Continuous Acquisition with HSDIO

[anncy]

Hello,
I am going to build a continuous acquisition program over NI-6541.
I plan to place dynamic acquisition function in a loop, but I'm not sure if there may exist gaps between each acquisition call.
Therefore, is there a better way to enable continuouse acquisition. Thanks.


Best regards,
anncy

[ryanm]

Hi Anncy,

If you have version 1.4.2 or later of the NI-HSDIO driver installed, there is a shipping example which shows how to continuously stream to disk using an HSDIO card.  This example will continuously stream data without any gaps, which seems to be the example you are looking for.  To locate this example, open the Example Finder and navigate to Hardware Input and Output >> Modular Instruments >> NI-HSDIO >> ContinuousAcquisition-StreamtoDisk.prj.  Please let me know if you have any questions.

Ryan

Message Edited by ryanm on 10-11-2006 08:16 AM

[anncy]

Dear Rynn:
Thanks a lot, your suggestion is very helpful.
After tracing ContinuousAcquisition-StreamtoDisk,  I have a question about the example..
During the iteration loop, it acquires waveforms and writes back to disk .
However, the program may suffer certain delay due to I/O operations. 
Does the cumulated delay affects aquisition operation?

Best regards,
Anncy

--

Well, I just tested the program.
If disk I/O occupies too much time, it may leads to error, "-200004: Data requested has been overwritten in the device memory."

由 anncy 在 10-11-2006 09:25 PM 上編輯的訊息