Section Two
Installation and Configuration
©National Instruments Corp.
2-17
GPIB-PC User Manual
Situations which are checked are as follows:
•
GPIB addressing conflict between a device and its access
board;
•
GPIB boards not present in the host machine at the specified
address; and
•
Timeouts disabled on a device or board.
If any of these situations is encountered, you will be notified and given
the option of re-entering or exiting
IBCONF
. To disable auto-checking,
call
IBCONF -E
.
After exiting, the system MUST be rebooted for the new values to take
effect.
Some functions may be called during the execution of an application
program to change some of the configured values temporarily. These
functions are shown in Table 2.2.
Table 2.2 - Functions that Alter Default Characteristics
Characteristic
Dynamically Changed by
Primary GPIB address
IBPAD
Secondary GPIB address
IBSAD
End-of-string (EOS) byte
IBEOS
7- or 8- bit compare on EOS
IBEOS
Set EOI with EOS on Write
IBEOS
Terminate a Read on EOS
IBEOS
Set EOI w/last byte of Write
IBEOT
Change board assignment
IBBNA
Enable or disable DMA
IBDMA
Change or disable time limit
IBTMO
Request/release system control
IBRSC