Chapter 3
Developing Your Application
VXI-1394 Interface for Windows NT/98
3-4
www.ni.com
•
Receive data from your GPIB device
•
Troubleshoot problems with your application
Advanced Communication
For advanced interactive communication with GPIB instruments, use the
Interactive Control utility, as follows:
1.
Select Start»Programs»National Instruments NI-488.2»Explore
GPIB to start Measurement & Automation Explorer.
2.
Expand the Devices and Interfaces directory by clicking on the + next
to the folder.
3.
Right-click on your GPIB interface and select Interactive Control
from the drop-down menu that appears.
4.
At the command prompt, type NI-488.2 API calls to communicate
interactively with the your instrument. For example, you might use
ibdev
,
ibclr
,
ibwrt
,
ibrd
, and
ibonl
.
To view the online help for Interactive Control, type
help
at the Interactive
Control command prompt.
Programming with VXI and GPIB
National Instruments provides three different programming interfaces for
accessing your instruments: NI-VISA, NI-VXI, and NI-488.2. NI-VISA is
the National Instruments implementation of the VISA API as defined by
the VXIplug&play standard. It is very useful in situations where you have
different types of instruments in your system—such as VXI, VME, GPIB,
and serial devices—because the NI-VISA functions have the same
interface.
NI-VXI is the National Instruments proprietary interface for programming
VXI/VME instruments. Both NI-VXI and NI-VISA grant you register-level
access of VXI instruments as well as messaging capability to
message-based devices. With either interface you can service asynchronous
events, such as triggers and signals, and also assert them.
NI-488.2 is the National Instruments industry-standard implementation of
the ANSI/IEEE Standards 488.1-1987 and 488.2-1992. The original GPIB
(General Purpose Interface Bus) specification, known as ANSI/IEEE
Standard 488.1-1987, describes a standard interface for communication
between instruments and controllers from various vendors. It contains
information about electrical, mechanical, and functional specifications.
