National Instruments NI-488.2 NI-488.2 User Manual page 111

Appendix C Error Codes and Solutions
ELCK (21)
Solutions
EARM (22)
Solutions
EHDL (23)
NI-488.2 User Manual
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.
Call to lock the interface. If
iblck
lengthen the
LockWaitTime
interface lock.
Ensure that you have successfully locked the interface prior to unlocking it.
EARM indicates that
mechanism failed to rearm itself. This generally occurs when an
has attempted to rearm itself by returning an illegal value or
Callback
when a fatal driver error (EDVR) has occurred.
Ensure that the value being returned by your Callback function is a valid
mask value.
ibnotify
Return a zero value from your Callback function to unregister the
asynchronous event notification mechanism. Then call
re-enable notification.
EHDL results when an invalid handle is passed to a function call.
The following are some examples:
• A valid board handle is passed in as a handle parameter to a
device-level NI-488 function or a valid device handle is passed
in as a handle parameter to a board-level NI-488 function.
• An invalid board or device unit descriptor is passed as input to any
NI-488.2 function.
continues to return ELCK,
iblck
and wait for the other process to relinquish its
's asynchronous event notification
ibnotify
C-10
ibnotify
to
ibnotify
ni.com