GPIB Synchonization with DAQ

Currently I'm in the position of implementing a software-timed solution so that my data acquistion hardware (analog inputs) can be synchronized to an average reponse time for a GPIB query to an instrument. Yes, this sounds like fun! I was wondering, I seem to remember the GPIB analyser software (CVI app) had timing information for the various line state transitions. In general, is there any way to get hardware timing information from a NI GPIB controller?? The reason for this approach is that the DAQ AI samples may be corelated to the instrument data - we don't know at present!

Hello-
The GPIB analyzer software does have a triggering menu available. However, there is currently no API for the analyzer available. However, it might be possible to tap the EOI line with a second GPIB cable. Then, a DAQ card can monitor the progress of the GPIB communication. There may be some easier software solutions as well. Try using Datasocket if it is necessary to have interprocess or intermachine communication. There are plenty of Datasocket examples in CVI and LabVIEW.
Randy Solomonson
Application Engineer
National Instruments

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Hi muthu,
we also have a problem: to less information…
- What is connected to your laptop?
- What is "it" in "it displays building VI"? Do you use the DAQ Assistent ExpressVI?
- What means "plz"?
And could you please put less text in the title of your message and more text (with relevant information) into the message body?
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Need help with daq problem

Hi,
I need to generate a clock with a period of 20 micro seconds, duty cycle of
approx 20% and a data line as well as an address line all linked to the clock
pulse.
I have tried many different solutions, all using the Daq PCI-1200 but nothing
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Hallo, Ken,
Du meintest am 20.02.00 zum Thema Need help with daq problem:
> I need to generate a clock with a period of 20 micro seconds, duty
> cycle of approx 20% and a data line as well as an address line all
> linked to the clock pulse.
You'll need an external clock, expecially under Windows.
Windows ticks with appr. 18 Hz, and the CPU tick isn't always available
when Windows tasks multi.
Viele Gruesse!
Helmut

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GPIB Labview NI-DAQ, Micro 1401 and Windows 7

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b) If it is, will it work in Windows 7 please?
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If you mean this then I cannot see any easy way of making it run in LabVIEW... unless you have an older version of the Micro1401 that has a GPIB interface?
Mark B
===If this fixes your problem, mark as solution!===

Why do error comes when trying to use NI ISA GPIb and NI DAQ card (both PnP)together while they work well when one at a time?

we configured gpib pnp and at-mio-64e3 cards (isa) in the same pc.gpib function was invoked to take the device to remote and listen mode.now when daq function getDeviceInfo is called the remote mode of the device is removed and after this it always shows no gpib board until pc is rebooted

Hi,
I have some questions:
What OS are you using?
What driver versions?. You can find the driver versions in the Windows Add/Remove programs utility. DAQ driver is NI-DAQ anmd GPIB driver is NI-488.2.
Is there any error code?
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Hello Seth,
Thank you for contacting National Instruments.
What exactly do you mean when you say that your GPIB card is not working? Is it still showing up in Measurement and Automation Explorer (MAX)? Is it showing up in your Device Manager? If you can see it in MAX, what happens when you try to open a VISA Session? Can you communicate or does it time out?
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GPIB issue with solartron 1260 and 1287

Our old computer of Solartron 1260 and 1287 was down recently, I managed to transfer the GPIB card to a computer with Windows 2000 system, and installed NI-488.2 v2.7.3 driver. It seems the computer recognised the GPIB. However, when I tried to run the CorrWare, the computer automatically restarted without any warning. I wonder what's the solution for this problem? Any hint for additional installation I might missed?

More weird thing is I tried Communicator to send query by clicking the 'query' button of the device 0, for just once the string received was ‘Schlumberger balabala’
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{Edit} Yup http://www.solartronanalytical.com/Support-Center/FAQ/FAQ-General/How-can-I-troubleshoot-GPIB-proble...
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You probably do not have a problem here. Things work as advertized.
I love the "If this does not help then consult the National Instruments Troubleshooting DAQ and GPIB Installation Problems web page. " (No hyperlink provided) statement
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hi
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Could not execute target data map file 'untitled_rtwin_win32\untitled_targ_data_map' or it does not exist. Stop the target, delete the untitled executable, rebuild the code,and try again. Note that execution of external mode requires the build directory to be present...
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Untitled.jpg ‏130 KB

Hi Mahmudur,
what does MathWorks say about this error message?
Best regards,
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Hello,
I'm new here so I apologize if I posted this on the wrong board
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Attachments:
PID while.vi ‏100 KB

My problem is the following. Both of the NI-DAQ I placed using DAQ Assist, require to be in a while loop.
-If
I place them in separate loops, I have the problem of passing
information between the Input NI-DAQ and the PID, and also between the
PID and the Output NI-DAQ.
This is the best option---Use QUEUE or Functional global or something else to tranfer the data to and fro
How do I make that QUEUE or Functional global?
-If I place them both in one big loop, an error occurs saying that the selected buffer size is too small (Error -200609).
Have
you tried increasing the buffer? Is the acquisition happening
parallelly (means to say the first DAQ not wired (error terminal) to
second DAQ)
Well the buffer is, at least how I understood it, the option Number of Samples when in Continuous Samples mode. Concerning the parallel acquisition, do you mean I should wire the error ports of both of the DAQs?

