Gpib controller enquiry(gpib guru)

hi
i recently had a problem getting control of the atn bit but succeded with your help.
now although i can switch the atn bit by setting the controller in standby mode, i still cannot send data bytes. i found some info that said that i should address the 7210 to itself talk and listen. does that make sense to you? because it sounds strange
if so, any ideas??
thanks again

gts should work. It should transition you from an active controller to a standby controller. This deasserts ATN and allows you to transmit data bytes. I know that it works with the NAT7210. You should be able to look at the ADSR to see if the chip thinks it is a talker/listener. This could be a bug in the chip. You may want to contact the manufacturer for more information.
Disabling system control switches the direction of the REN and IFC lines in the transceivers. The side effect is that the REN line will be deasserted and all devices will enter local state.

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Re:on reply to gpib guru

hi. i am using the measurement computing gpib controller cb7210.2 which is ni compatabile.i am interfacing it with a microcontroller connected to the pc.Then i am trying to use a monitor program that is embedded in the microcontroller to perform remote access of instruments. i have managed to communicate with the instrument.now the problem is that i cannot make the distinction between data commands and interface commands.for eg if i send 3Fh and atn happens to be 1 this is interpreted as UNL if atn is 0 data command.i need to be able to have control when to send either right now i do not.
thanks again

Already answered on the appropriate thread. I am just responding to move it from "new" to "answered".

Application hangs without GPIB Spy running

During initialisation my application uses ibcmd() to send a 4 char string to set several special to type instruments to Local lockout.
This code runs perfectly BUT, only when GPIB Spy utility is running on the same PC. Without GPIB Spy running the ibcmd() function hangs, eventually timing out with iberr showing EABO (I/O Timeout).
To keep things simple, my question is really what effect (apart from timing issues)could GPIB Spy be having on the Applications GPIB operation?
Has anyone else experienced similar problems?
All comments welcome:-)

Hi GPIB Guru - thanks for your speedy and helpful reply!
Yes I do mean GPIB Spy, I am working on a legacy system based on Windows NT 4 and using NI-488.2M Version 1.30. It consists of dual NI PCI-GPIB boards and various instruments (Sig gens, attenuators, Spectrum analysers, RF Receivers etc.)
The whole system works fine apart from the initialisation phase where we set a GPIB programmable filter to local lockout. This consistantly fails without GPIB Spy running (and hangs the bus from there on) and always performs correctly with Spy running.
it uses function ibcmd() to send a 4 charcter string consisting of the following Multiline Interface Messages:
0x3E (UNL - Unlisten)
0x3F (MLA30 - My Listen Address 30)
0x11 (LLO - Local Lockout)
0x3F (UNL - Unlisten)
Today I tried splitting the string into its 4 separate characters and using ibcmd() on each one individually. This showed me that it hangs when sending the 0x3F character (set to listen on address n). I cant break it down any further - with Spy running this function call works; without Spy it hangs!) and of course without Spy running I cant examine the call (Schrodinger's Cat anyone:-)).
* I can pause on a breakpoint before sending ibcmd so it *cant* be an application speed issue.
* The filter is quite a distance from the PC and normally the GPIB is linked via fibre optic and 2 HP bus extenders. I have bypassed this setup with a *very* long GPIB cable
* The PC is very old and of low spec (so should be low speed).
* The filters were built special to type and there has been no firmware updates.
I see you make mention of *old* GPIB boards, is it possible that there could be a mismatch between old driver version and newer boards? or vice versa?
I am rapidly running out of ideas, do you have any other thoughts?

I2C USB 8451 ADS1100 read result incorrect

Hi,
I have connected ADS1100 (http://www.ti.com/lit/ds/symlink/ads1100.pdf) to measure the temperature sensor output voltage of LMP91000 (http://www.ti.com/lit/ds/symlink/lmp91000.pdf). In LMP91000, I have write 0x7 to switch the MODECN to TIA ON mode in order to measure the 'Temperature Sensor' appeared on pin 'VOUT' only.
1. Attached 'write to MODECN of LMP91000.vi' seems correct.
Then, I change the slave address to 0x49 of ADS1100 to measure the output code for the temperature voltage. There is one register named 'configuration register' which has a default data 0X8C. There is a two-byte 'output register' which is the output code of ADS1100.
2.Attached 'ADS1100 Read.vi' seems correct, but the read out data is incorrect, I think
The 1st byte on SDA line is the address and R/~W bit which is correct;
The 2nd byte on SDA line is the output upper byte. Here comes the problem——
there should be 9 clocks appeared on SCL line during the 2nd byte.But, I have 8 clocks during this byte. I cann 't find the ACK signal.
The 3rd byte on SDA line is the output lower byte. Here is another problem——
there should be an ACK (0) on the 9th clock, on the contrary, the ACK is 1...
The 4th byte returned the configuration register data, which should be 0x8C, but I cann't explain the wrong data appeared on the SDA line...
I have to set up the values every time I run the vi.
LMP91000 address: 0x48 MODECN register address: 0x12 MODECN register data :0x7
ADS1100 address:0x49 Numer of bytes to read:3
I/O voltage level:3.3V
Pull up resistor :10 K
I have searched on this forum to see if someone else have already solved this problem, but I did not get it.
Any suggestions or answers to these quesitions are greatly appreciated. Thanks a lot!
Sincerely,
Ivy
Attachments:
block diagram.jpg ‏24 KB
write modecn.vi ‏16 KB
write to MODECN register.JPG ‏66 KB

