Appendix B
Error Codes and Solutions
© National Instruments Corp.
B-3
NI-488.2M UM for Windows NT
ENOL (2)
ENOL usually occurs when a write operation is attempted with no Listeners addressed.
For a device write, this error indicates that the GPIB address configured for that device in
the software does not match the GPIB address of any device connected to the bus, that
the GPIB cable is not connected to the device, or that the device is not powered on.
ENOL can occur in situations in which the GPIB board is not the CIC and the Controller
asserts ATN before the write call in progress has ended.
Solutions
•
Make sure that the GPIB address of your device matches the GPIB address of the
device to which you want to write data.
•
Use the appropriate hex code in
ibcmd
to address your device.
•
Check your cable connections and make sure at least two-thirds of your devices are
powered on.
•
Call
ibpad
(or
ibsad
, if necessary) to match the configured address to the device
switch settings.
•
Reduce the write byte count to that which is expected by the Controller.
EADR (3)
EADR occurs when the GPIB board is CIC and is not properly addressing itself before
read and write functions. This error is usually associated with board-level functions.
EADR is also returned by the function
ibgts
when the shadow-handshake feature is
requested and the GPIB ATN line is already unasserted. In this case, the shadow
handshake is not possible and the error is returned to notify you of that fact.
Solutions
•
Make sure that the GPIB board is addressed correctly before calling
ibrd
,
ibwrt
,
RcvRespMsg
, or
SendDataBytes
.
•
Avoid calling
ibgts
except immediately after an
ibcmd
call. (
ibcmd
causes ATN
to be asserted.)