iberr = 2[0x2] when using ibwrt() to communicate

[flyby]

Hey,
I have been trying to communicate with a Spectrum Analyzer via GPIB.  I have a string of ibwrt() commands in my code but I keep on getting an iberr = 2[0x2] at the very first ibwrt().  I can not figure out to solve this issue so any help would be welcomed.  Thanks.

[mvr]

Your GPIB card is telling you that the DTAS line is active.  This would normally indicate that some other device on the GPIB bus is acting as the bus controller. 

You might want to try and talk to the device directly.  Open Measurement and Automation Explorer.  On the left side expand Devices and Interfaces.  Expand GPIB0 (assuming your card is installed as the default name).  If there are not any instruments shown, then Scan for Instruments.  You should see a list of instruments.  If you right click on the instrument and select Communicate with Instrument, you can try sending commands directly to the instrument.  You can also see the status of the GPIB interface lines in the window.

[flyby]

When I used the Measurement and Automation Explorer and select Communicate with Instrument, I get the following error when I send an *IDN? query:

iberr = EABO

EABO indicates that an I/O operation has been canceled, usually due to a timeout condition after a GPIB read.  Before reading from the instrument, verify that the GPIB command you are sending is understood by your device and instructs it to place data in its output buffer.

However, I am able to write commands to the spectrum analyzer; for example, the desired center frequency, but I am not able to read from the instrument.  Is there anything that can be suggested to help solve this issue?

[mvr]

It looks like the "read" is not terminated correctly.  In the interactive communication windows there is a button marked configure EOS  Try changing the setting for Terminate Read on EOS.  If that does not work, you will want to look up the type of terminator that this instrument uses and see if you can use the compare settings to terminate the read input correctly.  You can also right click on the GPIB card in measurement and automation explorer and turn on NI-SPY.  This allows you to sniff the GPIB connection to see exactly what is going on.

[flyby]

When I use the NI Spy I get:

ibrd(UD0,'''',2000(0x7D0))

So obviously I am having reading anything from the spectrum analyzer.  I even made sure that the box marked "Terminate On EOS" was checked in the device configure panel.  Is there some parameter or some box that I am forgetting to mark when configuring the device?

[mvr]

It looks like the analyzer never responded to your command.  I assume you were looking at a command you sent interactively from the Communicate with Instrument dialog box.  You could try adding a \r or \n to the end of the command.  But since you could set the center frequency without having to do that, it probably will not change anything.  You could post the nispy listing for an entire session, including the commands that work.  Maybe there would be a clue there.

Message Edited by mvr on 06-08-2006 02:08 PM

[cybrm110]

I was having a somewhat similar problem with an HP6632 PS and it turned out
that the query string I was given as an example from a CVI course was a
variation from what the instruments documentation required. Double check
your instruments programming manual first, you may find the answer there.

"flyby" <x@no.email> wrote in message
news:1149626416154-375061@exchange.ni.com...
> When I used the Measurement and Automation Explorer and select
> Communicate with Instrument, I get the following error when I send an
> *IDN? query:iberr = EABO
> EABO indicates that an I/O operation
> has been canceled, usually due to a timeout condition after a GPIB
> read.&nbsp; Before
> reading from the instrument, verify that the GPIB command you are sending
> is
> understood by your device and instructs it to place data in its output
> buffer.
> However, I am able to write commands to the spectrum analyzer; for
> example, the desired center frequency, but I am not able to read from the
> instrument.&nbsp; Is there anything that can be suggested to help solve
> this issue?&nbsp;

[echo5183]

I have a question in communicating with hp6632, too. I write 'VOLTage 4' to 6632A by LABview, but it is not workable and 6632A is locked. Can I share your method to communication with hp6632? THX.

Message Edited by echo5183 on 03-19-2008 08:22 PM

[mvr]

wow, old threads live on. You have posted in the CVI forum, you would normally have better luck in the labview forum but I will take a crack at it.

If you are using a 6632A try this instrument driver 6632A

There is also a different driver available if you are using the 6632B model.  There are hundreds of instrument drivers available by selecting NI Developer Zone from the tabs at the top of the page and then choosing Instrument Drivers in the lower right corner.

Good Luck

[edit: fixed A's and B's]

Message Edited by mvr on 04-09-2008 08:13 AM