Using SCPI command in labview

Hi.
I've found an instrument driver for keithley 6221 on keithley.com.
Here is a question: I wana to control this model directly by using SCPI command instead of instrument driver. But, I don't know how can I do this in Labview 8.0.
Tnx.

An instrument driver written in Labview, is not the same as a instrument driver used by say Windows. A Labview instrument driver uses standard Labview functions to send SCPI commands to the instrument. You can learn a lot about the instrument by looking into the Labview instrument driver, and how it sends the commands to the instrument. But having the instrument programming manual at hands is also important.
Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)

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Using SQLplus command in LabView Database toolkit

Hi ,
I would like to ask something but before that this is my set up background
OS : Win 7,
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I have successfully connected with Oracle database using Labview Database toolkit.
The problem now is since I need to query the data from the database,
it will takes time for the labview to process it (since there is so much data in a specific table),
let say that the table in database is "Serial Number", and the data that I want from that table is "SN123"
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(Refer to attachment)
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I wonder if there is a way to put this command on labview database so it will be faster to retrieve the data.
Attachments:
Database.png ‏84 KB

An instrument driver written in Labview, is not the same as a instrument driver used by say Windows. A Labview instrument driver uses standard Labview functions to send SCPI commands to the instrument. You can learn a lot about the instrument by looking into the Labview instrument driver, and how it sends the commands to the instrument. But having the instrument programming manual at hands is also important.
Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)

How do I correctly time while loops using SCPI and VISA/Ethernet communication to send DC current Values to a Power supply?

I'm rather new to using labview and I having an
issue with a test Data Aquisition lab I'm trying to setup using a
Keithley 6221 AC/DC current source and a basic PCI M-series NI-DAQmx.
First of all, I'm looking to update the current value on a power
supply at a rate of atleast 10Hz and I'm using SCPI commands and VISA
communication through ethernet to do so. Attached below is the VI I
have written.
The issue I'm having is this:
My VI will
loop through the values fine in software, or so it seems. I am unable
to get the Power supply to update sequentially if I don't set my loop
delay to anything greater than 130ms. If I try to run the loop faster
it starts skipping values instead of counting 1,2,3,4,5,1,2,...etc. it
goes 1,2,4,5,2,4,1,2 on the display of the power supply and my DAQ unit
also skips these values so I know that the number just isn't getting
read to the Power supply in time. I was wondering if this was due to
my sloppy programming or if it is a hardware issue, my computer or the
method of communication to the power supply? Is this due to the fact
that I'm using ethernet and VISA communication? Is there a faster way
to communicate or is GPIB faster? Any input at all would be extremely
helpful.
On a side note: Right now I'm using an pre-determined
array of values that I can update on the fly but in the future this
with be put into a closed-loop control system. The value for the
power supply output will be determined by the loop and sent that way.
Attachments:
basic DC loop 6221 Keithley.vi ‏145 KB

Also, one of the string constants is NOT set to '\' Codes Display. Here is an alternative method of calculating the index. I removed the DAQ and VISA stuff since I could not run it.
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Attachments:
basic DC loop 6221 Keithley.2.vi ‏16 KB

Does LabWindows/CVI: IVI Instrument Driver Development Course contain subject like Communicating with Instruments(SCPI commands)

HI, I am having query regarding; Does LabWindows/CVI: IVI Instrument Driver Development Course contain subject like Communicating with Instruments(SCPI commands)
LabVIEW: LabVIEW Instrument Control Course Day 1 coves subject like Communicating with Instruments This lesson describes how you can use LabVIEW tocommunicate with instruments. You will learn how touse NI-VISA, NI Spy, SCPI commands, and theInstrument I/O Assistant to perform instrument I/O. My question is to you,Does LabWindows/CVI: IVI Instrument Driver Development Course covers similar kind of training like Communication with Instruments? I am more interested in learning How to use SCPI commands to perform instrument I/O. Will you please guide me? So I can choose correct training course. Thanks & Regards,Jay +91 90110 62790EXFO Electro Optical Engineering India Pvt. Ltd.701, 7th floor The Ceribrum IT Park,Kalyani nagar. Wadgaown Sheri India, Maharashtra, Pune 411014

stick to the original thread.