HI, GPIB Guru,
At first, thank you very much for your detailed explainations.
1.
Interpreting the two scope captures, I see:
write to MODECN register.JPG
100100000 = x48 Read Ack
000100100 = x12 Ack
000001110 = x7 Ack
ADS1100 Read waveforms.JPG
100100110 = x49 Write Ack
111110100 = xFA Ack
100110110 = x9B Ack
100011001 = x8C NAK
Yes, I have realized that from the second output byte, there seems one clock delay for each byte, which can explain your interpretation above. But according to the ADS1100's datasheet, when the last byte (the configuration register which is 0x8C) is read out, the SDA line should pulled down to 0 to gives an ACK signal, not a high NACK signal.
I have also attached the 'reading diagram from ADS1100'.
2.
It appears that your slave may be doing a clock stretch before the ACK bit can be set.
I found in datsheets of both ADS1100 and LMP91000 that they both operates in Standard mode (100Khz). Actually, I have slowed down the clock rate and didn't find any changes on the read waveform. If I didn't follow your idea, please let me know. Thanks again for your kind reply.
Sincerely
Ivy
Attachments:
timing diagram for reading from the ADS1100.JPG ‏76 KB

XNET and Dell Vostro

I've had a problem for quite awhile trying to use my Dell Vostro 1510 to connect to a PXI system but now it has become imperative that I get this to work since I need to make changes to a system offsite.
Once I load NI-CAN and NI-XNET, I can no longer connect to my PXI, Remote Systems goes away in MAX, error regarding "canexperts" is displayed, and no Software is even listed in MAX.
I have no problems when using my Dell desktop.
I've downloaded "Dependency Walker" and have attached the file. I've downloaded and installed all the latest drivers for MAX.
Not sure where to go from here. I need to get this laptop working with the PXI. Any clues would be appreciated!
Attachments:
NIMaxTS.txt ‏708 KB

I've attached some screen shots. NoCAN.jpg shows the software installed with just XNET.
Clickonsw.jpg shows the error message that appears when I click on the + in front of software.
NoRemote.jpg shows how MAX looks after I answer NO to the error message. I didn't capture it on the first picture but my remote system shows up before I install the CAN software. After, it disappears.
GPIB Guru, I believe there is only one version of XNET (1.0) which includes CAN 2.7. A different message used to occur with earlier versions of CAN (a dll failed to initialize or something close).
I'm leaning toward a problem with the BIOS of the laptop. I'm not going to install on another machine since it works on my desktop. The main issue is that I need it on my laptop because I have to travel out of the country to make changes on a PXI system and I cannot lug a desktop with me! Unfortunately the only other laptop available here at work is the exact same model that we use for PLC type machines.
I'm hoping I can find a workaround for this issue.
Thanks for the input! Any more thoughts are appreciated.
Attachments:
NoCAN.jpg ‏530 KB
Clickonsw.jpg ‏85 KB
NoRemote.jpg ‏36 KB

NI-Device Setup Problem

We have Device computer(PentiumII) with Windows NT 4.0 OS on it. The computer has PCMCIA GPIB card on it. This computer is part of the Device/Instrument which will have GPIB interface. We have 'NI-Device Std. for Windows' for Device application development from NI and 'NI 488.2 for Windows' for the PCMCIA-GPIB card. I installed both of the above drivers and verified the installation. They look fine. But When I run the example application (provided with the NI-Device) 'SimpleGpibDevice.exe' the status code 'NIDEVICE_STATUS_HARDWARE_NOT_FOUND' is returned. I debugged the application and found that 'EnableInterface' method in CGpibDevice class is failing with the above return code.
Does anyone know, What am I missing in the setup/configuration, w
hich may cause that error?
Any help on the NI-Device setup and test would be really appreciated.
Thanks in advance!
Sanjay

Thanks for your response, GPIB Guru!
You are right on #1. I got to know yesterday. I have already uninstalled the NI 488.2 driver. Originally, we were trying PC104-GPIB card with WinNT 4.0. then, we were mistakenly informed that PCMCIA-GPIB works with NI-Device, which you correctly pointed out in #2.
If you find any company or individual who already has NI-Device driver for PC104-GPIB or PCMCIA-GPIB, please post it immediately.
Thanks Again.

