USB-600x under linux using NI-VISA in TMC mode

[Adam Szpakowski]

Hello,

I'm trying to use NI USB-6008 device under linux using NI-VISA (4.0 version). Unfortunately the device is only recognized by visaconf as the RAW, not the INSTR one. Is there a way to talk to this device using USBTMC mode (this mode seems to be necessary for using PyVISA library). I'm able to open/close/get attributes using vpp43 from PyVISA, but if I understand correctly, anything more requires INSTR mode.

Best regards,
Adam Szpakowski

[Dennis_Knutson]

Why are you trying to use VISA? It's a DAQ device. For Linux, support is available with DAQmx Base.

[Adam Szpakowski]

I intend to use the device from python. The visa (and PyVISA) seems as a quickest way to do it.
So, there is a question... is there a simple way to use the USB-6008 under VISA in TMC mode or the faster/proper way will be to create the skeleton wrapper for NI-DAQmx Base library for python? Mayby there are such a bindings created with swig or boost?

[Dennis_Knutson]

Since the USB RAW protocol is not published by NI, you have to use DAQmx Base. I have no familiarity with Python but surely it can it not call an external DLL?

[Matthew_W]

 Hi Adam,

 There is article here which discusses creating a USB .inf file for communications with a USB device. There is a section near the end for Linux support, this might be helpful.

 The problem I think you will run into is there is not a published set of VISA commands for communications with the USB-6008.

 This discussion forum is focused on getting a USB-6501 to work in a similar fashion (communicating through VISA) , the issues they are experiencing should be informative as to your own effort.


 Take a look at this article, it uses ctypes and numpy to perform data acquisition using our NI-DAQmx library. This really looks promising.

  Another way be to use Python to make TCP-IP calls into a Labview program. Here is an external example.


Best regards,

MatthewW
Applications Engineer
National Instruments




 

Message Edited by Matthew W on 08-06-2007 11:27 AM

[Adam Szpakowski]

Hello,

Thank you, for information. Now, I do understand, that trying to get VISA to work is hopeless task.

Unfortunatelly, after two days of trying to get the device to work, I had no more spare time and moved to another solution (and unfortunatelly different DAQ device). Maybe in the future I'll try again to use NI USB devices under Linux, but for now the support is too limited. For now, the quite annoying installation process of the NI-DAQmx Base under the distribution which is not officially supported (Gentoo) was extremally frustrating and to time-consuming.

Best regards,
Adam Szpakowski