How do I set a PFI to High on a 6602 Board with DAQ Traditional

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I am using LabVIEW 8.5 on 32-bit Windows XP with an NI 6602 DAQ board. In the past I've used DAQmx but for compatability with older software I need to do a few simple things using Traditional DAQ, which I have never used. Specifically I would like to make a simple VI that sets PFI 5 to high when the user presses a button and then low when they press the button a second time. How do I set PFI 5 for output and then write true to it?
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Solved!
Go to Solution.

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Apparently its as simple as using the Write to Digital Line VI. However, the non obvious thing is the port width of the 6602 board is 32 not the default 8. Buried in the LabVIEW help files is a list of physical port widths that one must stumble upon. Like the bat cave. In the attached image of the super simple VI I've made the 16 refers to PFI 16. Good to know.
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Attachments:
write_low.JPG ‏5 KB

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Thanks in advance,
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LV 8.21: strange behavior with DAQ tasks, parallel running VI's and shift registers

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I have made a VI using DAQmx vi's. The VI uses shift registers to store DAQ tasks and other (internal) information. I have implemented several modes of operation (enum control with a case structure) like 'init', 'read AD', 'config AD' etc. If I use this multi mode VI in a single main VI everything work as expected. I have attached a jpg that shows one example where the DAQ VI is called from 2 parallel running while loops. One loop aquires the data (LOOP 1) while the other loop configures the aquisition task (LOOP 2). If I implement the same thing by putting LOOP2 in a different VI that runs seperately from the first VI I get an error message (200428):
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Measurements: Value passed to the Task/Channels In control is invalid.
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Attachments:
problem.jpg ‏30 KB

1. In general, this kind of technique is something I've been using successfully for years. (Ben recently wrote up a very nice treatment of these "Action Engines" as a "Community Nugget.") So I don't start by expecting this to be a bug in the LV execution system.
2. Your description of the problem sounds almost backwards. You say you manually start the 2nd vi ("Config AD") *after* running the 1st vi ("Read AD"). Seems like you'd need to do the Config 1st and then do the Read, right? I kinda suspect you actually did it in the right order, but described it wrong.
3. The next likely scenario is that the Config failed, but you didn't trap the error and were unaware of it. Then it makes sense that the Read would also fail.
4. A couple issues I regularly deal with in these DAQ Action Engines is internal error handling. I often keep a shift register inside to store errors generated inside the Action Engine. But it can get a little tricky doing sensible things with both the internal error and any other error being wired in as input.
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What is the best method to query for older GPIB equipment with ID? and newer with *IDN?

Good day,
I am writing a test executive where it needs to scan the bus for support of older (HP/Agilent 856x series) and newer (Agilent 440x and 444x series) spectrum analyzers. *NOTE* I originally posted this question in my NI Community blog. I apologize for redundancy but someone recommended I re-post here.
The first frame looks for the newer analyzers with *IDN? then if that fails sets the boolean in the error cluster to TRUE. The next frame then uses the error cluster's boolean to decide whether an older HP analzer is connected instead using ID? query. Disclaimer: the second frame is a clone of the ID query of the 856x Initialize VI. I just want to use what already worked - no reinventing the same wheel?
But, lo and behold, it doesn't work as expected. If I have the frames in this order and connect a HP8563E the GPIB time's out error. This code works with the newer 4407 or 4440 since the *IDN? query passes and the second frame is not executed.
Now, when I move the second frame to become the first frame and run it with HP8563E the query works but will have a GPIB timeout if I have the 4407 or 4440 connected.
Long story short, how do I support both older GPIB ID? and newer IDN? in my code?
I have attached the query VI created with LV 2012.
Many thanks!
Aldrin
Attachments:
Query ID and IDN.vi ‏11 KB

I think Michael Aivaliotis of JKI and NI have an elegant solution:
https://decibel.ni.com/content/groups/large-labview-application-development/blog/2015/05/14/what-is-...
Cheers!
Aldrin

GPIB Synchonization with DAQ

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