VISA GPIB - setting SRQ

[stevem181]

Hi folks,

WinXp

LabView 8.5

PCI-GPIB

Note: I am creating a GPIB instrument using the VISA vis, I'm not trying to

communicate with an instrument.

I have a working prototype that responds to GPIB writes and returns data.

Now I need to add the ability to generate an SRQ so the system controller (CIC)

can be set to wait for an SRQ before querying for a response.

I can't seem to find a way to set the SRQ line using the VISA vis.

Any help would be appreciated,

steve

P.S.

I have checked all of the online VISA documents, Developer Zone examples, and all forum messages about VISA and GPIB

[Chris G in AE]

Hey Steve,

Check out this KB on Setting Up an SRQ Interrupt Service Routine with the GPIB Driver. Let me know if you've already read that or if it's able to help you out. 

[smercurio_fc]

I don't think the user is trying to set up an SRQ service routine, and besides he's asking about how to use the VISA functions, not the raw GPIB driver, which is what that KB article addresses. A search on the forums turned up this answer: http://forums.ni.com/ni/board/message?board.id=170&message.id=303215

[stevem181]

Thanks for the replies. Apparently there is no way to set the SRQ using VISA.

My attempts to use the GPIB Misc vi to set the SRQ line (with command string "rsv @") have not been very successful.

Sometimes the SRQ is set and sometimes it is not. The output string and status lines coming from the

GPIB Misc function never change in either case :(.

I shouldn't have to do this, but next I will try to use the iblines dll call to check the SRQ line and repeat the GPIB Misc call until

it "takes".

Which makes me think that I might as well look for a dll call that will set the SRQ line directly.

It appears that very few people use LabView to create an instrument interface so the toolset is very limited for this purpose.

steve

[smercurio_fc]

Well, that doesn't mean the toolset is very limited. The same could be said about C# or VB if it doesn't happen to have the functions to do what you want. LabVIEW allows you to call DLLs just like most other languages, so I would say the toolset isn't limited. You are essentially trying to simulate an instrument with software. You will need to do some low-level operations, and in any language you use this is not trivial. Ultimately I believe you will need to directly call the GPIB driver, and it doesn't matter whether you do this in LabVIEW or C - the effect should be the same.