Chapter 3
Analog Output
©
National Instruments Corporation
3-7
Analog Output Series User Manual
AO Start Trigger Signal
You can use the AO Start Trigger (ao/StartTrigger) signal to initiate a
waveform generation. If you do not use triggers, you begin a generation
with a software command.
Using a Digital Source
To use ao/StartTrigger, 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 signal on your DAQ device. Refer to
Device Routing in MAX
in the
NI-DAQmx Help
or the
LabVIEW Help
in
version 8.0 for more information.
Figure 3-4 shows the timing requirements of the ao/StartTrigger digital
source.
Figure 3-4.
ao/StartTrigger Timing Requirements
Outputting the AO Start Trigger Signal
You can configure the PFI 6/AO START TRIG pin to output the
ao/StartTrigger signal. The output pin reflects the ao/StartTrigger signal
regardless of what signal you specify as its source.
The output is an active high pulse. Figure 3-5 shows the timing behavior of
the PFI 6/AO START TRIG pin when the pin is an output.
Ri
s
ing-Edge
Pol
a
rity
F
a
lling-Edge
Pol
a
rity
t
w
t
w
= 10 n
s
minim
u
m