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Running 2 PCI-6115 4 Channel Analog Input on DAQmxBase15

I am using DAQmxBase 15.0, 64Bit on CentOS-7.0  I have 2 PCI-6115 with 16Ms FIFO's.  So far I am only able to run 1 card in continuous mode at 10Mhz.  I have tried modifying the simple program at /usr/local/natinst/nidaqmxbase/examples/ai contAquisition.c.  I changed it to run at 10Mhz, all 4 channels.  If I run 1 copy of this program on Dev1:ai0:3 it works fine.  If I start another copy pointing toward Dev2:ai0:3 it runs for about 3 seconds than 1 or the other of the applications die, with an error 42, or other error, usually indicating the FIFO or memory buffer is not large enough.  If I drop the speed of both to 5Mhz they run just fine and forever.  

This is on an 8Core XEON, with 8Gb memory, so I doubt the processor speed is an issue.  

I have tried every avenue to get this to work.  Any advice if this is even possible, or flags, to get this to work is appreciated.

-thanks,
Michael

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Hello, 

 

I think you may increase the number of samples your daqmx timing vi can support.

Let me know the results after this step is implemented 

 

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Thanks, but I am not using a vi. This is a C program.  I have tried many sizes of samples to read, from very small (12,000), to very large (125,000 which seems to be the max DAQmxBase 15.0 will support.

 

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