Error -200279 occurred at DAQmx Read

[BRO8]

Hi,

I am having trouble understanding the timing issues that I am having with the DAQ vi's. As I run this VI, it wites the changes to the oscillatory Analog Output about half the time. When It works, I receive the error message:

Warning 200015 occurred at DAQmx Write

While writing to the buffer during a regeneration, the actual data generated might have alternated between old data and new data. That is, while the driver was replacing the old pattern in the buffer with the new pattern, the device might have generated a portion of new data, then a portion of old data, and then a portion of new data again.
Reduce the sample rate, use a larger buffer, or refer to documentation about DAQmx Write for information about other ways to avoid this warning.

When It does not work, I receive the error message:

Error -200279 occurred at DAQmx Read

Attempted to read samples that are no longer available. The requested sample was previously available, but has since been overwritten.
Increasing the buffer size, reading the data more frequently, or specifying a fixed number of samples to read instead of reading all available samples might correct the problem.

Although with these errors the program works more or less the way that I want it to, I would prefer it succeed in each iteration rather than every-other interation. I attached the VI that I am having these problems with. Does anyone have any ideas?

thanks,

brendon

[Jake_G]

Hey BRO8,

For the 200015 warning, the problem is the data being output is a mix of old and new data.  The solution to the discussion forum located here has some excellent information as to why this is occurring, as well as configuring the output buffer.

As for the -200279 error, this error occurs because samples have been overwritten by the DAQ card.  There are several solutions, and the knowledge base article Why Do I Get Error -20079 from my DAQmx Read VI or Property Node? has instructions to help with this issue.