Error reports converting a vi from LV8 to LV7.1

[Kousy]

Neatly working VI in LV8.0 for some reason I am converting it into earlier version of LV7.1. When I opened from LV7.1, I got the error message (report attached).

 

Hope somebody help me out to avoid coding from scratch.

 

Kousy

   

[Dennis_Knutson]

There is no attachment. If you click the preview button, the attachment is lost.

[Kousy]

Sorry.. Here is the attachment..

Kousy

[Dennis_Knutson]

Could you attach the 8.0 VI that you are trying to convert? It would seem that one of the VI's has no block diagram. If you saved a VI without a block diagram, you cannot save as a previous version and you can't load it in a newer version either.

[Kousy]

NO Blk diag_LV8.vi - this has no block diagram but i could not find any problem saving it into earlier version 7.1

Perf Print Report.vi - this is the vi i have not able to save it into 7.1 version. Even I have tried removing all the graphs I have used + printing options etc. still it is throwing out the same error msg.

Kousy

[MogaRaghu]

Whenever I try to convert large VIs done in LV 8.0 backward to LV 7.1, I end up with a huge list of VIs that are in VI.lib that could not be converted.

Is there any way to overcome this particular issue so that I can avoid redoing the whole VI in 7.1 ? The sample error list is attached .

Thanks

[Dennis_Knutson]

Kousy,

There are many subVIs missing from your perf print VI. Can you attach those?

Raghunathan,

VIs in vi.lib are not supposed to be converted. If you are using vi.lib functions in 8.x and they don't exist in 7.1, then you can't do the conversion. If the vi.lib functions do exist in 7.1, then just open the converted VI and ignore the warnings.

[MogaRaghu]

Dennis,

thanks for the clarification. And I guessed as much.

That said I really feel that this menu option to "Save for previous version" is pretty much useless. Maybe its fine for simple VIs with a few functions in them. Other than this I cannot imagine any practical use, as in any case large VIs are built using numerous functions from the vi.lib.

Looks like I need to recreate my existing LV8.0 vi right from scratch to LV7.1.

Raghunathan

[Dennis_Knutson]

I don't see much of a difference saving small VIs or large projects. Nor do I see any reason to re-create everything from scratch. You will get a top level VI when you do a save as and when you open it, it will load equivalent functions from the older vi.lib. You would have to try to re-create functions that only exist in 8.x. If you need to support both 7.x and 8.x, then you really need to be developing in 7.x. Newer versions always have features that do not exist in older versions and seldom do newer version remove anything that was in an older version.

[MogaRaghu]

Yeah I do understand the process of backward migration and also realize the unavoidable pit falls.

But in my case after the conversion is complete, and I try to open it in LV7.1, I simply get a dialog box with a" LabView Load error 24" and it says rather bluntly that the VI is broken and there is no block diagram !

Anyway I have not given up and am trying the converison in a logical fashion by removing some obvious functions that are not there in LV7.1. Shall revert if I get lucky.