National Instruments NI-488.2 ユーザーズマニュアル

© National Instruments Corporation

NI-488.2 has 

libgpibapi.so

—a dynamic library you can use from your 

C/C++ applications. Refer to the 

 section for more details on how to develop your 

application.

The NI-488.2 API has two subsets of calls to meet your application needs. 
Both of these sets, the traditional calls and the multi-device calls, are 
compatible across computer platforms and operating systems, so you can 
port programs to other platforms with little or no source code modification. 
For most applications, the traditional NI-488.2 calls are sufficient. If you 
have a complex configuration with one or more interfaces and multiple 
devices, use the multi-device NI-488.2 calls. Whichever option you 
choose, bus management operations necessary for device communication 
are performed automatically.

The following sections describe some differences between the traditional 
NI-488.2 calls and the multi-device NI-488.2 calls.

If your system has only one device attached to each interface, the traditional 
NI-488.2 calls are probably sufficient for your programming needs. 
A typical NI-488.2 application with a single device has three phases:

•

Initialization: use 

ibdev

 to get a handle and use 

ibclr

 to clear the 

device.

•

Device Communication: use 

ibwrt

, 

ibrd

, 

ibtrg

, 

ibrsp

, and 

ibwait

 to communicate with the device.

•

Cleanup: use 

ibonl

 to put the handle offline.

Refer to the sample applications that are installed with the NI-488.2 
software to see detailed examples for different GPIB device types.

For NI-488.2 applications that need to control the GPIB in non-typical 
ways—for example, to communicate with non-compliant GPIB 
devices—there is a set of low-level functions that perform rudimentary 
GPIB functions. If you use these functions, you need to understand GPIB 
management details such as how to address talkers and listeners. Refer to 
Appendix A, 

, for some details on GPIB management.