National Instruments Data Acquisition Device E Series - Manual (Page 66)

Chapter 2 Analog Input
© National Instruments Corporation 2-33 E Series User Manual
Using a Digital Source
To use ai/StartTrigger with a digital source, specify a source and an edge.
The source can be an external signal connected to any PFI or RTSI <0..6>
pin. The source can also be one of several internal signals on your DAQ
device. Refer to Device Routing in MAX in the NI-DAQmx Help or the
LabVIEW 8.x Help for more information.
Also, specify whether the measurement acquisition begins on the rising
edge or falling edge of the ai/StartTrigger signal.
Figure 2-19 shows the timing requirements of the ai/StartTrigger source.
Figure 2-19. ai/StartTrigger Timing Requirements
Using an Analog Source
When you use an analog trigger source, the acquisition begins on the first
rising edge of the Analog Comparison Event signal. Refer to Chapter 10,
Triggering , for more information on analog triggering.
Outputting the AI Start Trigger Signal
You can configure the PFI 0/AI START TRIG pin to output the
ai/StartTrigger signal. The output pin reflects the ai/StartTrigger signal
regardless of what signal you specify as its source.
Rising-Edge
Polarity
Falling-Edge
Polarity
t
w
t
w
= 10 ns minimum