Digital I/O

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Physical trigger for a pulsed UV Laser

I am currently working with the NI PCIe-6259 card which is connected to a BNC-2110 board. The goal would be to control a pulsed UV-Laser which emits in the range between 10-1000 Hz. Therefore I need a trigger because the laser emits accordingly to the trigger signal repetition rate. I just tried to create a digital trigger signal which switches between 0V and 5V with the frequency I would like to have. Unfortunately LabVIEW always shows error-200303 that says that an external source is needed (I added a picture of the blockdiagram.). Furthermore I tried an example which was already discussed in the forum ( Trying this didn't lead to an error message but I couldn't measure any signal. 


Does anyone have an idea how I can create the trigger better or see a possible mistake I made?


I would appreciate your help.




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The error message is correct -- on an M-series board, correlated digital output requires the use of an external sample clock.


The thread you linked has an example that creates such a sample clock using one of the counters on the M-series board.  That's why it can run without giving the error you had in your code.  However, that example also made use of triggering and I'm guessing you left that part in while not supplying an actual trigger signal.


For your usage, I'd take that example, change the counter task to be continuous, and get rid of the two trigger configuration calls right after the timing call.  I think that oughta work for you.




-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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Hello Kevin,

thanks for your answer. I've just tested it with the oscilloscope and now it works :).


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