Configuring NI GPIB boards to work with MET/CAL

When using two National Instruments (NI) GPIB boards with MET/CAL, initial configuration is always required.  Even after the boards are installed and operational with their correct drivers, each board must be assigned a GPIB Interface ID using NI’s Measurement & Automation Explorer (NI MAX).  The NI MAX software will automatically assign the ID after installation, and typically remembers each board’s ID.  Some detachable form factors (USB, PCMCIA, ExpressCard, etc.) may not retain their original IDs if they are removed and re-attached.  Instructions for reviewing or changing Interface IDs can be found on the NI website.  Note that the instructions are different depending on NI-488.2 driver version.  Also, if you are running the Windows 7 operating system, you must right-click NI MAX and select “Run as administrator” in order to make changes to the configuration.

MET/CAL must also be configured to use both boards.  The GPIB reference standards are expected to be found on GPIB0, and the UUT on GPIB1.  In version 8, the number of boards and also the board type can be configured using either Run-Time or Editor:

Run-Time: Configure > IEEE-488 Boards Editor: Tools > Configure IEEE-488 Boards

If you are ever presented with error messages from MET/CAL, saying that none of the GPIB reference standards can be located on the bus, Interface ID assignment is a very likely culprit.  NI MAX’s automatic assignment seems to change more frequently when using two detachable GPIB boards.  It may be desirable to use two different form factors to enhance reliability, with only one of them being detachable (i.e. one PCI plus one USB).

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