I am using a GPIB-ENET/100 in a test rack with MAX software version 3.0.2. On device in the rack will shutdown the MAX software when performing the Scan for Instruments. Any idea why this might be happening?

[Marsha]

I am using a GPIB-ENET/100 in a test rack with MAX software version 3.0.2. On device in the rack will shutdown the MAX software when performing the Scan for Instruments. Any idea why this might be happening?

[ScottieB]

There is a known issue with NI-488.2 v2.2 and instruments that return a rather long "*IDN?" response. This might be your problem. If the instrument returns more than 99 bytes, MAX will behave in this way. The workaround is to not use "Scan For Instruments" in MAX. The "Scan for Instruments" functionality is designed to help you find your instruments on the bus, but it is not required before communicating with them in LabVIEW (or other programming languages). As long as you know what primary address your instrument is using, you can simply use that when trying to communicate with that instrument.

This issue will be fixed in a future version of NI-488.2.

Thanks,
Scott B.
GPIB Software
National Instruments

[Marsha]

Does NI-488 v1.7 issue a *IDN? command during "Scan for Instruments" ?

[ScottieB]

Yes, it does, but I am not sure if this issue is present in v1.7 or not. You do not need to use "Scan for Instruments" if you already know your primary address, however.

Scott