start on rising edge and stop acquiring signal on on falling edge

[khan_khalil]

i have an automatically generated start/stop trigger which controls analogue data acquisition. the data is simply acquired and saved to file for some post processing later. my trigger input is on the PFI rising edge to start, falling edge to stop. trigger signals are produced externally with some logic circuit. at present i'm using  usb6009 as a executable built from l'view 8.

i'd like to convey to the user some status information, i.e. that the system is preparing to acquire data between the stop-start trigger. and that it is acquiring data between the start-stop trigger.


hope my explanation makes sense?

regards, Khalil

[Ervin_Seferi]

One way is to run trigger in a flat sequence. if the trigger block is done then you can signal the user on the next frame?

[khan_khalil]

I did not understand it, Can you please explain it a bit more.

Regards;

[Izzzzz]

Hello Khan_Khalil

I believe what Ervin_Seferi is referring to is this

Also, this can be achieved by using a state structure such as the example below. 

Regards,

Izzy O.

Applications Engineer

National Instruments 

[khan_khalil]

Thanks a lot for the quick reply.

Actually the conditions that can be set for triggering are a bit different.

In Pre-triggering, you will get pre defined number of samples before the trigger occurs.

In Post triggering. you will get pre defined number of samples after the trigger occurs.

I want to start acquiring on first trigger and stop on the second trigger.

Hope you will have understand why I want to do.

Regards;

[Ervin_Seferi]

Try this. And yes start on rising(digital) edge does not sample prior or after unless you are triggering off a digital pattern. This might apply to analog triggering under analog window.