Chapter 3
Connecting the Signals
DAQPad-MIO-16XE-50 User Manual
3-26
ni.com
Figure 3-13.
Typical Pretriggered Acquisition
TRIG1 Signal
Any PFI signal can externally input TRIG1, which is available as an output
on the PFI0/TRIG1 screw terminal.
Refer to Figures 3-12 and 3-13 for the relationship of TRIG1 to the DAQ
sequence.
As an input, the TRIG1 signal 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
the TRIG1 signal starts the DAQ sequence for both posttriggered and
pretriggered acquisitions.
As an output, the TRIG1 signal reflects the action that initiates a DAQ
sequence, even if the acquisition is being externally triggered by another
PFI. The output is an active high pulse with a pulse width of 50 to 100 ns.
This output is set to high-impedance at start up.
Figures 3-14 and 3-15 show the input and output timing requirements for
the TRIG1 signal.
n/a
0
1
2
3
1
0
2
2
2
TRIG1
TRIG2
STARTSCAN
CONVERT*
Scan Counter