Addressing A Session - Agilent Technologies ESA-E Series Programmer's Manual

Programming Example s
C Programming Examples using VTL
The above function first opens a session with the default resourc e
manager. The session returned from the resource manager and a devic e
address is then used to open a session with the GPIB device at addres s
22. That session will now be identified as dmm when using other VTL
functions . The session returned from the resource manager is then use d
again with another device address to open a session with the GPIB/VXI
device at primary address 9 and VXI logical address 24 . That session
will now be identified as scanner when using other VTL functions . Se e
the following section for information on addressing particular devices .
Addressing a Sessio n
As seen in the previous section, the rsrcName parameter in the viOpen
function is used to identify a specific device . This parameter is made u p
of the VTL interface name and the device address . The interface name
is determined when you run the VTL Configuration Utility . This name
is usually the interface type followed by a number. The following table
illustrates the format of the rsrcName for the different interface types :
Interface Syntax
VXI
VXI [board] : :VXI logical address[: :INSTR]
GPIB/VXI GPIB-VXI [board] : :VXJ logical address[ : :INSTR]
GPIB GPIB [board] : :primary address[ : :secondary address][ : :INSTR]
The following describes the parameters used above :
board
This optional parameter is used if you have more tha n
one interface of the same type . The default value fo r
board is O .
VXI logical
address This is the logical address of the VXI instrument .
primary
address This is the primary address of the GPIB device .
secondary
address This optional parameter is the secondary address of the
GPIB device . If no secondary address is specified, non e
is assumed .
INSTR This is an optional parameter that indicates that you
are communicating with a resource that is of typ e
INSTR, meaning instrument.
NOTE
If you want to be compatible with future releases of VTL and VISA, yo u
must include the INSTR parameter in the syntax .
The following are examples of valid symbolic names :
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