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USB-6009 Loosing data when other USB items connected or CPU usage increased

I am having problems with a USB-6009 loosing data when the computer (Intel Atom based with embedded XP) has any increased usage or a USB item is connected. When we use a computer with an Intel Celeron with embedded Windows 7, it doesn’t show this problem but still randomly loses data. (I use a tester that generates an analog curve that we capture and process. By writing the data read from the NI driver after being read (NI function DAQmxReadAnalogF64), I can clearly see missing data.

 

However both systems loose capture data even though we are constantly reading in a dedicated thread, only reading the data via DAQmxReadAnalogF64 and putting it into a queue. Other threads handle the processing of the data. The program is a service along with a GUI applications use very little CPU (around 0-10%) Written in C++ using the C++ NI API.

 

The problem can be easily recreated on the Atom based computer by plugging in a USB drive or Keyboard which causes the data lost.

 

The NI buffer is set to 100,000 samples and we are running two channels at 20,000 samples per second each.

 

Any idea how to prevent data loose which appears to be coming from the NI drivers?

 

Thanks

Sheldon

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two thing I could indicate
1 use back usb port they have less noise than front usb port
2 you have two rate
sample to read
rate of acquisition
you have to change and increase your sample to read until you did not loose any data
for example if you choose 47000 rate and 200 sample to read may be your system cpu could not work with this speed of cycling so increase sample to read 1000
but you have to we aware that your RAM do not overflow with increasing of sample to read
if you could not find suit sample to read
it show that your system could not work with this rate and you have to reduce your rate

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