Acquiring CONSECUTIVE signals with Signal Express

How can I record multiple signals consecutively in Signal Express using the same input device and the same DAQ channel? It seems to me that even if I have separate execution loops, the program will still try to run all the acquisitions at the same time through the same channel. ..and I'll get an error. I've tried one exceution loop and I can't the program to do this ..even when I have the 'run after previous step' box checked. Any help would be much appreciated.

Hello Sound Tech
You do not have to put another step inorder to acquire multiple channel. In the first DAQmx Acquire step you can select multiple lines by pressing Ctrl and configure your timing and you will be all set.
Thanks
nAyer

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Acquire 2 signals with different sampling rate?

Hello,
i am using first time labview signal express together with a NI pci 6251 & NI Scc 68 device.
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When I try to acquire them I couldn't figure out how to set the sampling rate for each signal, only for all signals.
When I created two DAQmx assistant acquire tabs. An error occurs always: "the specified resource is reserved".
So my question is is it possible to do this?

hello markus_umd,
no, it is not possible to create different samplingrates for individual channels on one daq device.
if you want to record one channel slower, you must reduce the samples for that channel in your program.
if the channels have a common divisor, you could implement your task. you find more information here:
Sampling Different Channels at Different Rates with NI-DAQmx
kind regards,
robert h
NI germany

Interface to HP34970A with Signal Express

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I am trying to interface an Agilent HP 34970A using a demo version of Signal Express 1.2. I installed the ivi-com driver version 1.0.0.4 from Agilent. When I go through "add step/IVI DMM Acquire" there is no instrument driver available in the pull down menu. Is there something I should do in MAX ? I have the same issue with a scope TDS 7104 using Tektronix ivi driver 2.5.
Thanks for your help.
Rob

Rob,
Thank you for contacting National Instruments.
It sounds like there is a problem with the installation of the instrument drivers. There is a knowledgebase that walks you through the installation of IVI drivers with SignalExpress. Also National Instruments provides instrument drivers for Tektronix TDS 7104 and Agilent Technologies 34970A.
The drivers that you have currently installed should work, but the National Instruments instrument drivers for the two devices could be more likely to install properly. Also please step through the associated knowledgebase.
I hope this helps. Please let me know if you still are having the same issue. Have a great day!
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Thanks
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DustDevil,
First, welcome to our forums!
Second, we have a great KnowledgeBase article here that talks about the various timing settings you have available and what they each will mean for the timing of your measurements. In that article, "number of samples per channel" corresponds to the "samples to read" you have available in SignalExpress.
Also, the 9227 is one of our modules that uses Delta-Sigma modulation to get a higher resolution, which has some caveats as far as sampling rate is concerned. There is a minimum data rate (about 1600 samples per second) that you cannot sample below. If you set a rate lower than 1600 you'll still be getting data back at 1600 S/s. This help file describes the "Subset and Resample" step you can use in SignalExpress so you can acquire data at the minimum rate of the device and then resample the result to end up with data at the "rate" you actually want.
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Why the acquisition with DAQmx is different by using Labview 8.2 from Labview signal express?

Hello,
I am using a PCi-6281 to acquire a voltage. When I am using Labview signal express with only the step to acquire I read the good signal with the exact voltage. But when I am using my VI, the y axis and the values recorded are wrong. Why this difference appears?
I insert a picture with both signal: at the top is the signal from my vi (wrong measurement) and at the bottom is the signal from labview signal express (correct).
The vi I am using is the example Cont Acqu&Graph Voltage-To file (binary).vi.
Thank you for your answer!
Sophie
Sophie

I am using the binary file because it requires the minimum change in another VI. I have tried to change in scaled data but now my second VI has not enough memory to display all data.... What's wrong? Here is my second VI. Totest with data you need to insert a number in the "scaling factor" if not the dat are multiplied by zero...
thanks for your help!
Message Edité par stage84 le 07-24-2009 10:11 AM
Attachments:
Display 3.vi ‏1867 KB

Synchronise NI 9239 & NI USB 8473 with Signal express

Hello, I have a Cdaq 9174 chassis with an NI 9239 module (analogue input at 50Khz/ch) with Signal Express.
And I wanted to know if we could acquire this four inputs synchronised with datas from CAN connection by using a NI USB 8473 ?
Many thanks.
Patrick.

