Knob control locks up labview

[arvin_labrat]

I trying to make a VI that has a knob control that acts as a trim pot.  I've attached the VI I'm working on.  The problem I am running into is, on the second or third revolution of the knob labview lockup.  I have to use the task manager to end the labview task.  I watched the CPU as I was turning the knob, and the CPU went up to 35 % for the first revolution then lock up to 100%.

I was wondering if anyone else has seen this behavior before.

I am using LV 8.5 on Win XP

Thanks

[Dennis_Knutson]

I don't see any problems when running it in 8.6. the cpu usage goes up to around 5-6% as I rotate it as fast as I can and drops to 0 as soon as I stop.

[elset191]

I got my cpu up to about 80, but it never really locked up.  Just for a second a few times.

8.6 on XP on 5year old laptop

[arvin_labrat]

I started thinking about this problem last night and considered the event structure may be the issue.

So this morning I revised my vi and removed the event structure.  Same results.

I am using LV 8.5 on Win XP

[arvin_labrat]

Just for fun, I saved a copy of my Rev2 Vi back to LV 8.2 and got the same results.

If nobody else is having this problem I'll assume its my computer and bug my boss for a new top of the line computer.

Thanks again

[RavensFan]

What kind of PC are you using?  Processor cores, speed?

I tried running both your VI's on two different PC's in LV2009 and LV 8.5.1 and saw no problems.

One thing I would recommend is to swap the cases where you do your incrementing/decrementing.  I noticed that with both VI's, if you go to the clockwise/positive direction, your count decreases to negative revolutions.  If you go to the negative, or counter-clockwise direction, the count increases.  I think this logically should be the opposite way.

[Pablop]

I have a 5 year old HP work station, the CPU got up to 30%, but never higher. Looks like a good excuse to upgrade:)

[arvin_labrat]

Raven

I have a Toshiba Tecra M3

OS:             Win XP  SP3

Processor:   Intel Pentium M @ 1.6 GHz

Ram:           768 MB

Your right about the case structure, I was getting ready to fix that when my computer started locking up.

[altenbach]

I thought I recognize that code. 😮

Maybe you want to try to uncheck "lock front panel until event completes" in the event configuration. See if it makes a difference.

You can also delete the timeout case, it does nothing.

[arvin_labrat]

Altenbach

Thanks for the example.  I tried your suggestion with the same result.  The Rev 2 example I posted does not have an event structure and it produces the same result.

I'm probably going to do something else in my project but it would be nice to know what is causing LV to lock up so I won't do that anymore.

Thanks again