HP E4418B Programming Manual page 432

Example
Reset Condition
On reset, the trigger source is set to IMMediate.
Query
TRIGger:SOURce?
The query returns the current trigger source, either IMM, BUS or HOLD.
Query Example
HP E4418B/E4419B Programming Guide
TRIG:SOUR IMM
TRIG:SOUR?
TRIGger[1|2]:SOURce BUS|IMMediate|HOLD
This command configures
channel A for immediate
triggering.
This command queries
channel A's trigger source.
TRIGger Subsystem
12-13