hp 70950a osa

[antony_sc]

Hi, I am new to this forum, I seek for help to create a basic Labview program to communicate with an old HP70950A optical spectrum analyser, connected via GPIB to a Win98 computer where Labview 6 is installed. there are no driver available, but just the HP-BASIC manual. I would like to get, via normal READ-WRITE commands, the cursor peak amplitude and eventually the wavelength. Any additional command to control the instrument will be welcomed.

I will get this data as function of measured power from Agilent 8163A multimeter,, for which there are the drivers already.

Thanks

Antony

[smercurio_fc]

We don't have the manual for that instrument so we can't really help you on what commands are required to get the data you seek. You would need to look in the manual that you have. There's an example that ships with LabVIEW that's called "LabVIEW <--> GPIB" that you could use to test out the communication. Do you know if the 70950A is IEEE488.2-compatible?

You mentioned that you have an instrument driver for the 8163A. Is it this? Neither of those is for LabVIEW 6.1 so if you needed a 6.1 version you could put in a request to downconvert it.

As for the code itself you will need to get a basic outline done of what you want the program to do and how one should operate it. Are you collecting data over time? Do you need to graph it? Do you need to save it to file? 

If you have not done so I would recommended that you go through the tutorial(s) and look over the material in the NI Developer Zone's Learning Center which provides links to other materials and other tutorials. You can also take the online courses for free.

[antony_sc]

thanks for the first answer. the instrument is IEEE488.2 compatible, and it is connected to a 70004a HP display, with which I can communicate (it responds to *idn?). What I need to do is to get the peak amplitude of the cursor. I know how to draw graphs and deal with the data in Labview, but no idea how to convert the HP-commands. Here is the manual the company sent to me. I would like some translation of the command PEAKS and MKPK. thanks

[antony_sc]

Thanks, now I am able to send commands using the SEND box in GPIB 488.2. It seems slowing going well. Now that I am able to control the instrument, but how to get the data from it? Which Labview box allows me to make a query in GPIB?

For example, if I send IDN? in the VI program, how can I get the answer as a string? I tried with RECEIVE box, waiting even long, but the output is empty.

[Dennis_Knutson]

Why are you sending *IDN?. That command is not listed in the manual. What is in the manual you posted is ID.

And what do you mean by 'box'? There are functions and icons in LabVIEW but I would recomend that you keep it simple at the beginning and try all of the commands in MAX. Just right click on the instrument and select 'Communicate with Instrument'. You can also launch the VISA interactive control.

p.s. If possible, you should be using the VISA functions and not the low level GPIB ones. 

[antony_sc]

i mentioned IDN? because it is the easier query. I would like to get the translation of any command ending with ? like MKWL?I have labview 6, and by BOX I meant function, those appearing in the function palette. sorry for the wrong lexicon

[Dennis_Knutson]

IDN? cannot be used if it's not supported by the instrument.

Just try ID in MAX. Execute a query and see if you get a response. You might have to add a terminator such as \r,\n, or both. I did not read enough of thr manual to see if it's required.

[antony_sc]

10 CLEAR 723 Initialize analyzer.

20 OUTPUT 723;"IP;SNGLS;TS;"

30 OUTPUT 723;"CENTERWL 1300NM;SPANWL 10NM;RL -5DBM;" Set measurement range.

40 OUTPUT 723;"TS;" Sweep trace A.

50 OUTPUT 723;"MKPK HI;" Mark highest signal level.

60 OUTPUT 723;"MKWL?;" Return wavelength at marker.

This is an example of the code I want to implement in Labview. I am now able to execute line 10 to 50, using SEND commands to the single GPIB device. The problem is line 60

I can send MKWL? as a command, but how can I get the output? With MAX it works (also ID? command works) by pressing the QUERY button, but which function to use to make it in the Labview program? RECEIVE following the the SEND does not work. I tried playing with time, to see if it is a problem of communication, but it is not.

Thanks

Antony

[smercurio_fc · Accepted solution]

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antony_sc wrote:

 which function to use to make it in the Labview program? RECEIVE following the the SEND does not work. I tried playing with time, to see if it is a problem of communication, but it is not.

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My eyesight is bad enough already, so if you could be kind to us old folks, could you use a normal-sized font in the future? 

Well, the Receive function would be the equivalent function in LabVIEW. What do you mean by "it doesn't work"? Do you get an error? If so, what is that error? Still, I would concur with Dennis that you should be using the VISA functions.

[mrish]

Hey,

I'm working on the same product. I manage to read the data only using time delay.

Can someone attached a write \ read scheme using SRQ\RQS or status bit register pollling?

I've tried to implement them based on the on the examples of VISA event handle but it didn't work.

Can someone show me a working scheme with just need message change?

thanks