Generate a harware trigger from incoming analog signal at specified level

Hi
I want to generate a hardware trigger at the counter out of my DAQ device from a incoming signal. As soon as the incoming signal crosses a specified voltage I want to get a trigger at the Counter out of my DAQ device.
Thanks
Manish

Dear Manish,
If I understand you correctly you want to create an analog trigger on a counter output line. Which DAQ device are you using?
You can't do this directly in hardware, but it can be done with the Analog Comparison Event line. Create an analog input task with an analog trigger. (There is an example of how to do this in the Example Finder. In LabVIEW go to the Help Menu and click Find Examples. Browse Hardware Input and Output>>DAQmx>>Analog Measurements>>Voltage>>Cont Acq&Graph Voltage-Int Clk-Analog Start.vi.) Before this task route the Analog Comparison Event line to a PFI line using DAQmx Connect Terminals.
Then perform a counter output task with a digital trigger. (Example Finder. Browse Hardware Input and Output>>DAQmx>>Generating Digital Pulses>>Gen Dig Pulse Train-Continuous-Dig Start.vi.) Wire the PFI line that you connected to the Analog Comparison Event into the digital trigger source input.
Hope this helps! Have a great day!
Sincerely,
Marni S.

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Message Edited by DiscoBall on 03-27-2009 12:12 PM
Message Edited by DiscoBall on 03-27-2009 12:13 PM
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Attachments:
compare.jpg ‏27 KB

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Generate a harware trigger from incoming analog signal at specified level

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