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Hi All, I have a small problem. A customer is running a system which does various things including acquire data from an agilent oscilloscope connected via Agilents USB interface (USB in the scope).The system and software were developed by another company, but the gist is, the software uses the Agilent IO library to connect to the scope, and that includes Agilent VISA. I now want to install and run a labview based program which controls a completely independent (at least in terms of control) device on the same PC. My system (written in LV8.6 and run from exe after installation with NI created installer) requires VISA to communicate (via a USB-RS232 adaptor - within labview I simply address the COM port which is installed by the adaptor). I ran my installer and my device worked fine, but the Agilent Scope then failed to communicate (Error message said : Unable to communicate with device USBInstrument1 on VISA (or words to that effect). The only way I managed to get the scope to work again was to re-install the agilent IO library. But then of course, my system no longer worked (Error 0xBFFF0012 Invalid resource reference specified. Parsing error). Initially, I could only get one version of VISA to install at a time, but I did finally mange to install the Agilent as the secondary VISA, but I still had the same problem with the Agilent scope not talking. Does anyone know of a fix for this kind of problem? I'm not trying to use labview to control the scope, only my other device, but I can't seem to get both things working at once! Any help very gratefully recieved. Paul

What version of LabVIEW are you using? As of 2009+ this should not be an issue - as the build structure has changed to avoid name collisions when building. Assuming the 8.x build option is unchecked and same-file-names are namespaced differently.

I recall that the Agilent GPIB interfaces need an extra piece of code / dll to be used from LabVIEW; I think it's referred to as a 'tulip' driver. I Googled and found some app notes on the Agilent site: http://www.home.agil...029&pageMode=AN Look at the document titled "Tips in Using Agilent GPIB Solutions in National Instrument’s LabVIEW Environment"

I would very much be against this. I try to follow every post on the IE and if there was a bunch of ideas which all appeared together it would simply flood me at that point in time instead of allowing me to go at my own pace. I would agree that the problem is probably because people don't follow the exchange, but the solution to that might be to make it more accessible. For example, the IE has an RSS feed for ideas, just like Shaun asked for - http://forums.ni.com...id=labviewideas The problem is that if you don't look for it, you don't know it's there. The site doesn't seem to make it accessible enough. Ideally, it should provide people with several ways of getting alerts to either ideas or comments. In any case, I think that people have to make a conscious choice to follow the exchange or they will have to rely as filters such as this thread to point them to specific ideas.

Ideally you wouldn't inherit from anything with an Initialize method. You would create an abstract parent class, move all existing methods and data up to that class (except for the Initialize), and your new class would be a sibling class, and thus able to have its own initialize. This is ideal because it maximizes flexibility for future development since each actual concrete class can evolve independently. Sometimes it isn't possible to make this mutation (especially if you need the LV auto-mutation of flattened strings to work for values saved in files or because you don't own the parent class), but if you can, that's probably the best route. When you can't do that, have a protected InitCore.vi that takes a dyn disp input and a public "Init X.vi" where X is the name of the class that does not have the class input. The descendant class would create its own "Init Y.vi", and it would call InitCore.vi to get the parent segment initialized.