Instrument Control (GPIB, Serial, VISA, IVI)

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I can't select my USB-RAW device in the VISA ressource name box

Hi,
 
I have a problem reffering to the connection with an USB-device.
This device is called: ELV UM 100 (USB to RS-232 interface) and it's a USB-RAW device.
I have installed the .inf file with the help of the tutorial: Using NI-VISA 3.0 to Control Your USB Device.
The device is correctly installed, because it is shown in the Measurement Studio as an USB-device and
VISA Interactive Control signals the USB-device too.
Next I built up a programm in LabView 7.1, similar to the example in the tutorial.
I used the two additional VISA functions for USB, viUsbControlIn and viUsbControlOut in my programm.
I have already chosen the I/O session: USB-RAW in the VISA ressource name settings.
But I can't select the USB-RAW device in the VISA ressource name box?!
There are only the COMx and parallel interfaces.
My programm should send a message over the USB interface to an RS-232 interface (microcontroller) and backwards.
I read the tutorial: How Can I Communicate With a Device Using NI-VISA USB RAW Mode? and the reference manual too,
but without any success.
How can I etablish a connection to my USB-RAW device?
Which settings can a select in the USB session window (template, basic I/O and interface I/O) in the VISA Interactive Control?  
I'm very pleased, if you could send me an example program.
My operating system is Windows XP, Service Pack 2.
The attachment contains the first version of my program.
Thanks in advance,
Georg Mayr
 
 
 
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I believe the I/O control in LabVIEW only shows ::INSTR sessions and aliases. If you have a ::RAW device that doesn't have an alias it will not show up.

Options:
1) Type in the name of your device as it appears in MAX.
2) Create an Alias in MAX and it should then show up.


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If it's a USB-Serial converter, you do not create an inf file and use it as USB Raw. You use the driver that comes with it to make it appear as a com port. The device should appear in MAX as Comx and you use VISA Reads and Writes to talk to your device just like any other serial port.
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There is now an additional option. Use LabVIEW 8.0. In LV 8 we added a feature to allow I/O name filtering for the VISA I/O Control. This allows you to select any VISA class or bus type to show up in the list. You could change the settings to show everything (Serial, GPIB, USB RAW,...) or you can now limit the list to just USB RAW. Just right click on the control to change it's class or select the filtering. It is really cool and nice to have. Try it out and let me know what you think.

-Josh
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Thank you all, for your help, reffering to my problem.

The advice to create an alias was very helpful. Now the USB device is shown in the VISA ressource name box.

But if i start my program, the USB device will be found by all ressources (COMx and parallel interfaces)?!

Although it is only connected over the USB interface.

Now to your answer Dennis Knutson:

I have used the driver that comes with it. The device manager showed a virtual COM-port. 

But in this case I got during the data transfer the error messages, "frame error occured during transfer" and

"couldn't perform operation because of I/O error".

Although all settings are the same (Baudrate, ...)

Thanks in advance for an additional help,

Georg Mayr

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