What determines which inputs you can select from when you're creating a VISA Resource Name Constant?

[Phredrick Dobbs]

Hey, I'm trying to write a labview driver an instrument. I have another instrument which came with labview drivers, and I had hoped that by looking at how they did it, I could write my own for this piece of equipment.

However, the problem is they use the old visa open method. That is, they input a string, "GPIB::6", and it outputs a visa session.

The new Visa open requires that you have an input resource name, and the constants only let me pick from "COM1" and "LPT1", but the GPIB interface card in this computer is in a PCMCIA slot.

What determines what choices you get when you select the value of the constant?

Thanks,
-Dobbs

[Shan Pin Koh]

If you created a VISA Resource Name control, right click on the control and select "Allow Undefined Names".

I haven't programmed directly using VISA on LabVIEW 6 but it apppears that if you select from the drop-down menu, it shows the devices that is defined in MAX. Thus, you should be able to select your GPIB resource name if it has been properly installed.

Nevertheless, it still allows you to override the control by selecting "Allow Undefined Names".

I hope that helps.

Shan Pin Koh

[Shan Pin Koh]

FYI, you can also right click and select Allow Undefined Names" for VISA Resource Name constant.

Sorry but I misread your title earlier...

Shan Pin Koh

[Brian_Vibert]

Right-click on the constant and select "Allow Undefined Names". Once this is selected you may type in any thing you want. If you have your devices configured in MAX you can use the alias names that can be set for each device. If you don't have your devices configured thru MAX you can use the standard naming convention you mentioned by typing it in the constant.

Hope this helps!

Brian

[Rob Cole]

The nice thing about the standard naming convention is that you can use just about any GPIB card in the computer. HP's VISA drivers do not co-exist with NI's MAX very well (from experience), but using the standard naming convention will allow the program and instrument to be used on just about any machine.