DAQ Software Trigger

[v.derti]

I have a cDAQ board (8-slot 9188) that measures strain and voltage. Right now i am using hardware trigger for the measurement, but for a number of reasons i want to sift to software trigger.

I consulted this solution

https://forums.ni.com/t5/Example-Programs/Software-Trigger-for-Analog-Input-Task-Using-LabVIEW-with-...

which seems OK for my requirements, provided it can switch to follow the points below:

1. I have 20 channels that i want to track in continuous DAQ mode.

2. Out of these there should be 2 trigger channels, pretty much as in the linked solution.

3. When the trigger fires up, i want to save the 20 channels in between N1 seconds before the trigger and for N2 seconds ahead (eg 2 seconds pretrigger data and 20 seconds total DAQ time).

Thanks for your time in advance.

[Duffy2007]

Hello v.derti,

only a idea from my side.

1. Start your aquisition
2. Transfer the values from producer loop (aquire) to a consumer loop (post processing) with a queue
3. In the consumer implement a ring buffer so you can get presamples
4. If the analyze start save, read out the ring buffer and start logging for the time you want

Hope this helps a little bit.