Operating instructions

Language Dictionary
74
TRlG:SOURce Channel-Independent Trigger Command/Query
Description
TRIGger:SOURce selects the electronic load trigger source as follows:
BUS Accepts a GPIB <GET> signal or *TRG command as the trigger source. This
mode guarantees that all previous commands will be completed before the trigger is
executed.
EXTernal Selects the electronic load’s external Trigger jack as the trigger source.
The EXTernal trigger is processed asynchronously with respect to other commands. The
user must ensure that the trigger occurs at a valid time with respect to commands that are
already being processed or are pending.
Note
When TRIG:SOUR BUS is specified for a single electronic load there is brief period (100
µ
s) during which the electronic load can also respond to an external trigger. This situation
does not occur with multiple electronic loads.
HOLD Only the TRIGger:IMMediate command causes a trigger in this mode. All
others, including *TRG, are ignored.
1
LINE This generates triggers in synchronization with the a-c line frequency.
1
TIMer Selects the multiple electronic load’s internal trigger oscillator as the trigger
source. The oscillator begins running as soon as this command is executed. The oscillator
period is selected with the TRIG:TIM command. TRIG:SOUR TIM can be used with
TRAN:MODE PULS to generate synchronous, continuous transient waveforms on
multiple channels.
1
These modes exist only in the multiple electronic load. Programming them in a single
electronic load will generate an error.
Command Syntax
TRIGger:SOURce
Parameters
1
Value Range Units *RST Default
BUS, EXTernal, HOLD
LINE, TIMer
None HOLD
1
The long or short form may be used.
Examples
TRIG Send immediate bus trigger.
TRIG:IMM
TRIG:SOUR HOLD;IMM Disable all sources and send immediate bus trigger.
Query Syntax
TRIG:SOUR?
Returned Parameters
BUS EXT HOLD LINE TIM
Related Commands
&410 <GET> *TRG