ActiveX controls with TLA logic analyzer

[drew1005]

I'm trying to use ActiveX to control a Tektronix logic analyzer through TPI. However, I'm unable to access anything lower than the Application level. The help files on TPI say that the GetSystem Method returns the reference number for the System Class. However, when I try to convert this ref num and use it to open the System Class, I get an error that the "Class is not Registered". Has anyone gone down this path before or know how to get past this problem? I'm not sure I'm even wiring it up right.

Thanks

[KileenC]

Hi Drew,

It could be that you need to first register the type libraries and ActiveX controls/servers for your logic analyzer. There is a useful KnowledgeBase discussing this procedure:
KB 1HBAMMSR. How Do I Manually Register Type Libraries, ActiveX Controls, and ActiveX Servers?

Kileen C.
Applications Engineer
National Instruments

[drew1005]

I tried registering the type library, but that didn't help. I have tried un-registering it and re-registering it with no success. When I un-register the type library I can't even access the top level. However when I re-register it I can only access the top level.

It seems to me that there's a problem converting the variant which is returned from the GetSystem Method to a Automation Refnum which can be used in the Automation Open block for the System Class. Do you have an example of how to do this?

[KileenC]

Hi Drew,

Did you try using the Variant to Data.vi and wiring a Automation Refnum constant into the type input? I've attached a screenshot to this post.

Kileen C.

[drew1005]

I figured out the problem. I was doing as you describe, however I was wiring the output of the "variant to data" into an "automation open". When I removed the "automation open" and wired directly to an "invoke node", it worked as desired. Thanks for your help.