Keithley 2651A Reference Manual page 149

Section 3: Functions and features
Hardware trigger mode summary
Trigger mode
Bypass
Either Edge
Falling Edge
Rising Edge
RisingA
RisingM
Synchronous
SynchronousA
SynchronousM
Pulsewidth
Specifies the pulse width of the output trigger signal when the hardware line is asserted.
Trigger configuration on hardware lines
The Model 2651A can be configured to send digital signals to trigger external instruments. Linking
these output triggers to the completion of certain source-measure actions enables hardware
handshaking. The programming example below illustrates this:
-- Configure the Model 2651A to detect a rising
-- edge on digital I/O line 2.
digio.trigger[2].mode = digio.TRIG_RISINGA
digio.trigger[2].clear()
-- Configure SMU A to start its source action when a
-- trigger event occurs on digital I/O line 2.
smua.trigger.source.stimulus = digio.trigger[2].EVENT_ID
-- Configure digital I/O line 4 to output a 1 ms
-- rising-edge trigger pulse at the completion of
-- SMU sweep.
digio.trigger[4].mode = digio.TRIG_RISINGM
digio.trigger[4].pulsewidth = 0.001
digio.trigger[4].stimulus = smua.trigger.SWEEP_COMPLETE_EVENT_ID
This example's triggering setup is shown in the following figure.
3-42
Model 2651A High Power System SourceMeter® Instrument Reference Manual
Output
Unasserted Asserted
N/A N/A
High Low
High Low
The programmed state of the line determines if the
behavior is similar to RisingA or RisingM:
• High similar to RisingA
• Low similar to RisingM
High Low
Low High
High latching Low
High latching High
High Low
Input
Detects
N/A
Either
Falling
Rising
None
Falling
Falling
Rising
2651A-901-01 Rev. A / March 2011