Changing SCPI commands

Hello,
I am currently using SCPI commands to control my instrument (Agilent 8714ES VNA), making use of the Instrument I/O Assistant in LV.
At the moment, I can tell my instrument to output a given power (say -30dBm) by entering the command "SOUR: POW:IMM:AMPL -30" into the ASCII representation window.
However, I would like to be able to tell it to output a certain power based on the result of a calculation done in LabVIEW. Is there any way of feeding the Instrument I/O assistant with a 64-bit double "wire" to control a given instrument parameter? Is there another way of doing this?
Thanks,
Dan
Message Edited by DanB83 on 10-23-2007 04:44 AM

Use format to string with the string formater as "SOUR: POW:IMM:AMPL %d" and pass the dB as in int to the input terminal then pass this string to VISA write. The visa write will also take a session and error io.
Paul
Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA

"How can i control the instrument with SCPI command by Borland C++ v3.1 using RS232 port"

"hi....
I've ever controlled some instrument by GPIB interface using Labview 6.0...it's really easy to implement .....but the problem is that i hvae to control those instrument under the pure DOS environment now ..so i have to abandon the using of GPIB interface and Labview ....then i choose the RS232 interface with programing the Borland C++ v3.1 and sending the SCPI command by bioscom()....but it got no response at all......so i am wonder if i can control those instrument by using RS232 interface and Borland C++ v3.1 to implement a pure Dos program????if yse,how can i do and is there any sample can be refer to ????
thank you for you help"

Hello Alvin-
We do not have any sample code for programming RS 232 in C on our website. However, you may want to looks at these links for general troubleshooting tips for serial:
Serial Communication Starting Point
How to Do a Serial Loopback Test
Regards,
Ray Kong
NI Applications Engineer

Controling wheelchair by speech command using Neuron Network in labview

Hi all,
I'm doing project about "controling wheelchair by speech command using neuron network in labview". I found some informations about controling whelchair combine with function microsoft speech recognition in window or something like that but this was not my point. So, I have some question about that:
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Greetings;
First, it is most excellent that you have gotten to where you can compare the words being said to the sample.
If I understand correctly, you are interested in continuously acquiring sound, saving it and then comparing it with the sample? That is not as straightforward as it sounds simply because it would be difficult to realize when there is sound in the first place and when that sound is relevant.
I would probably start by figuring out whether there is or not sound by comparing the microphone input to a certain threshold, saving if there is sound, and then halting the recording when the sound stops. It would be then that you would compare with your samples via the algorithm that you have made.
In order to check for volume, I came across the following example:
http://zone.ni.com/devzone/cda/epd/p/id/2150
It was mentioned in the following discussion:
http://forums.ni.com/t5/LabVIEW/Microphone-Input-Detection/td-p/487367
Cordially;
Simon P.
National Instruments
Applications Engineer

I'm new to the LabView. How do I pass data from VI configured using Serial (CMTS using CLI commands to set Parameters ) to VI configured using GPIB(vector signal analyzer ) to measure such as RF frequency or power on the instrument? Thanks

I'm new to the LabView. How do I pass data from VI configured using Serial (CMTS using CLI commands to set Parameters ) to VI configured using GPIB(vector signal analyzer ) to measure such as RF frequency or power on the instrument?
I just want to set something on the front panel that will execute the Serial parameters first and then pass these settings to vector signal analyzer
Thanks
Phong

You transfer data with wires.
Frankly, I'm a little confused by your question. I can't think of any reason why you would want to pass serial parameters (i.e. baud rate, parity) to a GPIB instrument. Please explain with further detail and attach the code.

Need example vi using AT commands for dialing the modem at the remote end

Can any one give example vi for dialing up a modem and sending data to remote end

Hi sindhu6,
Presuming that you are connected to your modem via a serial connection:
I did find a forum related to your enquiry: http://forums.ni.com/t5/LabVIEW/AT-commands-in-labview/td-p/1213335
And I did find an example from ni.com: http://zone.ni.com/devzone/cda/epd/p/id/2577
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Learning new things everyday...

SCPI command to set the frequency for power measurement on Agilent 53147A?

Hello,
I am trying to automate some measurements which require me to use an Agilent 53147A Freq Counter/Power Meter/Digital Voltmeter. The instrument has an option of setting the frequency of the signal we intend to measure. This is done by clicking the "FREQ" button on the instrument and entering the frequency value of the signal whose power we intend to measure. This way the power meter uses the appropriate calibration factor for that frequency for providing accurate signal power level.
I have been trying to set the frequency of the signal whose power I intend to measure through remote control but have not met success as I have not been able to find the SCPI command associated with this task in the operating manual. Does anyone know what SCPI command is to be used for this purpose? Any comment in this regard is highly appreciated.
Thank You,
Vivek

Hi vivek.madhavan.13,
Try using the drivers for this device found here:
http://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=834204A36619504AE04400144FB7D2...
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National Instruments

Problem: Using "msg" command with "System Exec.vi"

