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Section 3: Functions and features
Model 2657A High Power System SourceMeter® Instrument Reference Manual
3-42
2657A-901-01 Rev. B/December 2012
Figure 45: External instrument triggering
Action overruns on hardware lines
An action overrun occurs when a trigger event is received before the digital I/O or TSP-Link
®
line is
ready to process it. The generation of an action overrun is dependent upon the trigger mode selected
for that line. For more details on the causes of action overruns, see
(on page
3-55). Use the status model to monitor for the occurrence of action overruns (for details, see the
(on page E-1)).
Timers
A timer is a trigger object that performs a delay when triggered. Timers can be used to create delays
and to start measurements and step the source value at timed intervals. When a delay expires the
timer generates a trigger event. The Model 2657A has eight independent timers.
Timer attributes
The attributes that can be configured for each timer are described in the following sections.
Count
Configures the number of events to generate each time the timer is triggered. Each event is
separated by a delay.
To configure the count, use the following attribute:
trigger.timer[
N
].count
Set the count number to 0 (zero) to cause the timer to generate trigger events
indefinitely.
Trigger event:
digio.trigger[2].EVENT_ID
Trigger event:
smua.trigger.SWEEP_COMPLETE_EVENT_ID
Stimulus input:
smua.trigger.source.stimulus
Stimulus input:
digio.trigger[4].stimulus
SMU A
Legend:
= Trigger object
= External input trigger
= External output trigger
= Trigger events
= Stimulus input
Hardware triggers
DIGITAL
I/O
(line 2)
DIGITAL
I/O
(line 4)
Summary of Contents for 2657A
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