National Instruments NI-488.2 - Manual (Page 113)

Appendix C Error Codes and Solutions
© National Instruments Corporation C-9 NI-488.2 User Manual
Solutions
Check to see if other devices not used by your application are asserting
SRQ. Disconnect them from the GPIB if necessary.
ETAB (20)
ETAB occurs only during the FindLstn and FindRQS functions. ETAB
indicates that there was some problem with a table used by these functions:
• In the case of FindLstn , ETAB means that the given table did not
have enough room to hold all the addresses of the Listeners found.
• In the case of FindRQS , ETAB means that none of the devices in the
given table were requesting service.
Solutions
In the case of FindLstn , increase the size of result arrays. In the case of
FindRQS , check to see if other devices not used by your application are
asserting SRQ. Disconnect them from the GPIB if necessary.
ELCK (21)
ELCK indicates that the requested operation could not be performed
because of an existing lock by another process accessing the same interface.
ELCK is also returned when a process attempts to unlock an interface for
which it currently has no lock.
Solutions
Call
iblck
to lock the interface. If
iblck
continues to return ELCK,
lengthen the
LockWaitTime
and wait for the other process to relinquish its
interface lock.
Ensure that you have successfully locked the interface prior to unlocking it.
EARM (22)
EARM indicates that ibnotify ’s asynchronous event notification
mechanism failed to rearm itself. This generally occurs when an ibnotify
Callback has attempted to rearm itself by returning an illegal value or
when a fatal driver error (EDVR) has occurred.