How to Only Save One Data Point Each Second

[Chris_VH]

Overview

Code that shows how to log data every second on a LVM file.

Description

Many applications take more than one data point per second. But sometimes, only one data point per second is necessary to log due to such small change in the data. Obviously the one "per second" is arbitrary, and could easily be replaced with one per minute, per hour, etc. But this program does one per second.

The VI builds an array of random numbers (obviously not the most memory efficient, but fine for this simple program). It will then take an input of Hz, which is also used to calculate the time for the wait function. It then takes the remainder of the iteration count and the desired value. When that equals zero (meaning its a multiple of the Hz input, or on the exact second) it will log that data to OneValuePerSecond.lvm on your C drive.

You will notice in the first column (time) of the lvm, that the seconds will start becoming non-exact. This is due to the software timed nature of this particular program. If your application requires exact timing to the second, than this program is not for you. However, if you are looking to free up some memory in data logging, or save yourself some time in looking through all your data, this is for you!

Requirements

LabVIEW 2012 (or compatible)

Steps to Implement or Execute Code
1. Configure the Hz to sample. Currently is set to be for 1 sec.
2. Select the path where the file will be, with the name of the file.
3. Select the Run button.

Additional Information or References

 

[j_paiz]

Is there a way to modify this example to use data from two RTD temperature sensors that I am working with?  I get an error just before the convert to dynamic data function saying I have wired two different data types.   

[j_paiz]

[j_paiz]

There is a picture of the block diagram I am trying to work with.  I want to add a producer/consumer loop eventually but for now I was just hopeful that I could get the RTD to log every minute or so. 

Also if there is a better way to post my .vi please let me know

Thanks in advance  

[j_paiz]

Ive attached my updated .vi where I seem to have worked out my above problems.  Does anything in my .vi raise any red flags??

[j_paiz]

This one ^ writes to the data file every 180 sec (5min)