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i am using acquring and process N scans Vi for acquring data from 6 channels but my system becomes slow as it has to be configured everytime so please suggest any other way of doing it

i am using acquring and process N scans Vi for acquring data from 6 channels but my system becomes slow as it has to be configured everytime so please suggest any other way of doing it
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It sounds like you want continuous acquisition; as you say, acquire and
process is not suitable due to the initialisation overheads at the start of
each cycle.

What you need to do is call "AI Config.vi" to set up the DAQ, then call "AI
Start.vi" to start the acquisition. You then need to periodically poll "AI
read.vi" to retrieve either n new datapoints or, alternatively, all the data
recorded since you last called the function. When configuring the DAQ, make
sure you allocate enough buffer storage for the DAQ to write into between
successive calls to AI read, and make sure long-term that the program is
able to keep up with the DAQ rate- if the buffer fills up then you lose all
the data in there, and though the DAQ continues and you can carry on reading
after the t
ransient error, you then have a gap in your data of an uncertain
length due to the lack of timestamps.

If you are accumulating data using AI read and then dumping it to disk
periodically you may find the use of a circular buffer improves long term
reliability, since you just use the same bit of memory over and over again
rather than periodically allocating and deallocating blocks, which in the
long term can lead to memory fragmentation and decreased performance.

Once your program finishes, make sure you call "AI Clear" to reset the DAQ
software.

vicky wrote in message
news:50650000000800000060290000-993342863000@exchange.ni.com...
> i am using acquring and process N scans Vi for acquring data from 6
> channels but my system becomes slow as it has to be configured
> everytime so please suggest any other way of doing it
>
> i am using acquring and process N scans Vi for acquring data from 6
> channels but my system becomes slow as it has to be configured
> everytime so pl
ease suggest any other way of doing it
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