triggered data aquisition

[shanky1023]

Hello

i am trying to do a triggered data-acquisition using a trigger function as in my VI.. the trigger keeps jumping from T and F so i set the Reset as F so that once True the state remains the same and my data acquisition starts once

a. I Press the SAVE DATA button

            AND

b. There is a True- Trigger from the rotor.

But this creates only the file and doesn't continuously record data once the trigger has been set. i turned the Highlight execution and i notice that the Trigger O/P keeps changing in spite of me setting the RESET to False.

Could you please help me in this..

Hello
i am trying to do a triggered data-acquisition using a trigger function as in my VI.. the trigger keeps jumping from T and F so i set the Reset as F so that once True the state remains the same and my data acquisition starts once

a. I Press the SAVE DATA button            

AND

b. There is a True- Trigger from the rotor.

But this creates only the file and doesn't continuously record data once the trigger has been set. i turned the Highlight execution and i notice that the Trigger O/P keeps changing in spite of me setting the RESET to False.
Could you please help me in this..

[Dennis_Knutson]

You should read the help for the reset control. It does not set the output to True and keep it there once a trigger is detected. You might want to think about a shift register.

And get rid of that local variable.

[shanky1023]

hi...

yes i realised it just now. but can you help me in understanding as to how a Shift register wud work in this case ??? 

also by removing the local variable do u mean directly wiring the DAQ o/p to the Trigger detection VI ?? how wud that make a difference...

Shankar

[Dennis_Knutson · Accepted solution]

Below is a basic method to latch your trigger. This has been discussed numerous times so I wll leave it up to you to find a method to reset the trigger.

There has been a long discussion lately about the proper and improper use of locals. Yours is really, reall bad style but I have no intention of repeating everything again. Just wire the output of the DAQ Assistant directly to your Convert From Dynamic Data.

[shanky1023]

thanks a lot..

I shall try this tomorrow and also read up more on the  latching triggers and get back.

Shankar

[shanky1023]

Thanks David..

it seems to be working better now.. i am trying to read more on this and make the VI better...