
Chapter 4 Connecting Signals
© National Instruments Corporation 4-19 NI PCI-6110/6111 User Manual
Figure 4-10.  Typical Pretriggered Acquisition
TRIG1 SignalAny PFI pin can receive as an input the TRIG1 signal, which is available 
as an output on the PFI0/TRIG1 pin.
Refer to Figures 4-9 and 4-10 for the relationship of TRIG1 to the 
DAQsequence.
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 starts the DAQ sequence for both posttriggered and pretriggered 
acquisitions. The NI PCI-6110/6111 supports analog triggering on the 
PFI0/TRIG1 pin. Refer to Chapter3, Hardware Overview, for more 
information on analog triggering.
As an output, TRIG1 reflects the action that initiates a DAQ sequence even 
if another PFI is externally triggering the acquisition. The output is an 
active high pulse with a pulse width of 25to 50 ns. This output is set to 
high-impedance at startup.
n/a
01231 0222
TRIG1
TRIG2
STARTSCAN
CONVERT*
Scan Counter