Support for Old Vibrating Sample Magnetometers

[ldc123]

Hello.

I am a relative newcomer to LabView and I am trying to get some support for a few older Vibrating Sample Magnetometers (VSM) on behalf of my employer.  These machines are quite old and, although they have GPIB connectivity, I am having difficulty in being able to control them using LabView.  Although they use the IEEE-488 GPIB standard, they were built before the introduction of the Standard Commands for Programmable Instruments (SCPI), rather than the newer 488.2 standard.  As such, they work with their own proprietary commands, which are proving impossible to find.  I have a working LabView program that was written by a university student for a master's degree in physics.  However, I cannot communicate with the individual components, such as the gaussmeter, power supply, etc, using measurement and automation explorer.  They don't even respond to an "*IDN?" query without timing out, which I thought was standard.  I have tried lengthening the timeout time and tried to use drivers for similar instruments.  My question to anyone out there is, do you have the drivers or the programming manual for any of the components listed below?  The Vibrating Sample Magnetometers were built by the now defunct DMS/ADE.  The current owners of DMS/ADE can offer little support for such old equipment.  Likewise, is there something else I can try in lieu of these drivers and commands? 

Devices:  1.) DMS Model 1660 VSM, 2.) DMS/ADE VSM Model 4, which includes the DMS/ADE model 32KP gaussmeter with its own GPIB port.

Thank you for your time,

Liam

[nnarra]

Hello Liam,

I have been using LabVIEW from 6 years and communicated with several instruments with Serial, Ethernet, USB and GPIB IEE-488, 488.2 standards. For all these communication, always  instrument manufacturer provided communication manuals which tells in detail about command set to be used, responses for commands etc.

As per my knowledge, if you want to communicate with any instrument using NI VISA for GPIB, you should have the command set for your instrument. Without this, we cannot develop any LabVIEW drivers. So in your case, at this stage please talk to your current owners of instrument to get information about commands, GPIB address of your instrument etc. Then only we can help you with driver development.

If you further need any details, please write here.

Thanks,

Naresh Narra,

India LabVIEW Developer League Member

[ldc123]

Hello Mr. Narra.

Thank you for your timely reply.  I am still working to get documentation for that instrument, but I am not sure if it is possible.  If anyone here has any documention, I would really appreciate it.  However, I do have original programming documenation for a Lakeshore 7300 VSM controller.  I have been able to handsake using the IDN query in the interactive control.  Likewise, I have made sure to set the transfer speed to normal, disable the high speed (due to the fact this device is about 20 years old), disabled the EOI assert, and I am now trying to enter the correct end of string character.  According to the documentation, the terminating character for this device is carriage return line feed (CrLn).  I am having trouble understanding the help articles on how to use the ibcEOSchar subset of the ibconfig command.  I am not sure how to correctly enter this in hex.  If you could help me with this problem, I would be very greatful.

Thanks,

Liam

[Trevor-B]

HI Liam, 

There is a built in string constant in LabVIEW for CRLF. This KB details it, as well as describing the hex value: http://digital.ni.com/public.nsf/allkb/5A5A050A3019A573862575F30061D49B

[nnarra]

Hi Liam,

I had gone through several GPIB 488.2 Traditional commands and ibconfig is one among several commands and used for Changing the software configuration parameters.

It takes 3 parameters as inputs which are ud (Interface or device unit descriptor), option (A parameter that selects the software configuration item) and value (The value to which the selected configuration item is to be changed).

Here, options are commands like IbcEOSchar, IbcEOScmp, IbcEOSrd etc.

Among these, IbcEOSchar is an 8 bit option to set End Of String Character. As Trevor mentioned, you can use these string functions directly or you can use Hex values also if you want to use combination of various carriage return, linefeed characters based on command set.

If any issues, write here.

Thanks,

Naresh Narra

[ldc123]

Hi Again

Thanks for the input.  I have tried to input the carriage return line feed in measurement and automation explorer to 1310, the decimal representation of this end of string character.  However, it only allows me to enter 3 numbers, and no letters.  If someone knew the solution to this, it may solve the problem.  Likewise, I have found the IbEOSchar under Ibconfig.  However, I do not understand the help article that well.  I know the hex for carriage return line feed is 0d0a, but I am not sure how to input it in this context.  I'm assuming that I want bit A enabled, bit B disabled, but I am not sure about bit C.  I also don't understand the example where the article shows the 0x140A, what exactly is the machine being set to do?  Mr. Narra, if you could provide a bit more insight for setting the IBEOS commands, that would be of great help.  The article discussing the IbEOS command is here: http://digital.ni.com/public.nsf/allkb/3AA75CCAC94E18BB862564F00079D2AD

Likewise, to Trevor, I will try to insert the graphical carriage return and line feed commands into the attached GPIB communicator VI. 

Thanks for the input,

Liam

[nnarra]

Hi Liam,

As per GPIB 488.2, as I already mentioned, the ibEOSchar under Ibconfig is an 8 bit value so it will take value from 0 to 255 for which 3 number width is sufficient. Measurement and Automation Explorer also works in the same way. EOS byte value under Termination Settings section of GPIB settings accepts a decimal number from 0 to 255 and it will not allow any character and also value more than 255 as its field is limited to 3 numbers and even if you enter a value more than 255, it will be automatically changes to 255.

So, As per 488.2, You cannot give both carriage return and linefeed characters together and you cannot use the same in MAX also.

Try framing your entire command with EOS as per built in LabVIEW carriage return and linefeed functions and use GPIB Write.vi to send this entire frame. It may work.

Also, I would like to see your VSM's communication manual and understand how these commands have been implemented.

Coming to IBEOS command, its easily understandable and its used to Configure the end-of-string (EOS) termination mode or character. It have low byte and high byte.

Low byte is always an 8 bit EOS character and high byte can take three forms which are A, B and C. Also High byte can have values with combination of A,B or C.

For Example, ibeos (ud, 0x140A); means, Configure the software to end reads on newline character (hex 0A) for the unit descriptor. Here high byte is a combination of A and C where as low byte is the HEX equivalent of ASCII Line feed character.

Regards,

Naresh Narra

[Erik]

I know this is an old thread, I just saw it by accident. Maybe this response is of use to anybody else looking for answer to similar questions in the future.

If anyone needs help with old DMS or ADE Vibrating Sample Magnetometers or any of their components, we are happy to provide help directly.  This includes answering any questions about communication through LabVIEW. Please contact us through 

http://www.microsense.net/customer-support-vsm-support.htm 

Erik Samwel

MicroSense LLC

Director VSM Business.

[crash_override]

The support page no longer loads. Is there still a way to get support for my DMS 1660?

[Erik]

Please contact me directly by e-mail at erik.samwel  @ kla.com