VXI VT1422A - Manual (Page 258)

256 VT1422A Command Reference Chapter 7
ARM
ARM
The ARM subsystem is only useful when the TRIGer:SOURce is set to TIMer.
With the VT1422A, when the TRIG:SOURCE is set to TIMer, an ARM event must
occur to start the timer. This can be something as simple as executing the
ARM[:IMMediate] command or it could be another event selected by
ARM:SOURCE.
Note
The ARM subsystem may only be used then the TRIGger:SOURce is TIMer. If the
TRIGger:SOURce is not TIMer and ARM:SOURce is set
to anything other than IMMediate, an Error -221,"Settings conflict" will
be generated.
The ARM command subsystem provides:
•
An immediate software ARM (ARM:IMM).
•
Selection of the ARM source (ARM:SOUR BUS | EXT | HOLD | IMM | SCP |
TTLTRG<n>) when TRIG:SOUR is TIMer.
Figure 7-2 shows the overall logical model of the Trigger System.
Figure 7-2. Logical Trigger Model
BUS
EXTernal
HOLD
IMMediate
TTLTrg<n>
SCP Trg
ARM
/TRI
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ARM:SOURce <source>
TRIGger:TIMer <interval>
Trigger
Timer
TIMer
Trigger
Enable
TRIGger:SOURce <source>
Internal
Trigger Signal
Trigger
Counter
TRIGger:COUNt <count>