Daqmx Lock up USB cdaq 9178

[RichC]

I am using CDAQ  9178 its a usb device and I have configured task in MAX The issue is i get lock up on the Cdaq quiet frequently requiring PC reboot looking at the attached image the called task just sits there and does progress pass the start daqmx function I have only put the diagram in trace to illustrate where the issue is The call to this sub vi is from further up the hierarchy 

This particular set of test sets an output on the cdaq which stimulates a pulse response the pulse width is measured with this VI call to an input module on the Cdaq

to try over come the problem I start he timer first wait 1.5 seconds then set the output

the input has a 10second time out

so there should be plenty time to run the function

The function works but when it locks up it just sits there indefinatley

Any ideas on the issue  and what the soltion is

 

[chidambar]

Hi Rich C

Just go through all the exampal programs of DAQmax, you will find these exampal in labview help find exampal in that you vave to choose Input and Output / DAQmax exampals.

I think you have made some mistake in programming, first use create task befor starting the task.

Hope it will help you.

[RichC]

I am familiar with creating task with in daqmx In this instance I have preconfigured the tasks I wish carry out in the MAX environment The jpg is just a snippet of the overall program It appears to be more related to the cDAQ but I no prove of this Maybe to do with usb It appears to be if multiple tasks are started too close together   In the case here I am starting the counter / timer input then activating the stimulus from output device  With out delaying these in my labview code the lock up occurs  Unplugging the usb when it happens does not help After the usb device is not recognized The only solution is to turn off the pc  If this is the case is there a work around Is this a known problem? Is it related to the driver?  Hopefully NI technical can advise too

[Jan_Nielsen]

Hej, I have a similar problem also on a cDAQ 9178, when I do Period Measurement. The VI locks, and if I try to stop LabVIEW, it gives the message "Resetting VI: Pulse Stand-Alone.vi" (the name of my VI). I also have to turn off power to the PC. Is this the same you experience ?

The "funny" thing is, the code works OK on the old cDAQ 9178-chassis.

BR, Jan

[Jan_Nielsen]

I forgot a question - is this happening the first time you run the VI, or later ? In my case, the error never occurs when I start the VI for the first time, but if I start and stop it several times, the error occurs after 2-8 start and stops. A workaround (but a quite unsatisfying one) actually is to close LabVIEW completely when I close the VI. Then the error does not show up.

[RichC]

Jan  Thanks for your response Simply the failure mode you describe is identical to the issue I am seeing with the resetting VI message and nothing else happensLike you too it does not happen on first call either but will happen on the Nth call I am using counters to both generate and measure pulse width As a consequence I do not want to call the task just once in my test suite programs  You right too shutting down labview is not really an answer!! Just to ask what versions of software are you using?

I have Daqmx 9.02 and MAX 4.6.1.fo and using labview 2009 v9

 The Cdaq 9178 is a new one we only purchased it couple months back and first time here we used them  It’s populated with 5 modules at moment (2 x NI 9422 (digital in) 1x NI 9476 (32 lines digital out) 1x NI 9481 (4 channel relay card) and 1 x NI 9221 analogue input card) Jan have you had any technical help from NI yet on this? Interesting that you say previous version of the hardware did not exhibit the same issue I don’t believe the issue is just on the counters but so far haven’t proved it  Not sure next step but very useful to know I am not only one experiencing the issue   

[Jan_Nielsen]

Hej, regarding SW version, I'm currently running on the newest: 2009 SP1, with DAQmx 9.10. But I have tried it on 8.2 and 2009 also with slightly older DAQmx versions, this makes no difference.

I am in contact with NI Denmark, but no answer yet. Actually, yesterday evening I tried two things, which made a change - the error before came after 2-8 restarts (never more than 8), but now I only saw it after 60 restarts. My two changes were:

- NOT wiring the error cluster to the Clear Task vi. I have a suspicion, the Clear Task vi is not working correct on 9178 when there is an error wired to it. I must say I am not sure about this, but maybe it's worth a try?

- adding DAQmx Reset Device at the end of the loop. I do this for first the modules, then the chassis.

If you have time to try these changes, it would be very interesting to hear your results.