Multifunction DAQ

cancel
Showing results for 
Search instead for 
Did you mean: 

Triggered Analog Input

I want to trigger an analog input with a pulse generate
by gating counter 0 with the Analog Output UPDATE* signal.

any suggestion?

Thanks,
Erin
0 Kudos
Message 1 of 2
(2,075 Views)
Response-For what it is worth this isn't a very straight forward thing to
achieve with LabVIEW VIs. I have been trying to do the same thing for a
month now with no luck. If it is any consolation, NI tech support hasn't
provided any working solution to this either. If I get it figured out in
a few days I'll try to remember to write back.

Try using the analog scan clock to trigger the analog read instead of the
traditional "triggering" schemes in the LabVIEW documentation. Their terminology
is misleading. Per LabVIEW the term "trigger" relates to the oscilloscope
concept where you specify voltage level and edge-transition to recognize
a waveform in order to high-speed sample the incoming waveform.

In the embedded system the term "trigger" refers a specifi
c point in time
(defined as an "event") usually represented by a signal transition (rising
or falling edge) at which you want something done such as read an analog
input or save a counter value. In microcontrollers this is generally handled
with a specialized hardware port called an input capture which is designed
to automatically recognized signal transitions and simultaneously fire off
an interrupt (read as "trigger") that can be used to start your unique action.
LabVIEW documentation doesn't seem to have a clue about this concept. Perhaps
you know all this already. Hope it helped in some manner anyway.

Frank


"Erin Ryan" wrote:
>>I want to trigger an analog input with a pulse generate>by gating counter
0 with the Analog Output UPDATE* signal.>>any suggestion?>>Thanks,>Erin
Message 2 of 2
(2,075 Views)