I don't get the PreTrigg function to work. Attachment include DAC-scheme, datafile and Word-document with further description.
Summary: In my saved data I'm not able to see any "PreTrigger"-data !!? (On the contrary there is a delay of 0.3 seconds / 30 cycles until the "SaveFast" sequence occur !! NI Support: Refer to SRN 165992 )
Indeed the speed is not the problem. Only in a special situation - such you described - it is not possible to collect pre-trigger values, because the current clock step reacts to the stop-trigger and the next clock step reacts to the start-trigger (in the next line). So there is no time to collect any pre-trigger values.
I hope this explains this special behaviour a little bit.
yes, now I think I know how it work (unfortunately!). I't seems the trigger-sequence won't help me in this application. ( I tried a couple of setups and found out that a stop-trigger is required, ... if you want to switch to the next sequence !)
Background / Application ------------------------- The intention is to record data at a slow rate (say 10Hz) while slowly applying load to the test-object. At some point the contol-system (PLC, not DIAdem!) detects a possible breakdown of the test-object, the control-system then signals DIAdem to "record at fast rate (100-1000Hz) with pre-trigg" to capture the interesting part of the test.
How can I do this with DIAdem ? (Is Trigger-Sequence out of the quest ion?)
If in your application it is necessary to have a pre-trigger the Trigger-Sequence is not the best choice. Attached you find you DAC-Scheme with some small modifications to solve the problem (I hope). I'm working with a second clock, a Copy-Block and start-/stop-trigger for the Save-Block. In the Save-Block I used the parameter "Retrigger".
I hope you can use the principle in you application.