Senescence of data (data age)

[caunchman]

  Hey All,

     I am currently using a DAQ 6015 set up to monitor 4 analog voltages that range from 0 to 5 V.  I set the channels up using the DAQ Wizard in a basic While loop, and they are set to record at 6000 Hz and 1000 samples to read.  These signals are being picked off various transducers.  I am displaying these values and also writing these values to LabVIEW .lvm file using the file wizard.  My question is, Is there anyway of determining of how old the actual data is that I am writing to file? How accurate should may results be?

Thanks,

Chris

[DFGray]

If you fetch your data using the waveform datatype, the timestamp will tell you when the data was collected.  The absolute accuracy of the timestamp will be no better than the clock setting on your computer.  The relative accuracy will depend on your hardware.  I do not know whether or not E-series devices have hardware relative timing (I think they do not), in which case your relative accuracy will be on the order of 100ms due to the operating system.  If they do have hardware relative timing, it will be on the order of the base clock period with further long-term errors due to clock jitter and drift.

How much accuracy do you need?