pre-trigger data

[mfishman]

I work in material testing and am using a striker with a built in strain gauge to break specimens. I am attempting to automate the daq portion so I don't have to stand there waiting to push play. I have figured out how use a trigger and relay so start gathering data, but I can't figure out how to colect the data right before the trigger. I know there is the pre-trigger mod. and the circular buffer but I don't how to set them up. Can anyone help out?

I'm using Dasylab 13.0

[CJ_Butler__DASYLab_Pro]

If you use the Combi Trigger or the Pre-Post Data Trigger, you can configure both pre-trigger and post-trigger number of samples.

The output of the trigger will be a TTL that starts before the trigger point, and continues until the end of the post trigger values. 

The Relay will then correctly release the original signal with the number of pre-trigger samples and post trigger samples. 

There is a size limit... how many samples do you need before and after the trigger point? 

[mfishman]

After I put in the Combi Trigger it made alot of sense. Thanks a lot for your help.