How do I create Labview VISA ports for *individual* GPIB instruments using Prologix USB GPIB controller?

Hello,
I'm trying to use a Prologix USB GPIB controller to control GPIB
instruments, and I would like to have a virtual serial (VISA) port for
*each instrument*, as is the case with a normal GPIB controller with a
standard NI driver. However this is not what the Prologix driver
provides -- it provides a single VISA virtual serial port for the
entire controller. To address the instrument with GPIB address 11,
you first send "++addr 11" to the serial port, and then you're talking
to instrument 11. However, this means I have to change all old
Labview programs.
Is it possible to create a "wrapper" function of some kind that will
define a virtual serial (VISA) port for each *instrument* on the
controller? For example, to talk to GPIB instrument 11, call it
ASRL3::11::INSTR, each time it is written to it would have to write to
the virtual serial port of the controller, say ASRL3::INSTR, first "+
+addr 11" and then the command that is sent to it.
A clearer explanation of the difference (i.e. incompatibility), and of
my objective:
1) A normal GPIB controller with NI driver: I go to the NI
Measurement & Instrumentation Panel, under GPIB, and Scan for
Instruments; all the live instruments show up; subsequently when I
want to use Labview programs that use VISA ports, the VISA drop boxes
allow me to choose a different port for each instrument, e.g.
"GPIB0::11::INSTR", "GPIB0::12::INSTR" would be instruments at
addresses GPIB 11 and GPIB 12.
2) The Prologix GPIB controller that plugs into a USB port: In
Labview you get a *single* VISA virtual serial port, ASRL3::INSTR, for
the entire GPIB0 controller. Therefore to address GPIB instrument 11,
you write "++addr 11" to the virtual serial port ASRL3::INSTR, and
then you are communicating with device 11, so you can write and read
ASRL3::INSTR to talk to that device. Then to talk to device GPIB 12,
you write "++addr 12" to the same VISA port, and then you are talking
to that device. The problem is that this requires recoding all
Labview code, whereas I would like to be able to use the same program
either with a normal or with a Prologix GPIB controller. Therefore, I
would like to create code that scans the controller for all GPIB
attached devices and creates VISA ports for all. Such ports, when
written to, would have to first write "++addr DEVICENUM" to
ASRL3::INSTR (i.e. the port of the GPIB-USB controller) where
DEVICENUM is the GPIB address of the instrument corresponding to that
port, and then would have to do a write or read or whatever function
is being done on that instrument VISA port.
I haven't figured out if it is possible to do this easily. Help and
pointers on where to look for hints would be much appreciated. Many
thanks!
Milos

My first impression is that if you don't want to make any changes at all to existing programs is that the wrapper you need is one around VISA. You would need to intercept all of the calls into the NI VISA driver. If you create your own visa32.dll and in there, change the addressing and then call the real VISA driver, you might (repeat, might) get something to work. If this would even work, you still might find that you have to make significant changes anyway. The serial connection is going to be considerably slower, and interface specific functions such as service request handling, bus triggering of multiple instruments, etc., would be difficult to impossible. This would be a lot of work, imho, to just save a couple of hundred dollars over a real GPIB controller. I've seen this Prologix device before and have even used NI's RS-232->GPIB controller. The Prologix intended use to me seems to me more for a hobbyist or very casual user. Of course, I'm used to having multiple GPIB instruments worth 10s/100s of thousands of dollars and the cost of an fully compliant GPIB controller is just lost in the noise.

How to configure the GPIB controller in LABVIEW or MAX to send UNLISTEN and UNTALK when each message ends?

In a PC to PC GPIB configuration, one PC is used as a non-controller and it reads either LACS or TACS status bits continuously. It apears that the controller PC does not send UNTALK and UNLISTEN at the end of each message. The non-controller reads and writes therefor times-out.
What is the correct message synchronisation for a non-controller?
I use Labview 6, PCIIA, WIN98SE.
Thanks.