For me you can't use the driver NI-CAN is not compatible with Signal Express. The Only way you could use it with SE, is to pass through LabVIEW VI.
You'll find in the below link the way to do it.
http://digital.ni.com/public.nsf/allkb/359D14941D6936E98625729D008387D5
I advise you to stay in LabVIEW this kind of program. It's easier.
Best regards.
Sabri JATLAOUI - Certified LabVIEW Developer

How to synchronize the signal sending and data acquiring process dynamically with one DAQ_Urgent

Dear Sir,
I am using one DAQ card to send a modulation signal (which is a signal summed by a low frequency saw tooth and high frequency sin signal) to the laser controller, and acquire voltage signal from another instrument (It is in a same measurement system with the laser controller)?
I would like these two process happening at the same time.
In the attachment, there are two parts, one of them is signal generating program, the other one is data acquiring program, how to do like this: when I press"run", first the modulation will be sent to the laser controller immediately, and at the same time, the acquiring program starts as well...
In addition, I think my program is not complete, could you please help me check if there are any other problems with it?
Thank you very much.. and appreciate your quick reply in advance.
Best regards,
Memorysun
Attachments:
Signals generation and lockin recording.vi ‏1227 KB

Jamie S. wrote:
Hi Memorysun,
Thank you for your post and welcome to the forums.
From your description what you want to achieve is:
Write data to a Analog Output channel that is then recieved by the Laser
Acquire (read) data from using an Analog Input channel (output from Laser/Instrument)
This can be achieved using a single VI with 2 seperate DAQ tasks, one the "Continuously Writes" to the Laser and the other that "Continuously Reads" from the Laser/Instrument. Can I recommend the following examples that can be found in the NI Example Finder (Help>>Find Examples>>Hardware Input and Output>>DAQmx):
"Cont Gen Voltage Wfm-Int Clk.vi" (for continuous writing)
"Cont Acq&Graph Voltage-Int Clk.vi" (for continuous acquisition)
The code from within both these VI's can be placed in a single VI therefore achieving the desired functionality.
Many Thanks
Jamie,
They would be better served with an example that routes the AO hardware sample clock to the source of an externally clocked AI.
Using the examples you posted will still leave them with the challenge of trying to alligh stimulus with response.
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

Acquire a signal with mac osX

Hello.
I am a very beginner with LabView.
I would like to acquire a signal with a NI-USB 6009. I have LabView 10 on osX 10.8. I already installed the daqmx base driver.
Could you explain me how to acquire a signal which come from the NI USB 6009 and export it as a list of numbers (the amplitude and the time).
Thanks!

Hello matttgic,
What kind of signal do you want to acquire/generate?
For exemple, if you want to acquire an analog input, you should use the architecture use in the file "Analog_input attach to this email.
As Johnsold told you, you can find some code for your device in the "find exemple" section of LabVIEW.
Hope this help
Sabri
Attachments:
Analog_input.PNG ‏13 KB

I PXI 1010 with Digital Osci, RIO cards. Any simple projects to illustrate PXI with Signal Express and/or using Digital Osc.?

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regards,
Brian

Signal Express not activated with Labview Full Development System Volume License

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LabVIEW Full Development licenses still include Signal Express. Are you saying that whenever you are connected to the server you can run Signal Express just fine, but whenever you create a disconnected license Signal Express is not able to launch? Can you verify that you are, in fact, checking a license out from the server whenever you are connected to the network?
If you still have trouble I would recommend calling NI support so we could get more informatioin (such as your license file, contract ID, etc).

