intermittent error message using DAQmx in same programas VISA

[Tim_W]

I have a loop VI which drives a motor with VISA serial then reads position with DAQmx analog voltage.  After about 80 iterations (80,78,79), an error message, either -88710 0r -201003 DAQmxCreate Channel, halts the program.  This is my first DAQmx VI.  Any ideas?  VI's attached.  Thanks in advance!

[RyanPoPo]

Hey Tim,

When this error occurs, can you still communicate with your DAQ in MAX using test panels? If the code that you provided is indeed run in a loop, then it may be beneficial to modify your code so that you create the DAQmx channel once before entering the loop, instead of constantly creating and clearing the Task in the SubVI. You would basically just have the DAQmx Create Virtual Channel outside of your loop, pass the reference it creates into the loop and into your Stacked Sequence Structure, into the SubVI as in input, and then pass the the reference back out to be closed by the Clear Task VI outside of the loop once it has finished executing.

Regards,

Ryan

[Tim_W]

After following a series of rabbit trails not leading to the solution, I wrote code to try to clear the error and continue the program.  This sort of worked.  The error was cleared, but the program still halted....until I 'woke' the computer up next time I checked on the program.  Then the program would continue!  So I suspected that it was something to do with the computer screen saver or power management settings.  Changing the power management settings to 'never' fixed the problem-no more error on the VISA read!  Strange but true!