USB-6501 command set

[Malcolm]

We do not currently have a DDK for the USB-6501.  The complicated part is documenting the internal communications protocol.  It does not conform to the USBTMC standard or use SCPI (IEEE-488.2) style commands.  It instead uses VISA Raw to communicate at a very low level.  The best option would most likely be to use NI-DAQmx (as Dennis mentioned).
I'm curious why NI-DAQmx does not fit your control application.  What is it that you are trying to accomplish?  How many of these devices are you using?  Are you just trying tom use a simpler programming interface?  Is the rest of your system using GPIB-style commands?

[MarcVB]

I am also looking into the purchase of USB-6501 but I also want to program it via VISA USB. The reason is mainly because I want to integrate it into an instrument that has its own PC with a LAN connection. It should be possible to address the USB-6501 from an external PC through that LAN connection in a transparent way (same software as on the internal PC). The idea was to go via VISA LAN, in a similar way as one can control GPIB instruments via LAN, having the LAN as a transparent communication,
 
Marc Vanden Bossche
NMDG Engineering

[Jennifer O]

Hi J^T,
Malcolm's post is still valid;&nbsp; USB currently is not supported under MHDDK (Measurement Hardware Driver Development Kit).&nbsp; I invite you to submit a product suggestion <a href="http://digital.ni.com/applications/psc.nsf/default?openform" target="_blank">here</a>, which will help to show the demand for USB DDK support.
&nbsp;For information and support on DDK, visit the <a href="http://forums.ni.com/ni/board?board.id=90" target="_blank">DDK discussion forum</a>.
Regards,
Jennifer O.Applications EngineerNational Instruments
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[Jennifer O]

Hi MarcVB,
With DAQmx 8.0, the ability to use OPC to communicate with DAQ on a remote machine was introduced. See <a href="http://zone.ni.com/devzone/cda/tut/p/id/3742" target="_blank">Using the LabVIEW Shared Variable and OPC With NI-DAQmx</a>&nbsp;for instructions on how to set up communication.&nbsp; In LabVIEW 8.0 (or later) the shared variable can simply be read to retrieve the data from the remote computer, however LabVIEW is not required.&nbsp; You can&nbsp;also use a third party OPC client to connect to the variable engine server. <a href="http://zone.ni.com/devzone/cda/tut/p/id/3259" target="_blank">Developing an OPC Client Application Using Visual Basic</a> is a good resource to reference for creating an OPC client in a text based language.
Hope this helps,
Jennifer O.

[Jennifer O]

Hi Marc,
&nbsp;
Remote systems are generally used for FieldPoint or remote VISA sessions.&nbsp; DAQmx is not supported in this way.&nbsp; To use DAQmx remotely, you must create the Global Virtual Channel.&nbsp; The Global Virtual Channel is then made available to the network through OPC.
&nbsp;
Regards,
&nbsp;
Jennifer O.