Computer running LabView loses time

[GP]

I have found a sort of fix to this in that I now read the time from a stable device (another pc with no time drift) through LabView (via a GPIB command). I can either timestamp this to file at each measurement or convert it to an elapsed time from start of program. This can be done by converting time to elapsed time from a referenece date (see labview) at program start and at each measurement. Then subtract the start time to get elapsed time.

This circumvents the clock lag on the pc running Labview (for the time being). I can't use the internet to
update correct time so this works for the moment.

GP

[GP]

I have found a sort of fix to this in that I now read the time from a stable device (another pc with no time drift) through LabView (via a GPIB command). I can either timestamp this to file at each measurement or convert it to an elapsed time from start of program. This can be done by converting time to elapsed time from a referenece date (see labview) at program start and at each measurement. Then subtract the start time to get elapsed time.

This circumvents the clock lag on the pc running Labview (for the time being). I can't use the internet to
update correct time so this works for the moment.

GP

[Mark A. Hanning-Lee]

Laurent wrote:
>
> My LabVIEW data acquisition application running under Win 98 also
> slows down my computer time dramatically. But I cannot envisage to
> restart the computer because it is a standalone application. Isn't it
> a way to force Windows time to BIOS time, with a process written or
> not in LabVIEW ? Thanks for your ideas.

Use Dimension 4 to go to the Internet, read the correct time, & reset
your PC clock. It can run at set intervals, or once on reboot.

Caution: it may disrupt the timing of your program if you reset the time
in the middle of a loop or of a timed delay!

Win2000 seems less prone to time-loss problems.

Also search zone.ni.com & NI developer zone for other references.

Mark

[GP]

Mark,


Thanks for that. This is one of the first Labview routines that I have written. I
realise it may be worth restructuring the routine to see if that helps. The routine actually uses frames to execute the serial and GPIB commands (with ms waits in each frame). This all happens in a loop which executes after a set wait (sampling) time.

789
Data is written to a file (size of which is set at start).


I'll try some different things. I'm puzzled by the fact that on another make of pc (Dell rather than HP but also with Win95), time drift doesn't appear to be a problem. Any thoughts on why different hardware behaves differently?


GP