VEE Pro: Why can't I talk to an instrument at GPIB address 21?

VEE Pro Revisions: All

When you set an instrument to GPIB bus address 21 when using an Keysight GPIB card, you may have problems talking to the instrument.

The reason is that each device on the GPIB has to have a unique address, including the computer's GPIB card. Keysight GPIB cards default to using address 21 for themselves. The situation is not unique to VEE: any software using this hardware will encounter it. It's not unique to Keysight: any other manufacturer's GPIB needs to have an address for itself, though it may not be 21.

With some GPIB cards, the address may be changeable, with others it may not. The simplest solution is usually to avoid using 21 or other reserved addresses for an instrument address.

Other vendors of GPIB cards may have their own default settings, so you should read the manufacturer's literature before deciding on bus addresses.

Last Updated: 21September, 2004