Keithley 2651A Reference Manual page 712

Appendix B: Calibration
smua.trigger.measure.action = smua.ASYNC
smua.trigger.measure.stimulus = MeasStartTimer.EVENT_ID
smua.measure.delay = 0
smua.measure.count = 500
smua.measure.interval = 0.000001
-- Use dedicated buffers to receive measurements
smua.nvbuffer1.clear()
smua.nvbuffer2.clear()
-- Use nvbuffer1 for current and nvbuffer2 for volts
smua.trigger.measure.iv(smua.nvbuffer1, smua.nvbuffer2)
-- Generate an external trigger signal on digital I/O connector
-- pin 8 (10 uS falling edge pulse in this example) synchronized
-- to the start of the Fast ADC measurement for use by
-- an external measurement instrument.
digio.trigger[8].mode = digio.TRIG_FALLING
digio.trigger[8].pulsewidth = 10e-6
digio.trigger[8].stimulus = MeasStartTimer.EVENT_ID
-- Set up trigger model state machine for one pulse
-- when smua.trigger.arm.set() command is sent.
smua.trigger.arm.stimulus = trigger.EVENT_ID
smua.trigger.arm.count = 1
smua.trigger.count = 1
-- Enable output (initially at idle level)
smua.source.output = smua.OUTPUT_ON
-- Enter trigger model state machine
smua.trigger.initiate()
-- Start pulse
smua.trigger.arm.set()
waitcomplete()
-- Pulse is done - output can be turned off
smua.source.output = smua.OUTPUT_OFF
-- Retrieve all 500 individual measurements as comma-separated list
-- (parameters can be adjusted to retrieve a subset).
format.data = format.ASCII
printbuffer(1, 500, smua.nvbuffer1) -- current measurements.
printbuffer(1, 500, smua.nvbuffer2) -- voltage measurements.
-- Use getstats functions to retrieve aggregate information
istats = smua.buffer.getstats(smua.nvbuffer1)
vstats = smua.buffer.getstats(smua.nvbuffer2)
print(istats.mean) -- average of current measure
print(vstats.mean) -- average of voltage measure
B-12
Model 2651A High Power System SourceMeter® Instrument Reference Manual
2651A-901-01 Rev. A / March 2011