Errors During Serial Poll - HP 9000 Series 300 Tutorials Manual

Errors During Serial Poll
If any of the following error conditions are encountered during a call to
hpib_spoll,
the subroutine returns -1:
• Addressed device did not respond to serial poll before the timeout limit
defined by
io_timeout_ctl
was exceeded.
• Computer interface is not current Active Controller.
• Entity identifier eid does not refer to an
HP-IB
raw interface file.
• Entity identifier eid does not refer to an open file.
• Address is outside the range [0,30].
• The interface associated with this eid is locked by another process and
D_NDELAY
is set for this eid.
To determine which of these conditions caused the error, your program should
check for the following values of errno:
errno Value
EBADF
ENOTTY
EIO
Error Condition
eid does not refer to an open file.
eid
does not refer to a raw interface file.
The interface was not the Active Controller. (EACCES on Series 800)
ETIMEDOUT A timeout occurred. (EIO on Series 300)
EACCES
EINVAL
The interface associated with this eid was locked by another process
and
O_NDELAY
was set for this eid.
Invalid bus address.
3-48 Controlling the HP-IB Interface