HP AHA-8940 Configuration And User's Manual page 26

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interface name
interface number
Figure 2-11. The HP I_O Libraries I_O Config Utility.
The HP E8491A uses the SICL interface name 'vxi' and the VISA
interface name 'VXI' (Figure 2-12). The VISA interface number is
assigned by 'I_O Config' and is unique to each E8491A. The interface
name and number identify each mainframe in multi-frame VXI
systems, and are also used in addressing each instrument in the
mainframe. The unique interface number allows instruments with the
same logical addresses to be installed in different mainframes, but in
the same system.
26 Interface Installation and Configuration Chapter 2