Chapter 7
Using the NI-VXI/VISA Software
7-2
www.ni.com
Interactive Control of NI-VXI/VISA
The easiest way to learn how to communicate with your instruments is by
controlling them interactively. Use the VXI/VME interactive control utility
(
victext
) to write to and read from your instruments. This utility displays
the status of your VXI/VME transactions and informs you of any errors that
occur.
Refer to the online help for instructions on how to use
victext
and to learn
about the features of each.
Example Programs
The
NIVXI/examples
subdirectory contains various example programs
along with a makefile that show how to use various functions in the NI-VXI
software and how to develop application programs using these functions.
Make certain that the environment variable
NIVXIPATH
is set correctly as
described in Chapter 5,
NI-VXI/VISA Software Installation
. Also refer to
your software utilities reference manual for additional examples.
For NI-VISA programming examples, look in
VXIpnp/linux/NIvisa/Examples
.
Programming Considerations
The following paragraphs contain information for you to consider when
developing Linux applications that use the NI-VXI/VISA bus interface
software.
Multiple Applications Using the NI-VXI and VISA Libraries
Multiple-application support is another feature in the NI-VXI/VISA
libraries. You can have several applications that use the NI-VXI and/or
NI-VISA libraries running simultaneously. In addition, you can have
multiple instances of the same application running simultaneously.
The NI-VXI/VISA functions perform in the same manner whether you
have only one application or several applications (or several instances of a
single application) all using the NI-VXI/VISA libraries.
However, you do need to be careful in certain cases as described in the
following section.