Saving data

[pnam]

Hello,

I am contineously acquiring analog data from 4 channels. I would like to save data (certain number of samples) every time a trigger ( a digital input) is acquired .

What will be the best way to go about doing this?

Any leads or example codes will be highly appreciated.

-Priya

[Mark_Ramsdale]

Have a case structure that , when the trigger is acquired, will save your data to file.

Open a file outside the Acq. loop.   Put the "trigger case" inside the loop.

Can you show the Data Acq. loop you have?

[pnam]

Sorry for the delay in replying. I have attached the screen shot of the different loops.

The loop which has the digital trigger is Digital Trig.JPG

The analog data collection is in a different loop  (Analog Data Collection. JPG)

I would like to save the data in the format shown in Save Format.JPG

[pnam]

Here  is the labview code.

[Mark_Yedinak]

You don't specify what rate you are collecting and trying to save data at. However, I recommend that you use a parallel task for saving your data. File I/O is slow and if you are trying to collect your data at a reasonable rate you don't want the file access stuff to impact your data collection. When you collect the data post it to a queue for further processing/logging. The logging task will get the data from the queue and then handle formating and writing the data to a file. If you are collecting at a high rate it can be useful to bufer up the formatted data and write it to disk at periodic intervals.

[Mark_Ramsdale]

Hi,

Can you restate , related to the VI's you have posted, what exactly your question is.   I noticed you have a few event structures, and several loops, so it is hard to understand in specifics what you are having trouble with.  thanks.