Generate AO with Digital trigger

Hello, I am having trouble outputting a continous waveform (custom multlisample channels) when a TTL - like 5V 0V trigger is applied to PFI0. The trouble is although the timing source runs continously, when the digital voltage line is connected I get only one waveform sent out, as opposed to a continous regeneration of the same waveform.
I have been working with some conditional loops, but to no avail, is there a solution that can provide two triggers ( one for a pulse train) and then for the digital falling edge (on at 0V) that can allow for regeneration of the AO write?
Thanks,
DB.
Solved!
Go to Solution.

Hi DB,
A good example for this application is a DAQmx shipping example in LabVIEW. In LabVIEW, navigate to Help»Find Examples»Hardware Input and Output»DAQmx»Analog Generation»Voltage»Cont Gen Voltage Wfm-Int Clk- Dig Start.vi.
You can choose to specify an external clock if you would like by right-clicking on your source input to the DAQmx Timing and selecting Create»Constant. You can then specify where you bring in the external clock. By default, it will use the onboard clock of your DAQ card to create a pulse train. This example uses the parameters of the waveform to drive the sample clock timing.
What NI DAQ hardware are you using? By default, the card will store the waveform you wish to output otno the FIFO of the board, and regenerate the the waveform until you press the stop button. Does this help?
Best,
Adam
Academic Product Manager
National Intruments

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Hello,
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implement a schmitt trigger.
Struggling with Labview wrote in message
<[email protected]>...
>I am only a Lab View toddler.
>I am currently using a push button, wired to PFIO/TRIG1 and DGND, with
>a anolog trigger. However noise is causing my program to be triggered.
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How to use digital trigger with analog I/O

How do I program analog input and/or analog output to start on a digital trigger (PFI pin) on PCI-4451/4551.
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http://digital.ni.com/manuals.nsf/websearch/6A32358C53BB15F086256660007392DC?OpenDocument&node=132090_US
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Joe
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Attachments:
Route_RTSI_to_Source.vi ‏67 KB

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complementary test 2.vi ‏69 KB

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Go to Solution.

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Trigger_acquisition_test2.vi ‏23 KB

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