Timestamp resolution

[xl600]

What is the resolution of the Get Date/Time in Seconds VI under LabView RealTime 2014 on a PXIe-1082 platform with a PXIe-8135RT controller?  I gather from various posts that this is about 1us.

In experiments comparing the high resolution timer to the basic timestamp returned by the Get Date/Time in Seconds, they appear to be basically the same to within 1us over quite long periods (Hours).  So I'm thinking there's no real need for the high resolution timer functions or anything fancier like a 6683H or 6672 if my timestamping accuracy requirement is in the us range.

Is there any white paper or document which directly speaks to the timer resolutions and expected accuracy of timestamps which are hardware dependent?

Thanks,

XL600

[VItan]

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@xl600 wrote:

What is the resolution of the Get Date/Time in Seconds VI ... I gather from various posts that this is about 1us.

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Your gatherings are in error.  The resolution of the datatype returned by the Get Date/Time in Seconds function is 2^-64 seconds.  It's still possible for a platform to only populate the datatype at a certain resolution different from the maximum allowed by the datatype, so the pure datatype resolution is not the only relevent bit of information; however, I have seen sub-microsecond resolutions recorded in LVRT.

Now, as for accuracy and precision...

[xl600]

That is what I was referring to, sorry.  The resolution of the datatype is the fractional seconds portion (U64) of the timestamp which is in the femtosecond range.  I'm looking for some definitive information on what a PXIe-1082, PXIe-8135RT, and LV RT will populate.  I wasn't able to find any documentation which details this.