Switching Between LabVIEW 7.1 RT and LabVIEW 8.0 RT Repeatedly

[kehander]

I've been writing some programs that take advantage of the new features in LabVIEW 8 that I can run on my PXI RT target. However, I still have a lot of 7.1 programs that I would prefer to continue running under LabVIEW 7.1 for now.

This presents a problem, since it seems to me that LabVIEW 7.1 cannot connect to a target running LabVIEW RT 8. (I'm not supposed to be able to do that, am I?) Thus, is there some fast and easy way to switch between LabVIEW RT 7.1 and LabVIEW RT 8.0 on an RT target?

I've found that using MAX to uninstall all the software on the PXI and then re-installing it tends to result in an unstable installation in some cases with various kinds of stange behaviors. Lately, to switch versions, I just reboot the PXI in Windows XP mode, remove the NI-RT directory and the four files in the root directory (hdmon.bin, ni-rt.ini, persist.pal and phexec.exe), and reinstall from scratch, but this is a little time-consuming. Removing the files and directories from one version and putting them back after using the other version also results in instability and strange behavior.

Has someone else done something like this already? Is there something else I can try?

[Greg G.]

I've done the following in the past to solve this issue:

1) Install LVRT version X on the target.  Reboot into DOS/windows and rename the c:\ni-rt folder to c:\ni-rt-X.  Copy ph_exec.exe, ni-rt.ini, etc into this new folder. 

2) Install LVRT version Y on the target.  Reboot into DOS/windows and rename c:\ni-rt to c:\ni-rt-Y and copy root files into it.

3) Create a bootable DOS floppy that has batch files "setX" and "setY" which simply copy either c:\ni-rt-X or c:\ni-rt-Y to c:\ni-rt (and copies the root files back to the root).  Then you don't have to keep reinstalling through max and you can somewhat quickly switch between versions.

greg

[kehander]

That's a very nice idea, but like I said, I've tried something like that already, and stange errors start happening when I switch between the two versions. I suspect the MAX installation also writes to the boot sector or something else that isn't immediately obvious (subsequently resulting in compatibility issues of some sort after "manually switching"), but that's just speculation.

Do you not find anything unusual happening when you switch between versions like that?

[kehander]

No other clues?

I would have thought there would be more people trying to do this sort of thing.

[NathanT]

kehander,
      Are you not able to just transfer your 7.1 code into 8.0?

[kehander]

I suppose I could, but I am concerned that the long start-up time of LV8 and the need to run the program through a project may cause inconvenience for the end users.  (Or maybe these little problems will be cleared up in 8.2.)

[NathanT]

kehander,
       LabVIEW 8.2 has a much faster start-up time.  Using the project might take a little getting used to for your end users, but it is the direction that LabVIEW is moving in, so if you can get your end users comfortable with it now, it will save you the hassle of having to switch between 7.1 and 8.0.

Thanks,

Nathan

[stranger]

This is will not work if you have upgraded already to labview 8.x or have it already as labview
RT will in general not degrade files to previous version if it's older...
I have tried degrading my installation and it appears to work, but it alway keeps the latest version.
What is needed is some sort of dual boot.
This could be quite easy if you had partition tools as found on the PC. since LV RT uses ide & Fat32,
you can simply uplug the harddrive and plug it into a regular PC and partition it into two partitions etc
and the set one for boot partition. Put it back into the system and install labview 7.1 and then change
to the other partition and then install labview 8.x.
All you need now is a small program to to change the active partition installed on all the partitions.
This perhaps is far too complex perhaps but it's the only for now to enure you're really running 7.1
0r 8.1 Offcourse NI could release a tool like this easily.

Walters

[JR_A.]

You could use the LabVIEW Real-Time System Replication Tools to store images of the target with the different versions. If you still have issues with strange things happening in MAX after imaging the target I'd recommend letting NI's support team know.

-JR A.