I'm trying to control a Metex M-3890D (aka Voltcraft M-3890D) Multimeter via its USB-port.
I've created the *.inf-file using the VISA device driver wizzard provided by NI. After installation
the device is shown in MAX as USB0::0x0925::0x1234::NI-VISA-0::RAW and I defined
MetexUSBDMM as VISA alias.
By using an USB-monitor I've explored that "0x65, 0x65" has to be sent to the Metex via
control endpoint to request the data, which will be sent via Interrupttransfer.
Based on an example given by NI I wrote a small VI to perform the request, but all that
I get is an error message (code -1073807302, VISA: (Hex 0xBFFF003A) Unable to start operation
because setup is invalid (due to attributes being set to an inconsistent state)) or LabVIEW 7.1
crashes completly. You will find that VI as attachment.
My questions are:
What might be the reason for that error and how to correct it?
Is there anybody who ever used USB-raw communication within LabVIEW successfully and
could give me an example?
Thanks
Steffen