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National Instruments GPIB-PC User Manual

Page 42

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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