"Addressed to Talk with Nothing to Say"

[jshsu]

I'm trying to interface a network analyzer (Agilent 8772D) using GPIB with LabView but I'm having a few issues. I have just started using GPIB and made a very simple test program that writes a command and then reads any response from the target device. I tested it with my power supply (Agilent E3631A) and the power supply responded to all the basic queries (*IDN?, *RST, *TST).

However, when I attempt to use it with the network analyzer, I receive a time-out error every single time. The network analyzer displays "Caution: Addressed to talk with nothing to say". I've tried googling with inconclusive results. Is this a problem with Labview or the network analyzer?

Thanks,
Jeremiah

[alipio]

Hi jshsu
I can not find Agilent 8772D.
Check if model is OK and if it is SCPI compliant. If not, the equipment will not understand those commands, so will answer nothing or will give errors ( illegal command, nothing to answer, etc.)

Alipio

[Emilie S.]

Hi jshsu:

As Alipio has mentioned, this sounds like an issue of sending the wrong command to the instrument. It is possible that this Network Analyzer does not respond to *IDN?. First find a command in the product's manual that you know will send a response back, and you can try your program again.

Also, I would recommend testing communication in Measurement and Automation Explorer (MAX). Here if you have an NI GPIB board and NI-VISA you can open a VISA session and try to communicate with the instrument, or you can right click on your board under Devices and Interfaces and select Interactive Control to try ibic communication. Please see the attached Interactive Control screenshot.

Thank you,

Emilie S.
Applications Engineer
National Instruments

[ScottieB]

I've never heard of an instrument giving such a specific error, but it makes perfect sense. The way a "read" in GPIB works is that the controller (usually your PC) will "address" the bus. Say your instrument is at address 6. This means that the controller will send a command byte out that means "address 6, it's your turn to put data on the bus" or alternately "address 6, talk". Thus, the error that you're seeing on your instrument is that it knows it's addressed to talk, but it has no data to provide at this point. That's either because you didn't query it at all, or you didn't query it with something it understood (maybe it doesn't understand *IDN?). So it has nothing to say at this point.

As the previous poster points out, make sure that the queries you're sending to the device are correct; see its user manual.

Scott B.
GPIB Software
National Instruments

[kmaulwurf]

I have the same error. I own an old “HP-8753A” NVA and I want to read my measurement data by GPIB with my computer. I use a LabView program from one person who used this at the same NVA type many years ago. At the computer should all install correctly. My NVA use the address 16 and I see this in MAX too.

My problem:

I can read from the NVA but I get information like my below s2p file. My frequency doesn’t change. The frequencies in the file are always my start frequency 300 KHz. At the reading moment I see “Caution: Addressed to talk with nothing to say” at the NVA display.

My NVA use 201 measurement points and my received S2P has this number too.

------

! 10:50:23 3/13/08      
# Hz S MA R 50   
3.00E+05    0.00E+00    0.00E+00    1.36E-03    -9.42E+01    3.43E-04    -1.51E+02    9.29E-01     2.42E+01
3.00E+05    0.00E+00    0.00E+00    8.04E-05    -1.24E+02    3.98E-05    -6.37E+01    9.33E-01    -2.71E+01
3.00E+05    0.00E+00    0.00E+00    5.34E-05    -7.57E+01    5.36E-05    -1.39E+02    9.09E-01    -5.04E+01
3.00E+05    0.00E+00    0.00E+00    2.02E-04    -1.02E+02    1.26E-04     4.00E+01    9.24E-01    -7.36E+01
3.00E+05    0.00E+00    0.00E+00    8.45E-05     1.39E+02    3.02E-05     1.02E+01    9.45E-01    -9.88E+01
3.00E+05    0.00E+00    0.00E+00    1.59E-04     1.03E+02    1.14E-04    -1.20E+02    9.55E-01    -1.25E+02
3.00E+05    0.00E+00    0.00E+00    8.88E-05     1.28E+02    7.81E-05    -1.67E+02    9.50E-01    -1.51E+02
3.00E+05    0.00E+00    0.00E+00    4.93E-05    -2.93E+01    2.05E-05     4.21E+01    9.39E-01    -1.76E+02

[A_Ryan]

kmaulwurf,

I have a couple of suggestions for you:

1.  Can you confirm the the PCI-GPIB card is working correctly?

2.  If so, can you try another instrument that you know works to confirm that proper communication exists.  I would also double check the commands being sent to the device, the commands for the instrument can be found in the user manual.

3.  Can you communicate with the instrument in MAX (Measurement & Automation Explorer) using the VISA test panels?

4.  Can you please include an NI-Spy Capture?  This will help us determine what commands are being sent/received by the device.

[kmaulwurf]

A_Ryan

It is funny, if I read with running NI-Spy it works without problems. If I close the Spy software is the problem still the same.

I do not really understand this behaviour?!?! 😕

[A_Ryan]

kmaulwurf,

Based upon your last post it sounds like you are having a timing issue.  NI-Spy slows down execution time to gather information.  Without any waits inside your application the program will execute as quickly as possible.  You may need to add a wait to your code to ensure that the device or the computer has time to "catch" up if need be.  If you already have waits you may want to consider increasing the wait time.

[Tech-o]

hello there,

i've read all your auggestion, very helpful.

i'm using a software test that works along with an 8753ES NA it uses a PCI GPIB card, this NA started today to pop up a message..."CAUTION: ADDRESSED TO TALK WITH NOTHING TO SAY". when i run the NI sw and scan for any instruments makes no sense to me that the first s/n number of my device didn't match with the s/n displayed by the query tasks, i just replaced this NA and use a ENA E5071C, the issue was done while i using a different device but it never solve for me the removed 8753ES issue, do you know if this device needs to be send for repair?

regards

Tech-0

[haju]

The "Addressed to Talk with Nothing to Say" message on the HP8753x screen is not necessarily a bug but a feature:

NWA occupies 2 GPIB addresses; 1 for the device itself, 1 for the display. GPIB name for the device itself is "Hewlett Packard...". GPIB name for the display is null. Once you press "Scan for Devices" in NI Measurement & Automation Explorer, all devices reply with their GPIB address and GPIB name. Since the address of the display is null, the bus indicates that the response of the display is not valid. However it's just a message, it does not affect to the functioning of the NWA or the display. You can get rid of the message by pressing any key in the NWA.

Br.

Juha Ritala