Does LabVIEW supports all IEEE cards or just NI IEEE cards?

[Elsa Fung]

Hi!  I have an IoTech IEEE Card connected to a switch test unit.  I found the LabVIEW driver for the switch test unit, and I just want to know if it matters whether I use IoTech IEEE card or National Instrument IEEE card.  And if someone knows, can you tell me the difference between the two IEEE cards other than they are from different manufacturer?  I'm pretty new to LabVIEW and data aquisition in general.

Thank you!!

See-Ming Fung

[Dennis_Knutson]

Yes, it matters. LabVIEW has two different methods for GPIB communication. There are the VISA (Instrument I/O>VISA palette) functions and the traditional GPIB (Instrument I/O>GPIB) functions. VISA is a higher level API that can be used for GPIB, serial, ethernet, USB, etc. instruments. VISA is an industry standard and all new instrument drivers use VISA for communication. If your card has a VISA driver for it, then you can install that and a VISA instrument driver will work. The traditional GPIB functions are only for NI cards and any driver that uses them, will only work with an NI board. Some vendors supply a driver that replaces the NI functions or they supply a board that is compatible with the NI GPIB boards. I have never used an IOTech GPIB board so I don't know what they do. You should check with them about LabVIEW compatibility.

[Elsa Fung]

Thanks!  That clarifys a lot of question I had in mind.  Unfortunately after researching on the IoTech card, I found out it does not work with VISA (and of course, the driver I found for the switch test unit needs VISA!!).  But, luckily, the IoTech card is compatible with LabVIEW (harray!), I just have to use the complicated traditional GPIB functions instead super convenient downloaded drivers.

Thank you!!

See-Ming

[jdebuhr]

Another thing with the IOTech cards is that when doing IEEE 488.2 commands you need to set the LabVIEW traditional Vis in Synchronous mode, I don't think they will work in Asynch but I have not tried it recently. We have a Couple IOTech cards here where I am and I wish we could replace them all with NI cards.

[Dennis_Knutson]

The drivers can be converted to traditional GPIB calls with a little work. You can replace each VISA Write with a GPIB Write and each VISA Read with A GPIB Read. Instead of a VISA Resource Name, you replace that with a string for the address.

[Elsa Fung]

Really?  That would be great!!  I'll try that!

Thank you so much!!

See-Ming

[rolfk]

Well VISA is only partly an open standard. Basically the part which is standardized about VISA is the API to the application level. Any application should be able to use any VISA implementation. The problem is that there is mostly only one real VISA implemenation (with maybe HP having its own). All other VISA implementations are just relicensed NI-VISA implementations.

NI-VISA uses internally a plugin architecture which allows the generic VISA32 API layer to interface to new IO channels. This internal plugin API however is not documented and therefore only NI is able to create new plugin drivers. This locks out any NI competitor from creating a VISA plugin to work with NI VISA. Supposedly you can license the NI-VISA software and companies like Tektronix have done that for their devices but I have some doubts that IO Tech would get such a license under terms they would find favourable.

Rolf Kalbermatter