Signal Express- error 200279

[cek]

This is more of a recommendation than a question.  I have been having a very bothersome issue with error code 200279 running SE under Vista on a pc with 4 g memory.

In frustration I added a 16 g memory stick ( with cruzer or ReadyBlast features) and run it under Vista ReadyBlast option.  Guess what, no more error codes 200279. I suggest you note this as solved.

[BCho]

Hey cek,

Are you doing a continuous read using the DAQmx driver by chance? Error code 200279 refers to a buffer overflow error where you are placing data on in the buffer faster then you are taking it off of the buffer. So, another way to address this issue is to look at the rate at which you acquire data and the rate that you bring that data into your program. Take a look at this Knowledgebase for a little more information on this particular error code. Adjusting these rates can be another way to address this particular error rather than having to increase the RAM of your system.

Hope this helps,

-Ben

[cek]

Hi Ben,

I have adjusted the size of the buffer to be 1/10 of the samples per sec. It is not entirely clear under SE how to set that buffer size, but I assumed it to  be number of 'samples to read'.  Right? 

[cek]

Much to my frustration, the error code 200279 is back even with the memory stick.  Some times I can run and log many files with no issue, then the error re appears and it almost appears to require re start of the PC. Any suggestions on either SE or the PC side that would help?

cek 

[Coq_Rouge]

Hi

The buffer is a temporary storage used by the daq unit to store samples. It is from this buffer you draw your samples. Not from the daq unit directly. If your buffer is filled up faster than you read from it. You will experience a buffer overflow, and corrupted data readings. The solution may be to increase the buffer size. But if the buffer is filled up faster than it is read, you will in any eventuality experience a buffer overflow. My guess is that you have a flaw in your code, causing the buffer overflow. If you post your code here you will get the help you need. 

[BCho]

Hey cek 

The buffer size is something that is normally done automatically by the DAQmx driver. This actual buffer size is mainly based on the sample rate you are using. The number samples you read simply tells the software how many samples to grab from the buffer. The proper number of sample to read is largely dependent on your sampling rate and the rate at which your loop runs. If you have a lot of steps in your loop you may not be taking all the available sample from the buffer each time through the loop and you will eventually fill the buffer and run into the error you are seeing. Check out this Knowledgebase for a little more information on how the buffer is set up. To try an eliminate this buffer overflow error, I would suggest sampling at a slower rate or increasing the number of samples to read.

Hope this helps.

-Ben