Are you using LabVIEW as the controller, non-controller, or both?
NI-488.2 does have a configuration option to enable unaddressing. I am not sure of where it is in LabVIEW, but if you search for unaddressing, you should find some information on it. With unaddressing, NI-488. will unaddress the device after communicating with it.
If you are not using LabVIEW as the non-controller, National Instruments does have a software package called NI-Device that may help. This is an API designed for non-controllers. It does not currently have a LabVIEW interface. It works under C++ with a PCI-GPIB board.
A third option is to rewrite your device application. Your device should really not care about TACS or LACS as you read them from the status register Your device
should only look for LACS, DCAS, and perhaps DTAS (if you desire triggering). When it is LACS, it should read data. After a read has completed, it should interpret the data and get ready for a response. It is only at that moment that the device should look for TACS (and DCAS). It is hard to put a flowchart here, but if you design the flow of a standard instrument, you will see some patterns about when to look for certain status bits.

Enet100 GPIB controller on 64 bit OS

After having to upgrade to the new LabView because of a bug and seeing how poor its performance is, I decided to give it the benifit of the doubt and got a brand new Core 2 3GHz PC w/ 8G of RAM.   I figured the time I am wasting trying to use the new interface will pay for the PC.   I now have XP-Pro-64 bit installed to take advantage of the memory, plus most of the tools I use have 64-bit versions now.
I went to install Labview and there appears to be no support for the Enet100 GPIB controller. This is how I talk to most of the test equipment. I know, your thinking why is he not using ethernet. Some of the equipment doesn't support it, and some of the even newest equipment, like the Tek AWG7102 arbs software is so poor that the GPIB is actually a faster way to talk to it.
Any idea when and/or if there will ever be new drivers to support the Enet100 on the newer 64-bit OSs?

Thanks for your help!
I had been looking on:
http://zone.ni.com/devzone/cda/tut/p/id/6893
and noticed:
National Instruments Products XP x86 (32-bit) Vista x86 (32-bit) Vista x64 GPIB-ENET firmware A.5
Assumed because there were no checks for it under Vista x64 there would be no driver.   I downloaded the drivers you linked to and they appear to work with XP Pro 64-bit even though there is no mention of this particular OS.   Tried a few things with the new PC and  LabView is still a little sluggish on it compared to 6.1 on a much slower PC. But it at least shoud require less hair pulling....
If I could just get NI to put the menus back to the way thay have been since the beginning of time and and allow me to do some sort of setup on that control menu so it does not pop up with that stupid express menu that I never seem to use.   If it were even smart enough to use the last setup I had it would go a long way to improve it. Or, even better, give me back the old menus so I can find things faster...

Is there example code for using Ni488 and PCI-GPIB card in non controller mode?

Is there example code for using Ni488 and PCI-GPIB card in non controller mode?

cymrieg,
Your code looks good to me. What is the problem? What happens when it fails? What is the IBSTA value on the controller, and at what point in the code does it stop? What is the IBSTA value on the slave, and at what point does it stop?
One thing is that you might not want to call IBCLR() in a loop on the device. At the beginning of the program is fine...This will send a clear command to the device and will clear out any LACS and TACS bits that might be set. Also your IBDEV call shouldn't be in a loop.
Hope this helps, but let me know if you need more information.
Scott B.
GPIB Software
National Instruments

Command requires GPIB Controller to be Controller in Charge

I downloaded the labview driver HP428XA, the 'getting started.vi' works fine, but all other example application vi's keep giving me the following warning:
'Warning 1 occurred at VISA Read in HP428XA Fetch.vi->HP428XA Frequency Step Measurement .vi. Possible reasons:
LabVIEW: An input parameter is invalid.
or
NI-488: Command requires GPIB Controller to be Controller in Charge.'
I am a novice when it comes to labview, can anyone offer a solution?
thanks!

Hi,
The two error descriptions refer to the fact that the error code (1) has a different meaning depending on what software component gave the error: labVIEW or GPIB (NI-488.2).
Since you are able to use the Getting started VI, that means that the GPIB bus, driver and the VISA library are working porperly. Additionally, you would not get a Controller in Charge error if do not explicitly configure the board to be non system controller. labVIEW automatically configures the board to be controller.
So the error must refer to an incorrect parameter to some LabVIEW function. Open the HP428XA Frequency Step Measurement.vi and use the highlight execution tool to see where the error is generated.
I couldn't find the instrument driver at www.ni.com/idne
t, so I didn't take a look at the driver.
DiegoF
National Instruments.

