pre trigger for USB-4432

[Samid]

Hello, my name is Dimas aryo, student of Institut Technology of Bandung..I'm still doing my final project.. my hardware is USB-4432..I have succeeded to build Triggering program, and can start taking data at certain level ( 0.2 Volt )..but i'm still confuse how to see the data at certain seconds before start  taking data ( Pre-trigger ). I'm using DAQmx for the driver..and LabVIEW8.5..

Your help will be aprreciated.. better that you can attached it..

Thank you very much guys... GBU All...

[GarPar]

Hello Dimas-

     I think what you are trying to do is use a reference trigger.  From LabVIEW, select Help»Find Examples.  Once that opens, take a look at Hardware Input and Output»DAQmx»Analog Measurements»Voltage»Acq&Graph Voltage-Int Clk- Dig Ref.vi.  The digital reference trigger will wait until the number of pre-trigger samples has been gathered before it registers a trigger on the specified line.  At that point, it works like a circular buffer, continuously throwing away the oldest sample as the newest sample arrives.

     I hope this helps.  Best of luck with your application!

[Samid]

Hello Mr. Gary,I have tried using Reference analog edge and Reference digital edge for triggering, but the hardware of USB 4432  cannot respons anything for acquiring the data... i have tried with property node of trigger, and the respons still the same.. Is it possible that we can build pretriggering program manually without using DAQmx ? .....

Thanks for your helping and attention... Gud Luck sir...