GPIB/GPIB-488.2 Library Chapter 4
LabWindows/CVI Standard Libraries 4-10 © National Instruments Corporation
Global Variables for the GPIB Library
The following global variables are used by the GPIB Library and the GPIB-488.2 Library:
• Status Word (ibsta)
• Error (ibcnt, ibcntl)
These variables are updated after each NI-488 or NI-488.2 routine to reflect the status of the
device or board just accessed. Refer to your NI-488.2 user manual for detailed information on
the GPIB global variables.
Different Levels of Functionality Depending on Platform and GPIB Board
In general, the GPIB library is same for all platforms and GPIB boards. There are, however,
some exceptions, most notably relating to SRQ notification, support for multithreading, and
limitations on transfer size. These particular issues are discussed later in this chapter. This
section explains the various categories of GPIB support.
Windows 95
There are two kinds of GPIB support for Windows 95. The “native 32-bit” driver and the
“compatibility” driver. You can see which one you have installed on your system by running the
GPIB Information program in your GPIB Software group and noting the name of the driver.
Driver Name Description
NI-488.2M Native 32-bit driver.
NI-488.2 Compatibility driver.
Native 32-Bit Driver
The native 32-bit driver is a 32-bit device driver written specifically for Windows 95. It is
supported on the following boards.
• AT-GPIB/TNT
• AT-GPIB/TNT+
• AT-GPIB/TNT (PnP)
• PCI-GPIB
• PCMCIA-GPIB
• PCMCIA-GPIB+