DAQmx export signal

[Simon GB]

Hi,

I'm having a lot of trouble getting the DAQmx Export Signal VI to do anything.  I need to output both the sample clock and the AI start trigger from my PCI 6010.  According to MAX it should be fine to send these to any of the PFI terminals but I can't get anything out or any error messages (except when I route to PFI 0-6 which are reserved for the two counters by default).  I have attached one of the Labview programs I've been trying which as far as I can work out is correct.  I've also played around with the connect terminal VI with the same lack of success.  Does anyone have an idea what the problem might be?

Thanks in advance,

Simon.

[TheWay]

Hi Simon,

Your VI seems fine.  I'm using a PCI-6251 and running your VI exports the sample clock or start trigger fine.  Be aware that the pulse width of the exported sample clock or start trigger is only somewhere around 50 ns.  Make sure your scope or device receiving the trigger is fast enough to catch it. 

I hope that helps.

Way S.

NIUK Applications Engineer

[Simon GB]

Thanks for your reply and checking the program.  I didn't realise that the pulses were so short, I had assumed that the pulse duration would increase when the timebase is divided down to generate the sample clock.  I just tried monitoring the output with a bench top counter rather than a scope and managed to see the pulses.  For some reason I'm getting twice as many sample clock pulses as expected, but perhaps I haven't got the counter set up properly.

Thanks again,

Simon.