Instrument Control (GPIB, Serial, VISA, IVI) topics

ibrd() takes too long

James_Hume — Sat, 25 May 2013 13:43:07 GMT

Also posted, in much greater detail (no word limit) at StackOverflow - http://stackoverflow.com/questions/16749913/programming-agilent-counter-gpib-ibrd-takes-too-long

I'm programming an Agilent "Universal Counter" (53132A 225Mhz model) over GPIB using the National Instruments driver and C interface.

I want to measure the Time Interval between two clock signals (1 PPS - pulse per second). I am definitely getting one edge per second. But, my app makes a measurement every 2 seconds and the reason is that fetching the result takes about 1.9 seconds.

My thread loop is to start a measurement (SCPI cmd INIT) and read the result (SCPI cmdFETCH:TINT?). Do this in a tight loop as quickly as possible. Which would easily handle I measurement per second, except reading back the result takes forever (well, 1.9-ish seconds)...

Debug output shows:

SendSCPICmd at 1369486341s
SendSCPIQuery at 1369486341s
SendSCPIQuery: ibwrt() at 1369486341s
SendSCPIQuery: ibrd() at 1369486341s
***SendSCPIQuery: ibrd() took 1994ms***
Result at 1369486343sPosted to queue  at 1369486343s

So, now I know I'm throwing a lot of code down next, but if you have the time an inclination to look, I'd very much appreciate ideas as to why ibrd() in the function SendSCPIQuery() takes such a long time to complete after the FETCH command has been sent? Any ideas appreciated :)

<For code samples please view the stack overflow post (link at top of post, thank you)

Sincronización señal escalon

GuillermoLP — Fri, 24 May 2013 14:10:41 GMT

Hola,

Soy nuevo en el uso de LABView y quisiera pedir ayuda respecto a una modificación que debo hacerle al código adjunto. El problema consiste en que debo enviar una corriente AC de alta frecuencia con un valor determinado durante un tiempo corto (0.1 segundos), posteriormente debo tener un tiempo de ralajación (3 segundos), y así sucesivamente durante un tiempo determinado (del orden de 24h). Es indispensable que se inicie en cero, es decir, 0, Señal, 0, Señal, 0, Señal, etc., para evitar ruido al empezar las medidas. Es indispensable que la señal y el almacenamiento de datos esten sincronizados, así como está el programa ya guarda y grafica los datos, pero no se como implementar esta parte nueva. Si me pueden ayudar les quedo profúndamente agradecido.

GBIP interface

rajavle — Fri, 24 May 2013 09:16:37 GMT

Hai..

This is Rajavel from Finland. We have Keithley 236 and GBIP cable and also labview 2012 vrsion software.

I first installed Lab view then i installed NI max (ni4882_302) verson. Then i download the Keithly 236 drivers.

After installing NII max i go device and system then i double click GPIB+HS 'GPIB0' and the press scan for the instruments and i got GPIB0::14::INSTR. In that i got the IP address (14) and select Labview 2012 version then i click button go.

It go to the labview program now is shows instrument driver finder configure search in that i select the conected instrument and i will show the code of my connected instrument which i got it NI max.if i go that way means i didnt get results in that .

After that i go the installed drivers in that it showed agilent, Keithly 2000, Keithly 24xx and Keithly 27xx after that if i select any one from keithly it shows some simple VI programs but i doestn communicate with my instrument.

So can you solve this issues for me..

Regards

compactRIO + interbus + servo

Alex@GT — Thu, 23 May 2013 15:53:40 GMT

I have a servo drive i am attempting to interface with using a compactRIO-9082. However, the drive uses the interbus protocol an an ethernet RJ-45 cable. What would be the best solution to acquire communication?

thanks!

NI License not available online

Shreenath — Thu, 23 May 2013 14:19:01 GMT

Hi,

The license file for all the NI software is not available online. When we go to download NI-VISA we can see the license.rtf but none of the other downloads like IVI Compliance Package, NI-Scope, NI-Fgen or NI-DMM do not show any license file. Is it possible to host all these license files just like NI-VISA?

Also are all the NI downloads governed by the same license agreement?

