How can I save first data before data logging in a regular period?

[DiegoSV]

Hi,

I need some help to see what's wrong with my VI. I want to save the first data when I launch my VI until reach the first minute, after I want save data minute by minute, but in this fisrt period my VI does't save this data in the .lvm file.

Could someone help me?

Thanks.

[AdnanZ]

Can you explain again what exactly you want to achieve. You want data logged at 0min, 1min, 2min? Or at some other frequency?

[DiegoSV]

Yes. I'd like to save my acquisition data in a certain period of time, like you have said, 1 min, 2 min.......or 1 hour, 2 hour...whatever the user choose., but I'd like to save it always in full time and the data that correspond this period.

I'm using shift registers to do that, but I can't save the first data, i.e., when I started save the collected dat in 15:58:30, this data will be saved together with the next minute (15:59:00) and I would like to save this data separated.

I've attached the VI actualized with shift registers.

Thank you for a while. 

[MoReese]

You can place another case structure within your existing case structure (see attached).  The Write to Measurement file will not take place on the first call.

[DiegoSV]

MoReese, 

Could you post in the latest versio? I'm using LabVIEW 8.6.

Thanks.

[MoReese]

Try this.

[DiegoSV]

Thanks MoReese, but I can't open again. Well, I think I figured out what you have said last post and it worked fine, I will attach the new VI. So, I got another question right now. Why when data acquisiton has start collecting data with timestamp after some time it's incremented 1 second in the time stamp inside the lvm file or same in txt file? I'll attach the file to exemplify.

Thanks for the responses.

Diego 

[MoReese]

I am not sure what you are asking, but it looks like you are collecting data on a 1 second interval.  What does "Untitled 3.vi" do?

[DiegoSV]

Untiled3.Vi was a changed elapsed time.vi, now I came back to the original again. So, what I want the VI do it´s doing, which is saving data in this way:10:00:00,10:01:00....10:50:00
What´s going wrong is that after some time it increment 1 second, another period of time , one more second and so on. For example, 10:00:00.....10:10:01......10:30:02

[DiegoSV]

What can I do to avoid this?

Thanks.