My start trigger is starting immediately - what is wrong?

[flycast]

Newbie, just learning. I have done the NI online training on triggers but is seems to only be a sparse, brief introduction.

I have a NI 9205 in a cDAQ-9185 chassis.

I have three channels wired - 0, 1 and 2.

Channel zero has a 5v battery with a switch.

Channel one has a distance laser range finder with 0-10V output.

Channel two has a 5V battery with a switch.

I am trying to learn how to trigger data collection when channel 2 goes from 0v to 5 volts. I also want collection to stop when the channel goes from 5V to 0V but I am only trying to trigger a start at this point (walk before I run).

I am expecting my chart to not update until I get a transition from 0V to 5V in channel 2. Instead I am getting data immediately when I start the VI.

What am I doing wrong?

My VI image:

[Kevin_Price · Accepted solution]

It's pretty subtle, but grab that Trigger property node and expand it upwards to create another field above (and therefore *before*) the ones you have.  Select the property "Trigger Type" and wire in the constant for "Analog Edge".  Otherwise, the task must assume the default Trigger Type of "None".

This all assumes that your hardware supports analog edge triggering.  If not, digital edge triggering ought to work, it's supported pretty universally, and you've got the right voltage transition range for it (0-5 V).

-Kevin P

[flycast]

Thanks Kevin!

That was it!