Thanks
Shreenath.R

Could a long delay (~30 mins) between the opening of a VISA port and the first Visa Read called on it cause an error?

cgiustini1 — Thu, 23 May 2013 05:53:08 GMT

Hi,

In my application, I am reading data from a VISA device that is communicating with my unit under test. Here is the sequence of events:

-unit under test powered on

-VISA port opened

-wait for trigger

-unit under test powered off

-wait thirty minutes

-unit under test powered on

-continuously read from device with VISA read

-when test ends, VISA port is closed and unit under test is powered off

Sporadically (and usually at the worst possible moment), the first VISA read performed returns an error that ruins the rest of the test. Sometimes it is buffer overrun (error code -1073807252) and today it was I/O error (error code -1073807298). Does anyone know if that thirty minute wait could be causing any problems? They seem to happen more frequently when I run this particular test.

Thanks,

Carlo

scope waveform read error

dhaval.isro — Thu, 23 May 2013 04:39:53 GMT

hello all,

i am connecting Tektronix DPO 7104 scope via RS 232 USB UART connector in LABVIEW.

the labview code runs well upto "initialize" VI without error.

whenever it enters into "fetch wavweform measurement" VI, runs upto "VISA write" block successfully but creates error out after passing from "VISA read" block...the error code is 1073807339,"the error occured at unidentified location". plz give me possible solution..... thanks....

Prologix GPIB LabVIEW error 1073676294

AM33 — Thu, 23 May 2013 03:00:46 GMT

Hello,

I am getting an error code 1073676294 on one of my GPIB read steps. It is a Prologix GPIB. The LabVIEW program is supposed to plot Lock-in voltage in one graph and o-scope voltage in another graph. The setup is for taking piezoelectric measurements using a homodyne laser set up. I have attached the vi in hopes that it may useful to anyone who can help me.

Computer doesn't detect GPIB-RS232

rudrumline — Wed, 22 May 2013 20:36:56 GMT

I have a GPIB-RS232 that's part of a stage controller system. 6 months ago, there were no problems detecting and sending commands to the stage through GPIB, however another coworker of mine has been using the system since then and now when I've tried to use it, the computer cannot communicate with the stage controller. I've looked up help on the GPIB-RS232 and noticed that only the power light is on on my GPIB-RS232 - the RDY light is off. I'm not sure if the problem is the set-up of the computer or something wrong with the GPIB-RS232 unit. Does anyone have any ideas what the problem could be?

Error-1073807253 quick question

mrmani — Wed, 22 May 2013 20:06:32 GMT

Hi,

I am running a monochromator through labview, and when I run it, it starts working fine, but then after a random ammount of time it says: "ERROR-1073807253 at Visa Read. A framing error occurred". What can I do?
Any help is appreciated

How to separate the serial data corresponding to their ID

srajasek — Wed, 22 May 2013 17:17:10 GMT

Hi ,

I have recently started using labview for school and for personal projects. I have couple accelerometers connected to arduino board and I am reading the data serial port using labview. Since I have couple sensor of same kind I have assigned ID to each sensor, so when I read data from each sensor I can recognize which data is from which sensor. Now when I read in serial I am reading the message as shown below (using Labview VISA)

29X:\s12\sY:\s24\sZ:\s-10

83X:\s12\sY:\s24\sZ:\s-10

where 29 and 83 is the decimal value of hex adress 0x1D and 0x53. X:, Y:, Z: are the data from my accelerometer. I would like to look to separate the data corresponding to their device address. Can any one please tell me how I can separate the data corresponding to their device ID please.

Thank you!

ni4882 on openSUSE 12.1-3.1.10-1.19-desktop problem

cwsnyder2001 — Wed, 22 May 2013 17:07:32 GMT

After installing the kernel-source and kernel-syms packages and following the steps in the README.txt for preparing openSUSE for the NI4882 install, the install hangs at the post installation steps. gpibtsw indicates the sodtware is not correctly installed and gpibexplorer suggests running updateNIDrivers. updateNIDrivers stops output and hangs at "pte_offset funtion:"

The niSystemReport output follows:

