Keep getting EABO and EBUS errors in ibic, cables are fine, devices are fine...

[kshores]

I get these errors even when trying to find listeners. I already know what the addresses
for each device are, but I can't talk to it. A
standard example:
: set 488.2
488.2 (0) findlstn 3,4,5,17,18,29,28,29,30 3
produces:
[d130] (err timo srqi cmpl cic atn)
error: EABO
count: 0
(should be devices at PAD's 4,18,29)

Cables are good, devices are on, their self-
diagnostics all check. I've tried changing term. read on EOS, set EOI with EOS, type of compare on EOS, set EOI -last byte. Any ideas?

[Kim L]

There is a website that lists common GPIB error codes and solutions. You may check there for some things to try. You'll find the link below.

http://ae.natinst.com/operations/ae/public.nsf/fca7838c4500dc10862567a100753500/2fa525a8585a92e9862566ee002a3755?OpenDocument

Here are a couple of suggestions from that page.

Verify that all instruments are operating correctly, and that the ones you wish to communicate with are indeed powered-on.

Disconnect all instruments and connect them one at a time to determine if one instrument is causing the problem.

Check for loose or faulty cabling, and make sure that at least 2/3 of your instruments are powered-on (this is a requirement of the IEEE 488 specification).

If the timeout period is too short for the driver to send command b
ytes, increase the timeout period.


Make sure that your messages consist of commands that the instrument understands. Check your device's user manual for a list of possible commands.

Verify that you are using the correct termination method for your instrument. Byte count (where you expect to receive a certain number of bytes in a message) is always used, but some instruments use EOS and byte count, some use EOI and byte count, and some use only byte count. Check your device's user manual for the possible termination methods to use with your instrument.

If EOS is the termination method, then be sure to append the termination character to the end of your message. You can specify the termination character in the GPIB Configuration Utility, but the NI-488.2 driver will not automatically append it for you!

Lengthen the timeout period for I/O operations using the ibtmo command.

If you receive all of the data and get an EABO error, then look for a particular end of string character (e.g.
, linefeed or carriage return) and configure the GPIB board to terminate the read on that character using the ibeos function.

Kim L.
Applications Engineer
National Instruments

[kshores]

Re-seating the interface card did the trick. I think I was able to talk to the gpib card,
but the pins not seated properly seemed to affect any attempts to communicate with
other devices. Everything now works as it should, Beta version 0.8 driver for Linux
seems to be running pretty solid...