System crash when DAQmx call to USB DAQ device is powered off

[Exijus]

My PC crashes when I attempt communication with a NI DAQPad 6015 USB device which is in the powered off state. I am attempting to add error handling to my LabView application to cover the above condition, however, instead of receiving a error message, my PC crashes. When the device is powered on, my LabView routine works properly. I created the vi using the DAQmx DAQ assistant for a simple analog read from the device. I want to add the potential error handling condition to cover the case in which a user may attempt to run the software without turning on the device. When I attempted to run my vi twice with the device powered off, my PC crashed both times. The 2nd time, during reboot, I discovered that MAX was corrupted and had to repair using the installation CD.

I am using LabView 7.1 with DAQ 7.4 on Windows 2000.

Is there a known fix or workaround to this issue? Or is there a way to detect the presence of the device first before trying a DAQ read?

Thanks,
Joel

[DimensionFinder]

Hi Joel:

I simply get an error message when I try to do what you are doing. It could be a problem with DAQ Assistant. What I would recommend doing is going to one of the example programs which you can find by openning a blank VI in LabVIEW and choosing Help>Find Examples from the menu.

If you can replicate this problem by running a simple program in LabVIEW then I will try to run the same program and see if I can see the behavior. The point is, we should try and run the same VI to see if the problem is isolated to your computer or if it is universal.

Also, what happened when you repaired MAX? Did this help?

[Tesla1977]

Almost the same thing here.

Here we use DIAdem to measure different global channels from a DAQPad6015MassTerm with a SCC-2345.
When switching the device off while DIAdem is acquiring samples, bsod. When starting and completing a measurement while device is on, everything works. Shutting off the device and restarting the measurement -> bsod.
STOP: 0x0000001E (0xC0000005, 0xB687026D, 0x00000000, 0x00000000)KMODE_EXCEPTION_NOT_HANDLED
Address B687026D base at B6867000, DateStamp 42299B1E - nimsdrk.dll

[Exijus]

Thanks very much for both your responses. I tried it again, but as you suggested, I used one of the example vi's. I chose the following:
Acq&GraphVoltage-IntClk.vi found within: Hardware Input and Output >> DAQmx >> Analog Measurements >> Voltage

I first tested the example vi with my DAQPad-6015 powered on. The vi successfully ran without error. I then turned the DAQPAd power off and ran the vi again. My system immediately crashed leaving me with a blank screen (with streaky lines) and forcing me to reboot. After reboot, I discovered that I can no longer open any of the DAQmx examples that are compatible with the DAQPad-6015. All are corrupted. Curiously, MAX was not corrupted again. I will have to re-install all examples and possibly LabView itself.

Based on your feedback, I am guessing you will tell me that repeating the above on your system will simply produce an error message, as expected. It appears that I may have a fundamental incompatibility between my specific system hardware and DAQmx/LabView.

Regards,
Joel

[DimensionFinder]

Hi Joel:

Let me try that and get back to you.

[DimensionFinder]

Hi Joel:

My apologies for the last post. I had tried it with a 'simulated' device when I got that error. I tried it with a DAQPad 6016 today and saw the same results as you did. It did not give me any specific error but it just restarted my computer. It seems like the behavior when you turn off the device is rather erratic and varies. R&D here at NI is aware of the issue and will most likely fix it. However, there is no date as to when that will be done by.

I apologize for the inconvenience but as of now this is "expected behavior" until it is fixed by R&D.

[Exijus]

Thanks for your latest info and for taking the time to confirm this issue. I look forward to hearing about a permanent fix, hopefully, in the near future. In the meantime, I will apply the necessary instruction to my customer to never attempt running the software without first powering on the DAQPad.

Thanks,
Joel

[Jeremy_C]

I was unable to reproduce the crash with NI-DAQmx 7.5 (link below).  Instead I received -50002 from DAQmx Start Task.vi saying the specified device is not a valid device, which is an appropriate error.  I recommend upgrading to this version of NI-DAQmx.  If you still see the problem, be sure and reply back.

http://digital.ni.com/softlib.nsf/websearch/CF7ECCEA4C4CC7DE86257038004D88AE?opendocument&node=132060_US 

[Exijus]

Jeremy,

I installed DAQ 7.5 and re-tested with the same conditions.  I received an appropriate error message instead of a system crash.  The bug appears to be fixed now!

Thanks for the notifying me on the new DAQ release.

Regards,

Joel