Measurement Studio for VC++

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StartTask and time elapsed

Hi

Is there a way to know the time alapsed between the DAQmxStartTask's call and the real beginning of the acquisition ? Or is it simultaneous ? (I'd like to know exactly the date and time of each mesure).

Thank you
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Hello PeteBull,

The acquisition begins when you call DAQmxStartTask. In facts, there may be a very small delay. What do you need in terms of precision? Which DAQ hardware do you use? See the user manual of you acquisition hardware for further details about timmings.

Cordially,
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Hello

I'm using a NI-PCI-6132 and I'd like a precision of at least one millisecond.

Cordially
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Hello,

Unfortunately, the delay is system dependant. The driver can assure the time interval between samples, because they are clocked. But there is no timestamp for the first sample, except, perhaps, calculate the timestamp of the first data transfert to memory.

Moreover, under Windows, you will not be able to get a better precision than about 10ms (it is not a determinist operating system).

Cordially,
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Hello

I think it will be enough, I need a precision less than 100ms. I'll check the first data transfert to memory to be sure.

Thank you


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