DAQ control from Python under Mac OSX

[jeffrodman]

I am creating a Python extension module for the USB-6008 under Mac OSX 10.4.8, and upon import into Python, receive a "failure linking new module; symbol not found _DAQmxBaseStartTask", with diagnostic "expected in dynamic lookup." I assume I'm just missing the directory in the environment path, but have not found where this resides. Can you advise where this should be pointed (and if possible which environment variable should be pointed there)? Thanks.

[MickeyD]

Hi jeffrodman,

I am sorry to say that Python is not a supported language for the DAQmxBase driver.  There are some customers that have gotten our devices working on DAQmxBase to work in Python.  All the ideas I have heard about using it center around making code that works in LabVIEW and then building a LV DLL.  You can call this DLL from Python, and that should not be to difficult to get working.  I will see if I can pull up any info about how you might set up the enviroment variable pointing, but I doubt there is a lot of information to be found.  I will let you know if I find anything, but just want to emphasize nothing I say is guaranteed to work, because non of our hardware or software was tested to be used in the python programming language.

Have a great week,

Michael D
Applications Engineering
National Instruments

[rjb3]

This message is going waaaaaay back to mickeyD. I've found a DAQmxBase wrapper and am attempting to use it but getting an odd error. Since this post have you heard more about people using python successfully? 

I posted the question below to the daqmx forum. 

Hi all,

Very new to this group. I'm also new to Python and Macs. I'm running NIDAQmxBase v3.7.0 on a Mac OS X. The version of Python I'm working with is 2.7.

I have a Python wrapper for DAQmx working in Windows and am trying to get something running on the Mac.I've run the mxbaseconfig and nidatalogger programs without issue. I've got some wrapper code that seems to be working right up until a call to DAQmxBaseReadAnalogF64 at which point it raises the following:

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

  File "NIDAQmxBaseWrapper.py", line 140, in read

    ctypes.byref(nRead),None))

  File "NIDAQmxBaseWrapper.py", line 77, in CHK

    raise RuntimeError('nidaq call failed with error %d: %s'%(err,repr(buf.value)))

RuntimeError: nidaq call failed with error -1073807346: 'VISA Write in Flush_Visa_USB.vi->USB-92xx Read Helper.vi:2460003->DAQmxBase Read USB-92xx(Analog 2D DBL NChan NSamp).vi:5700002->DAQmxBase Read (Analog 2D DBL NChan NSamp).vi:710001->DAQmxBaseReadAnalogF64.vi->DAQmxBaseReadAnalogF64.vi.ProxyCal ler'

Do any of you have any insight into where I'm going wrong?

Thanks very much!

Rob

[LindsW]

Hi,

If you have not already done so, you may want to repost this question to the MultifunctionDAQ board (http://forums.ni.com/t5/Multifunction-DAQ/bd-p/250) in a new thread.  A lot of times with posts this old, the original authors are not monitoring the post anymore, so you may have better luck starting a new thread.

Regards,