Setting a network shared variables timestamp

[BillMe]

I am taking readings from an instrument that supplies its own timestamp. The data is sent via an NSV. Can I "set" the NSV timestamp with the one from the instrument.

I see no way to set it and suspect it is set by the PSP server when publishing the NSV, but I thought I'd ask.

LabVIEW 2018

[GerdW]

Hi Bill,

no, you cannot set the timestamp of the NSV to an arbitrary value.

(IMHO it takes the timestamp of the last write operation to your NSV…)

[Bob_Schor]

If the Instrument is supplying an accurate Time Stamp, why not include it as part of the data being sent?  It is generally a "bad idea" to "falsify" data, as it can tell you about the "state of your instrument".  In the Best of All Possible Worlds, the TimeStamp from your Instrument (which you believe is accurate) should closely match the TimeStamp associated with the NSV -- they should agree to a few clock ticks, and the delay should be constant.  You could monitor this and potentially get an indication that the system sending the NSV might be doing something that you don't expect that causes the two TimeStamp differences to change, which might indicate a problem in your system.

Bob Schor

[BillMe]

We have several systems logging data where the systems get their time from a precision time source using PTP. This is to get the best data correlation across log files as possible. The instrument does not support this protocol but I can set its time at initialization from the PC system. Since I don't know how accurate it is or how much it can drift, I have opted to ignore the instrument timestamp and instead use the NSV timestamp which at least is sync'd to the PTP server (thus sync'd to the other systems).