Figure 4-12. typical posttriggered acquisition, Figure 4-13. typical pretriggered acquisition, Trig1 signal – National Instruments NI 6120 User Manual
Page 59: Trig1 signal -21
Chapter 4
Connecting Signals
© National Instruments Corporation
4-21
Figure 4-12. Typical Posttriggered Acquisition
Pretriggered data acquisition allows you to view data that is acquired before
the trigger of interest in addition to data acquired after the trigger.
Figure 4-13 shows a typical pretriggered DAQ sequence. The description
for each signal shown in these figures appears later in this chapter.
Figure 4-13. Typical Pretriggered Acquisition
TRIG1 Signal
Any PFI pin can receive as an input the TRIG1 signal, which is available
as an output on the PFI0/TRIG1 pin.
Refer to Figures 4-12 and 4-13 for the relationship of TRIG1 to the DAQ
sequence.
As an input, TRIG1 is configured in the edge-detection mode. You can
select any PFI pin as the source for TRIG1 and configure the polarity
selection for either rising or falling edge. The selected edge of TRIG1 starts
the DAQ sequence for both posttriggered and pretriggered acquisitions.
The NI 6115/6120 supports analog triggering on the PFI0/TRIG1 pin.
1
3
0
4
2
TRIG1
STARTSCAN
CONVERT*
Scan Counter
n/a
0
1
2
3
1
0
2
2
2
TRIG1
TRIG2
STARTSCAN
CONVERT*
Scan Counter