How to get MAX to "Scan" for my old instruments?

[charles1]

I have an HP 5386A frequency counter and issues with MAX version 3.1.0.3021

The 5386A is at GPIB address 5

My issue is that MAX "sees" my 5386A everywhere:

I know that the 5386A is an old instrument and does not respond to the "*IDN?" command:

http://forums.ni.com/ni/board/message?board.id=170&message.id=144535

I know that other HP frequency counters seem to have this same issue with MAX:

http://forums.ni.com/ni/board/message?board.id=140&message.id=15157

So how do I get MAX to work correctly with my legacy instruments?

Is there a way to get MAX to send a different command to identify an instrument?

Thanks.

[nyc_(is_out_of_here)]

As far as I know MAX doesn't work with the older equipment.
Prior to my joining my current company, they bought some old HP counters and power supplies for a test rack,
so I have the same problem you do.

If you want to test out commands to these older equipment, you will have to use the DOS-ish interactive control ibic.

If someone knows of a workaround, I would love to know.

[Albert.Geven]

The device will not be recognized by max because it does not respond to *IDN, in fact this is an scpi command and the instruments are older than scpi.

BUT... MAX should not have more than one line that is not recognized, I normally get just one line with an instrument that old.

Can someone from NI respond ...

[ScottieB]

It appears that your instrument at PAD 5 doesn't respond to *IDN?, which is okay.  The reason it shows up so many times is probably because it supports secondary addressing (think of it as a sort of subaddress).  So you have an entry for PAD 5, SAD 96, one for PAD 5, SAD 97, one for PAD 5, SAD 98, and so on.  You can check your documentation to see that your instrument does use secondary addressing.

Scott B.
GPIB Software
National Instruments

[charles1]

The 5386A is one of a series of frequency counters. The others are the 5384A and 5385A.

The manual for the 5386A is available from the Agilent site at:

http://cp.literature.agilent.com/litweb/pdf/05386-90010.pdf

The manual for the 5384A/5385A is available from the Agilent site at:

http://cp.literature.agilent.com/litweb/pdf/05384-90006.pdf

There is no mention of any sub address in these manuals.

Using the National Instruments "Interactive Control" utility the 5386A recognizes HPIB commands and responds.

The 5386A does not seem to interferer with other instruments on the bus.

Why does MAX look for subaddresses on this device?

Is it possible to prevent MAX from looking for subaddresses?

[ScottieB]

MAX looks for subaddresses because each of the secondary addresses could represent a distinct "instrument" in one large box, all placed at one primary address.  It is possible that you would want to send a command to a specific sub address.  It's not possible to disable this feature, but I don't know why you would need to.  We intend MAX to be a "get up and running" sort of utility for GPIB to make sure your instruments are detected.  Yours clearly are.  I do see that it does a poor job of indicating that the devices are recognized at secondary addresses.  I'll see what I can do to change that in the future, but as far as I understand you're all set for now, unless you have further questions.  Let me know.

Scott B.
GPIB Software
National Instruments

Message Edited by ScottieB on 03-07-2006 04:23 PM

[charles1]

No as a matter of fact I am not "set for now" because my instrument still cannot be recognized my MAX.

It seems that the VI for the frequency counter does not seems to work with when MAX declares a primary address as non-functional.

Is there any way for MAX to recognize that a primary address is in use by a non 488.2 instrument?

[Dennis_Knutson]

Your instrument is recognized by MAX. If it wasn't, you wouldn't have the instrument listed at all and all of those listings for the secondary addresses. The fact that the instrument does not respond to the *IDN? prompt does not mean there is a problem. MAX does not declare anything as non-functional if the id query fails and doesn't care if the instrument is 488.2 or 488.1. When you use the driver, what happens exactly? Do you get an error and if so what is the error code?

[GoBlue]

In my case, it isn't MAX that declares the ID as non-functional, it's the frequency counter getting locked up.  A power cycle on the counter would fix it.  I had to stress to everyone that if they have a HP/Agilent counter in the system, not to do a Scan for instruments.  My error was normally an Invalid GPIB command, and I think it locked up counter's GPIB bus because MAX kept pounding it 32 times.

The biggest problem I saw, was that MAX 2.x versions would work fine, but it was versions higher than 3.x that started the secondary addressing problem.

[daijoubu]

I've had a similar issue with a Behlman AC source in one of my test systems.  I've learned that if I want to scan the instrument bus with MAX it's better to turn the AC source off first, then scan, then power the instrument back up.  I hardly ever scan the bus because MAX remembers the results from the last scan and the configuration of my test system rarely (ideally never) changes. 

As a feature request, can we get the ability to tell MAX to not scan certain addresses?  Ideally I'd like to define the command to use for each address and if undefined default to *IDN?, but a simple blacklist type feature would be adequate in this case.