how to time stamp x-axis

[staggerlee]

hi,

i have a vi that every 5 minutes reads a set of data from a text file generated by another application, those values are then writen to a set of strip charts.
what i'm trying to do is get the x-axis of the strip charts to be the real/system time, so for the first value you get T1 as the x-axis marker, fo rthe second value you get T1+5minutes etc etc.
so as time goes on you can see several hours worth of data on the chart and view more via the history scrollbar.
i've tried setting the x-axis to system time, but just get 1904 etc etc.  x-axis offsets gve me the local time, but don't increment correctly. build waveform with dt and xo components gives me correct time stamps, but the chart doesn't update like i want.
any pointers help much appreciated.

cheers in advance, jk.

[tst]

You need to set the Offset & Multiplier properties. The offset should be the time when you start plotting and the multiplier should reflect the time between each 2 points as a number of seconds (in your case 300 for 5 minutes). Note that if your timing isn't exact, you will start to see some drift over time. One approach which can help in solving this is doing something like what's shown in the VI below. If this didn't help, you should post your code.