Chapter 8 wibconf-Windows Interface Bus Configuration Utility
© National Instruments Corp. 8-7 NI-488.2 User Manual for Windows
Board and Device Configuration Options
To view detailed information about each characteristic, position the cursor in the field for
that characteristic. For information on characteristics specific to a particular driver,
check the getting started manual that came with your interface board. The following
paragraphs describe the options available in wibconf for the NI-488.2 software for
Windows.

Primary GPIB Address

All devices and boards must be assigned a unique primary address in the range hex 00 to
hex 1E (0 to 30 decimal). The default primary address of all GPIB boards is 0.
The GPIB primary address of any device is set within the device, either with hardware
switches or a by software program. The address set within the device must correspond to
the address in the memory-resident driver. In the NI-488.2 driver for Windows, the
default primary addresses of dev1 through dev16, and dev17 through dev32 , are 1
through 16, respectively. Refer to the device documentation for instructions about setting
the device address. GPIB boards do not have hardware switches to select the GPIB
address.
The primary GPIB address is used to compute the talk and listen addresses of devices and
boards. The NI-488.2 driver automatically forms a listen address by adding hex 20 to the
primary address and a talk address by adding hex 40 to the primary address. For
example, a primary address of hex 10 has a listen address of hex 30 and a talk address of
hex 50.

Secondary GPIB Address

Any device or board using extended addressing must be assigned a secondary address in
the range hex 60 to hex 7E (96 to 126 decimal), or you can select NONE to disable
secondary addressing.
As with primary addressing, the secondary GPIB address of a device is set within that
device, either with hardware switches or by a software program. The address set within
the device must correspond to the address in the memory-resident driver. Refer to the
device documentation for instructions about secondary addressing. The default setting
for this characteristic is NONE for all boards and devices.

Timeout Setting

The timeout value is the approximate length of time that GPIB functions wait for data to
be transferred or commands to be sent. It is also the length of time that the ibwait
function waits for an event before returning, if the TIMO bit is set in the event mask. For
example, if the SRQI bit and TIMO bit in the event mask are passed to the ibwait
function and no SRQ is detected, then the function times out after the timeout period has
elapsed. The default option for this characteristic is 10 s.