Command requires GPIB Controller to be Controller in Charge on dequeue element

I have some funky stuff going on in the attached VI. What the VI does is simply to log data to a text file. It is built up as a state machine. This VI's Create state is called from a mainVI (with the help of named queues). I get more than one error and it seems completely random.The error usually occurs if I stop the mainVI, then starts it again. So the second (or following) times the DP VI is called, I get random errors such as the two below:
Error 1 occurred at Dequeue Element in DP.vi->PSS.vi
Possible reason(s):
LabVIEW: An input parameter is invalid.
NI-488: Command requires GPIB Controller to be Controller in Charge.
Error 1 occurred at Close File in DP.vi->PSS.vi
Possible reason(s):
LabVIEW: An input parameter is invalid.
NI-488: Command requires GPIB Controller to be Controller in Charge.
Why is this? I don't even have a GPIB controller?
Solved!
Go to Solution.
Attachments:
DP.vi ‏61 KB

Siniz wrote:
blawson, I think you found the error!
So shift registers only gets uninitialized again if I close the actual VI, and not when I start executing it again? So in reality, they actually behave like real shift registers? I found two solutions to this problem.
1) To initialize the error shift register with an empty error constant.
2) To remove the wire from the shift register to the Write to Text File. This works since I always call the Create state first.
Which one would you recommend?
Also, what is the reason to keep the typedef strict? I have seen non-strict in other code.
Generally you should always explicitly initialize your shift registers unless you want to retain the values from one execution to the next. This is required for Action Engines but in most other cases you should use initialized shift registers to avoid side effects like you encountered in this application.
Mark Yedinak
"Does anyone know where the love of God goes when the waves turn the minutes to hours?"
Wreck of the Edmund Fitzgerald - Gordon Lightfoot

Labview error GPIB controller not adressed correctly

I get this Labview error: GPIB controller not adressed correctly (LV5.1, win NT4) when i try to send data to a HP4275A LCR meter. How ever it works on an older system running with LabView 5.0 (also NT)!!!
How can I get rid of this problem????

Hi Diego, thanks for the hints!
I tried to configure (GPIB) everything standard.
when I try a 488 command initialze, I get the controller conflict, when i don't do this I get atime out problem either by 488 write-command or by 488.2 send-command.
the differences between the systems where it works and where not are:
working: Win 95, LV 5.0, GPIB-card/TNT (plug & play)
not-working: WinNT, LV 5.1, GPIB-card/PCI
i tried to set baord config to the same parameters...
on the faulti system however I see the instrument with the MAX and I can send commands, without problems !!!!
Also the driver you posted does not work (but the NI-communicate program ;-)
i have no clue what else to do!
btw. how do I copy the spy output when running the program? I may provide
this to find errors.
Since MAX indicates the board is all right I guess it is not necessary to reinstall the boarddrivers?!

Embedded systems (PIC based): We are looking to upgrade our GPIB controller chip from Ines iGPIB7210 to a more "mainstream" chip and are interested in NI's offerings.

Ines provides a library of ANSI C source to drive their GPIB chip from any suitable processor (as do ComputerBoards). Do NI have a source code library for their driver chips? BTW it doesn't need GPIB "Controller" capability. The uP controlling the GPIB chip is a Microchip PIC18C452.

Hi Mr James,
Thanks for your question ..We are also planning to have GPIB interface for our equipment .Again we are new to the interface design .For our equipment we dont need controller capability.I think Ni TNT 488.2 T/L is suitable for our application .But we are stuck with this ...Our equipment has a PIC 16c77 MCU.
If you can help regarding the procedures to be followed for having this GPIB interface that will be great!!!
I have some doubts regarding this.
1. How we can use the TNT 488.2 chip in our equipment board.
2. How we can controll this GPIB chip Is it is done by PIC controller?
3. Is above PIC is compatible with TNT 488.2 T/L.
4.Do we need to program the GPIB chip.I know that there is a devoper kit ESP-488 package is there .How we can
develop program for GPIB using this package.
5. Who will help in designing the same
Please help me .
Thanks in advance.
regards
Prasad

Sometimes GPIB controller did not command the instrument to talk while the high-level program did have "READ" command.

GPIB controller should send "UNL", "LA0", "TAxx" to command the instrument to talk. Though the program do have the "READ?" query, sometimes GPIB controller didn't send the above commands from NI Spy, resulting in the system is hanging there. It happens randomly.

HI,
It is not clear to me what is going on. I'd like to get more information.
Could you specify what programming language are you using?. Also, what functions are you using?. What driver version are you using?.
Include any information you think might be helpful. Also, attach the Spy capture.
DiegoF.

Gpib controller enquiry(gpib guru)

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