NXT Case Structure with Integer ranges (Archived)

[David_Fort]

Update: This discussion applies to Issues from the 2010 FTC season and is no longer relevant for current FTC competition software. Case sturctures have been rewritten for the NXT in LabVIEW for LEGO MINDSTORMS, if you have case sturture issues please create a new post.

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On NXT, Case Structure using integers is OK, but using integer ranges, like 7..14 yields an error like "can't run vi"  or something like that.

(sorry, didn't write down the number or exact text).

The message and help are mostly about not being able to find the vi and suggestions for how to help LabView find it.

Through exhaustive process of elimination, we found the cause to be use of ranges in the case selector.

This page: http://zone.ni.com/reference/en-XX/help/372962A-01/lvnxt/makingadecision/

says ranges can be used in "direct mode", but not "remote mode"

What does "remote mode" mean?

Thanks.

[Philbot]

"Direct Mode" refers to when you run the VI "Targeted to PC"... vs "Targeted to NXT"

In Direct Mode, the program is acyually running on the PC, and it's sending low level commands to the NXT to control the perhipherals.

So in this mode ALL of labview's capabilities are available.

In "Remote Mode" the program is compiled and downloaded to the NXT, so only SOME of LabVIEW's functions are available.

One such missing function is the "full featured" case structure.  You need to stick to basic true false, or simple integer cases.

Also missing are multi-frame sequence structures, For loops and multiple output array indexing...

In the "LabVIEW for NXT" manual there is section which lists the un-supported functions.  Don't recall the exact name, but that's the magic bullet for determining what is/not supported.

Phil.

[David_Fort]

Thanks.  That document (or at least the version of it that I found) says Floating Point isn't supported on the NXT.

Is that really true?

[Philbot]

Hi.

No, that's not true.  The NXT is fine with floating point .

I reported that doc error about a year ago.  Looks like no-one's fixed it.