Rate of Obtaining Data

Question

Hi everyone,
I have recently constructed a VI which obtains data from a DAQmx, and saves it to a log file, a long with the time duration of the test (Hence the Elapsed time VI).
The data saves to a immediatley a file, which can be analysed later using the same software.
The problem i seem to have, is that the data seems to save every 19 msec, yet I need it to be roughly 1msec or quicker. From things i have read on the forum, the constant saving of data directly to a file is what is slowing my code down, yet i can't seem to save the full 30 seconds worth of data to an array and then export that to a file once my data collection has finished.
The max length of a data sample would be 120 secs (ie 120,000 data points).
Here is a snippet of the data aquasition part of my code.
Any help would be greatly appreciated.
Thanks,
Oli
Solved!
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Answer 1

If you can write to the file after acquiring the data, then that simplifies your solution.
Since you know the number of samples that you expect, you could initialize an array to a size slightly larger than the size to accommodate all your data and then write (insert) into that array.  You would pass the array around the loop using shift registers.  After the While Loop, you would write the entire array to file. 
Place a 1ms delay within the While Loop.  If your loop actually takes 1ms to obtain (read from DAQmx), then a little trick would be to set the value of the Delay to 0ms.  Yes zero.  0ms will still allow the processor to handle other tasks, although the CPU will show high % useage.  It is different than not having a Delay at all...
And get rid of the Elapsed Time..