iberror EDVR(0)

[reymonf]

using NI spy to troubleshoot I have the following: iberror EDVR(0) after UD1023 and I receive a visual basic 6 error: error 9 subscript out of range.   In myapplication i talk with two agilent dmm and a HP 7001 switch sytem .  I notice that UD increments as i talk to the three instruments.  any advice is wellcome.

thanks,

reymonf

[JohnM 64]

Hi raymonf,

Is your UD "incrementing" only as you switch between the three devices?  Or is it incrementing each time you communicate with a device?  Perhaps you could post the spy log in order for us to understand this problem better.  Each device should only have a single board descriptor that should not change as the program executes.

john m
Applications Engineer

[reymonf]

Hi:  Its increments UD only when I switch between device.  If I only use one device it not increments.

attached please see Ni spy log.   Note;  I change the extension

[NI-488.2 master]

It appears that the problem is that the application is continuously opening NI-488.2 device handles, without ever closing any of them.  Instead of calling ibdev in a loop, just call it once for the application and save the ud that comes back.  That, or when the application is done using the handle for a moment, call ibonl(ud, 0) to close the device handle.  The NI-488.2 driver has a limit of 1024 open device handles.

Craig A.
National Instruments Engineer

[reymonf]

problem solved !!!  use ibonl 0 after each call to the devices.

Thanks for your help. NI has tremendous support.

reymonf

[reymonf]

problem solved !!!  use ilonl 0 after each call to the devices.

Thanks for your help. NI has tremendous support.

reymonf