under "Triggering Measurements".

The basic components of both systems are the same, but the transient trigger system has additional delay and phase synchronization features that the measurement trigger system does not have. The following transient trigger sources can be selected:

IMMediate generates a trigger when the trigger system is initiated.

BUSselects GPIB bus triggers.

EXTernal selects the external Trigger In BNC connector.

SCPI Triggering Nomenclature

In SCPI terms, trigger systems are called sequences. When more than one trigger system exists, they are differentiated by naming them SEQuence1, SEQuence2, ... etc. In the ac source, SEQuence1 is the transient trigger system, SEQuence2 is the phase synchronization trigger system, and SEQuence3 is the measurement trigger system.

The ac source uses aliases with more descriptive names for these sequences. These aliases can be used instead of the sequence forms.

Sequence Form	Alias
SEQuence1	TRANsient
SEQuence2	SYNChronize
SEQuence3	ACQuire

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