Operating Signal Express with Labview 7.1

Hey,
I have just recently installed Signal Express as a portion of the Sound & Vibration Measurement Suite and teh Sound & Measurement Assistant front end works well. When I attempt to start a new VI in Labview 7.1, I am unable to insert tools from the order analysis menu.
Do I need to upgrade Labview or is there another solution
Thanks
Doug

Hello Doug.
Thank you for contacting National Instruments.
The readme of Sound and Vibration Measurement Suite 5.0 states that you must have LabVIEW 8.2 or later Full Development System or Professional Development System installed and properly licensed in order to run this application successfully. So, I hate to be the bearer of bad news, but it appears that you will not be able to use this Measurement Suite inside of LabVIEW 7.1. As further confirmation of this, do you see any S&V or Order Analysis VI's on your functions palette in LabVIEW? If you don't, this will indicate that the functionality for LabVIEW was not installed because of an incompatibility between the toolkit and the version of LabVIEW.
Let me know if I have explained this well. If there is anything else I can do for you to help you through this, please let me know. I will be more than happy to help!
Brian F
Applications Engineer
National Instruments

IPad and iPhone 4 and new 5s drop connection with airport express. This just started recently after working fine for a year. PC does not drop. Wifi signal fine. Help?

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What does any of this have to do with the Apple TV?

Accessing digital inputs from signal express (TEK MSO2024)

Hi,
i'm trying to access the digital inputs of an TEK MSO2024 from signal express, but no luck.
I'm using SignalExpress2011, tkpdo2 ivi driver.
Seems like this driver doesn't support digital input, anyone got a solution or another driver?
*edit
topic can be deleted
on another system DI works...
Regards
alex

Hello,
The best to way drive digital outputs while acquiring analog inputs is to create two steps in Signal Express. Each step will execute relatively at the same time but there is no way to correlate or synchronize DIO with AI on a 6008 because DIO on that device is software timed while AI is hardware timed. Below is the 'Getting Started with Signal Express' manual which can aid in creating an AI and DIO step. Also, if you need additional examples later, they are located in the Help->Open Examples.
Getting Started with LabVIEW SignalExpress
http://www.ni.com/pdf/manuals/373873e.pdf
Regards,
Patricia B.
National Instruments
Applications Engineer

Labview Signal Express and Matlab

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I am using Labview Signal Express to acquire and log data from an injection moulding machine (with NI USB-6218).
The logs contain more than 65000 samples so my boss told me to treat the data with Matlab.
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Regards.
Helene

Hi there, I’m currently studying mechatronics in Sligo institute of Technology in Ireland and we have to do a SCADA project using LabVIEW to control an injection moulding process. I work in the Water and waste water treatment area so I’ve no experience of Injection Moulding. I found your address on the web and was wondering would you have any screen shots of what an injection moulding SCADA interface would look like or a schematic/P&ID of an injection moulding process. Any help would be greatly appreciated. Regards Richard Crowe

Adding offset to LabView Signal Express signals

We are using a USB 6535 with LabView Signal Express.
The logging need is to record 8 channels of data, with each having 3 unique (0->5V) signals.
So far, only the first channel has been wired in an the logging inputs set up.
With a standard scope, there are offsets to offset a signal vertically, and to thus see the overall time relationship.
How is that done with LabView Signal Express?
Each channel's 3 signals need to be grouped together and then 8 channels vertically offset for visibility.
Thanks

Hello,
The best way I can think of is to create a constant signal (or however many you'd need) and add or subtract to the signals you are acquiring. In SignalExpress, there's an Arithmetic step that is helpful for this. The following KnowledgeBase article from our website offesr one way to do this in SignalExpress:
http://digital.ni.com/public.nsf/allkb/555B4791612E261E8625763F0031DC2C?OpenDocument
Best,
Ryan C.
Applications Engineer
National Instruments

Acquiring CONSECUTIVE signals with Signal Express

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