/usr/local/bin/niSystemReport version 2.3.1f0

********************************************************************************
/bin/uname -a:
Linux vtvax_linux 3.1.10-1.19-desktop #1 SMP PREEMPT Mon Feb 25 10:32:50 UTC 2013 (f0b13a3) x86_64 x86_64 x86_64 GNU/Linux
********************************************************************************

********************************************************************************
/etc/SuSE-release:
openSUSE 12.1 (x86_64)
VERSION = 12.1
CODENAME = Asparagus
********************************************************************************

********************************************************************************
/etc/os-release:
NAME=openSUSE
VERSION = 12.1 (Asparagus)
VERSION_ID="12.1"
PRETTY_NAME="openSUSE 12.1 (Asparagus) (x86_64)"
ID=opensuse
********************************************************************************

Configuring for linux kernel version 3.1.10-1.19-desktop.

********************************* NOTE *********************************
Using kernel headers found in /lib/modules/3.1.10-1.19-desktop/build.
If this does not correspond to the location of the 3.1.10-1.19-desktop headers,
then define KERNELHEADERS in your environment to point to the location
of the kernel headers, define KERNELTARGET as the version of the
kernel for which to compile, and then rerun ./configure.
********************************* NOTE *********************************

Kernel has reparent_to_init(): no
Number of arguments for do_munmap(): 3
pte_offset function: ^C

Help anyone?

Thanks,

Charles

LabView 8.5 and NI-488.2 error: I/O operation aborted (with MI Bridge 6010 and thermometer)

dade145 — Wed, 22 May 2013 09:34:51 GMT

Hi ,

i've got a new issue: using LabView 8.5 and a GPIB-USB-HS connection, NI 488.2 drivers are installed,

I encounter an error such as : NI 488.2 I/O operation aborted (this error drop the running of LabView application found in the example application)

I'm trying to link a 6010 resistance bridge by the Measurements International, which is link to a resistor (known) and an unknown thermometer.

LabView detects MG2000 drivers, but by using the applications built upon it I get different errors such as : Error -1223 occurred at MG2000 Initialize

Can you help me?

Thanks Davide

the differences between two ways to communicatet with rs232

JinHaoren — Wed, 22 May 2013 07:52:59 GMT

There are two different ways to communicate with serial port RS232. I will show as following pictures.

1. The Basic Serial Write and Read. VI.

2. use VISA

So what the differences between these two ways?

Can I also use the method 1 to achieve the functions as shown in method 2?

Thanks

downconvert ivi driver

nisitha — Wed, 22 May 2013 06:13:08 GMT

can u please downconvert ivi driver 9.0 to ivi driver 8.5

which string will write first?

dav2010 — Tue, 21 May 2013 02:29:13 GMT

I'm using serial commands to control motors, and the sequence that the commands are written to the motor controller is important.

In the general structure shown in the attached vi, will "String" will be written 1000 ms before "75"?

Or, will the "75" be written before the 1000 ms WAIT function counts down? Is this structure a good way to control the order that serial commands are written to a device?

THANKS!!!

Can non-data lines in Parallel Port be accessed with VISA?

rocket_author — Mon, 20 May 2013 22:57:20 GMT

Hello all,

Wondering if anyone can confirm or dis-confirm if VISA can access the lines of a parallel port besides D0-D7; if so, how would one go about this?

switching mains operated equipment on and off with NI and Labview

caleythistle — Fri, 17 May 2013 23:23:07 GMT

Hi,

I am looking to monitor and control a custom oven. Is there an NI product can I get that will allow me switch a AC mains device around 5A on and off?

Regards

Richard

How to trigger more GPIB devices via VISA Assert Trigger

pumadace — Fri, 17 May 2013 16:37:38 GMT

Hello,

Im still beginner and Im looking for solution, which I couldn't find anywhere.

I want to synchronize two devices via GPIB but I have agilent 82357B USB to GPIB so Im using only VISA palette (cos GPIB is not working).

My question is if there is something like TriggerList in GPIB 488.2 ? Or could I trigger more than one device with VISA Assert Trigger?

Thanks a lot for your help.

TPC 2012 Which Touch screen controller chip?

Daryl — Fri, 17 May 2013 06:22:58 GMT

Does anyone know which touch screen controller chip NI uses for the 8 wire resistive panel on the TPC-2012?

Thanks in advance