I'm attempting to write some LabView code that takes advantage of the "System Exec.vi". At the moment, I've tried using it to ping machines, return the ipconfig and run through the example code that NI provides.
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msg.exe /server:localhost * test
When I launch the batch from windows, it executes. When I launch it from LabView (using the System Exec.vi) it fails.
Potential Quirks:
I discovered in a different location that in order for a machine to receive these messages they need to have a registry entry in:
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Note that "/server:localhost" could be "/server:anycomputer" and the " * " is used as a wildcard which sends a message to anyone who is logged onto that machine. Also note that "test" is the message to be sent.
Any ideas why I'm having a problem?
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- Mike
~~~~~~~~~~~~~~
Current Setup:
LabView 2010
Windows 7
Solved!
Go to Solution.

-> What versions of labview and windows are you on?
LabView 2010 and Windows 7.
-> Have you ever sent any commands out, or is msg the only one you've tried so far?
I've successfully used the 'ping' command and also returned a standard 'help' command to LabView.
-> Finally, in tools>>options, you may need to change your access settings under VIserver and Webserver.
My VI server settings are allowing everything except "Show VI Scripting Functions, properties and methods"
I have nothing configured for a web server, since I didn't plan on using it for this. Unless it has some sort of connection that I am missing.
I'm attempting a work-around where LabView will generate a batch file to run from the desktop instead, since it seems that something is getting lost in translation between LabView and the command-prompt.
- Mike
~~~~~~~~~~~~~~
Current Setup:
LabView 2010
Windows 7

Goto command in LabVIEW

Hi
I was wondering if there's anything like a "goto" command in labview. For example, if I am in a for loop (and the for loop hasn't reached it's number of time to loop yet) and need to exit the loop and jump to somewhere else in a code because I encounter some error condition. I know I can use a while loop for this if there isn't any goto command, but that's my last choice because it's kinda complicated for a nested loop with many procedures.
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I too would like to find a way to mimic a "goto" function.
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Run ssh command in labview

does anyone knows how to run an ssh command in labview?
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thks
JP

Unfortunetly, I don't know how to script in a password for ssh. SSH closes the stdin and re-opens the tty that you are logged in at. This is actually a security feature. As well as a way to send stdin to remote programs (otherwise your password would get in the way.)
If you don't need to ssh to a remote host, and you want to chmod something on the localhost, you could use sudo instead. With sudo you can specify certain users (or all users) to run certain commands. (so you could make a shell script to chmod for you).
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May I ask why you want to chmod something on a remote system that requires root? Sounds like maybe you should create a LabVIEW application on the remote side that acts as a daemon (running as root) and accepts connections and commands and does the chmodding for you.
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NI-VISA driver wizard and SCPI command

Hi,
I had a go with a NI-VISA driver wizard. I wanted to create a driver for MH3114 DAQ. Wizard went trough very smoothly, and the driver has been installed.
However when I did *IDN? under MAX I've received an error.
Does it mean I have to create/implement any SCPI command?
How the wizard is intened to work?
Solved!
Go to Solution.

Hi MimiKL,
As Dennis has said, instruments are either designed to work with SCPI commands or not. If the user manual does not state the device is SCPI compliant then SCPI commands aren't going to work.
All the driver wizard does is generate a number of VIs which will send the standard SCPI commands to an SCPI compliant instrument. Depending on how you are communicating with the instrument (which bus) you may need to modify these VIs subtly to work with different instruments. But, as mentioned, if the device you are trying to communicate with isn't SCPI compliant then this is never going to work. For future reference, when using the driver wizard, all of the generated subVIs will have comments in them telling you exactly what you need to replace and change to get the driver working for your instrument.
If your device isn't SCPI compliant and you have a dll which works then you should continue using it.
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National Instruments - Tech Support

How to send SCPI commands to a VXI instrument

I am using a VXI Interface tech SR2510 LVDS card with teststand and keep getting the following error when the intial diagnostics test trys to run. "Device I/O Driver error" I tried to use the Visa Interface and the interactive control in NI MAX but was not able to send SCPI commands. What can I use to communicate with this card. The resource manager does successfully execute and I see my instrument in the devices list so I am confident it is not a VXI problem.

Hello DF1963,
Can you communicate with the card through its driver/interface? Also, please review the following NI-VISA Help topic: Introduction to Programming VXI Devices in VISA to ensure that correct commands are being sent. If your device is correctly configured in MAX, I would also recommend verifying with the card manufacturer as well.
Best regards,
Ali M
Applications Engineer
National Instruments
www.ni.com/support

Using SCPI command in labview

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