Triggering an analog signal using USB6008

Hi I'm trying to use the start trigger with DAQmxBase acquiring analog signals with the USB 6008.
When i configure the trigger as Start Digital Edge I become an answer, but only starting at an rising edge.
I want the acquisition to start at a define level, so I've tried with Start Analog Edge, but the acquisition is stopped.
Can someone help me how to configure better than i do?
Thanks.
Regards
Patrick
Patrick Etoumann

Hi!
It's not possible to configure an analog trigger with an USB 6008 -> only digital trigger is available!
If you want to start on a predefined level then is the only option to do this with an analog-software trigger!
http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=C16B1501B4D9168DE034080020E74861&p_...
regards
ThSa
http://www.newgistics.com

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