I am working with a PXI-7952R FlexRIO FPGA module in conjunction with the NI 6581 Digital Adapter Module. The DIO lines only get used during certain tests and are idle the rest of the time. By default I have them idle in the Read state. My question is is it better to have them idle in the Read or Write state? Or does it really matter?
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DIO Idle Direction
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user defined sequence
Hello,
I'm looking to create a program in Labview that has the user create a sequence then for labview to play it back.
For example:
There are 5 LEDs.
A simple pattern the user makes is, first LED on for 2 seconds, pause 1 second, 3rd and 4th LED on for 3 seconds.
I'm not sure exactly how to start. Any feedback would be great.
Thanks!
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Problem with PXI-6541 trigger interrupt
Hi,
I have problem with getting trigger on PXI-6541. I have connected Busy line (shown in figure attached, it is used as trigger) on PFI 1 on CB-2162. My application requires that External signal (Figure) should be generated and SDO (Figure) should be acquired on the falling edge of Busy line. External signal is generated from HWS file. The problem is that it is not triggered and I get time out error. My DUT voltage levels are 5V. Also my DUT, when powered on remains in logic 0 till it receives clock(External as shown in figure). Sleep time shown in figure (Busy Line) is 6us.
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Sourcing a 15-pin D-SUB Twisted Pair cable to fit on a NI 9411 C Module
Hi,
I have an NI 9411 that I'd like to connect to and I'm looking for a 15-pin D-SUB Twisted Pair cable.
I have spoken with NI sales and the best they can offer is the following, which is unfortunately not twisted pair:
http://sine.ni.com/nips/cds/view/p/lang/en/nid/212301
They advised that I have a general look around on google/RS Components, which I've done. I've found quite a few straight-through
15-pin D-SUB cables but still can't seem to find one with twisted pairs.
Unfortunately, making my own cable isn't a viable option.
Has anyone ever used a cable like this and know where to buy one in the UK?
Thanks.
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Using Labview to Control Perisaltic Pumps through a USB Control Board
Hi,
I am quite new to Labview, so I apologise if this question is under the wrong category, but what i'm trying to do is to control some 4 lead bi-polar peristaltic pumps in Labview. The pumps are each attached to their own USB control board, and all the USB boards are attached in seriel with one acting as a master and the other 3 as slaves. I have never attempted this before and am trying to do it because the software supplied with the boards already is extermely poor and very buggy. So I have contacted the manufacturer of the boards/pumps asking for assitance since he was the one who suggested to use labview if the software wasnt meeting our needs. The control boards have dip switchs allowing the control to be USB or RS232. I have read around on the forums here and other people have been suggested to use VISA to send code to the pumps to allow them to run. Im using Labview 2014, on Windows 8.1 with the drivers for the USB control boards installed (FTDI virtual COM port). The pumps are UNO boxer 15K pumps and the control boards are the only control boards UNO boxer sells.
Any help at all to get me started would be greatly appreciated.
Regards,
Jonathan
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Ni 9437 always "on"
Hello,
I have a cDaq 9178 with some module. All of my modules works well except one, the NI 9437. it is a module with 8 DI.
When i connect it on my chassis, the Leds of the modules are always on, so when I launch my application on labview, I have always my Inputs on even when I have nothing connected to my module.
Someone know why ?
I installed the last version of the driver, and I use labview 2014.
Thanks a lot.
Mehdi
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Controlling individual channels of NI9481
Hello all. I am controlling a test fixture containing 4 linear actuators. My program has 4 While Loops inside a bigger while loop. Each while loop controls an actuator. There is a cluster control for each actuator allowing the user to enter cycling times. So the user could make actuator one cycle at 1 sec on/1 sec off, actuator 2 at 0.2 sec on/0.5 sec off, and so on. I am using an NI9481 to control the power to the actuators. So when the 9481 engages, the actuators close; disengaging makes them open.
My problem is that the 9481 does not allow me to operate an indivdually channel. If the user puts a long/short cycle time on one actuator, that channel needs to stay active until the cycle time limit is reached. Sometimes the different cycle times may be necessary because of physical wear and tear which causes actuators to start slowing down or speeding up. It does not seem that I can assign a different task to each channel of the 9481 to make each channel operate differently. The timing of each loop (based on what the user inputs) would determine when a channel activates/deactivates. If I could get the 9481 inside of each mini-loop, that would do the job, but that causes a problem with reservations.
Is there a way I can individually control each channel in the 9481?
I have attached the vi for viewing. Please be warned, we have Labview 2010, the company will not upgrade beyond that, and I am self-taught in Labview (and always learning). So if the vi looks horrid, inefficient, and other such things, those are the reasons why.
Thanks for any and all help.
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is it possible to use part of Port0 on a 6363 as line controlled and part as digital wave output?
I've filled the DIO on Port1 and Port2 of a PCIe and need to use port0 for both line controlled (toggle) and digital waveform output. I'm using Measurement Studio 14 and C#. I can make the call:
NITask.DOChannels.CreateChannel("MyMIO/port0/line8:11", "myTask",ChannelLineGrouping.OneChannelForAllLines);
and run the waveform without issue. The problem is that the unselected lines are cleared.
I can kludge around the problem by maintaining the state of all lines on Port0 and accounting for them in the waveform. That is kind of a pain, adds code, and I'm lazy. Is there a way to isolate the wave to only the lines selected when creating the task?
Thanks,
Derek Hopkins,
Pacific Northwest National Laboratory
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Use the NI 9403 as RS232
hello
For measuring a digital signal from a CV7-V wind sensor
which has the following characteristics
how I can use the NI 9403 module as RS232
for example Campbell Scientific CR1000 offers 8 I/O or 4 RS232
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Can I generate digital waveforms for PXI-6541 using c# code?
I have a PXI-6541 which I am using to generate some digital waveforms during my experimental run. I would like to be able to dynamically change some of the waveforms as these control parameters I would like to vary in our experiment (more specifically, I want to vary the pulse length of an analog signal generated by a DDS, which is in turn controlled digitally through the PXI-6541), so I don't think the NI Digital Waveform Editor is the best solution. Is it possible to generate waveforms for this card using the c# DAQmx libraries? I've seen some examples such as tps://decibel.ni.com/content/docs/DOC-26608, but this doesn't seem to be compatible with the card I have.
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VI to convert input signal from NI 9402 into a rpm value based on pulse frequency
Hello,
I am looking for a VI to convert an input signal from NI 9402 into a rpm value based on pulse frequency. Is there such a thing that exists in the national instruments library?
I am running LAbview 2014 embedded control and monitoring suite on a cRIO 9802 high performance integrated system with NI 9402, 4-Channel, 50 ns, LV TTL Digital Input/Output Module, ultra high-speed digital I/O module for cRIO.
Any help would be greatly appreciated.
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Can TBX-68 Connector block used for PXIe-6363 card with Cable SHC68-68-EPM?
Hi All,
For our application we choose for DIO card PXIe-6363, cables SHC-68-68EPM (192061C-02) and selected connecter block as TBX-68, can you let us know if we can use TBX-68 instead of SCH-68A?
We were looking for unsheilded connector block, so we selected TBX-68.
Thanks in advance, please suggest.
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6221 pulse generation using external digital trigger
Hi there: I am trying to do something very basic, but cannot figure out how to do it. I have an NI 6221 USB I/O device. I want to program it to generate a digital output 100ms after receiving a digital input. I am trying to create a task to do this using NI Max, but all of the options on the trigger source menu are greyed out. There is no way to specify an external hardware trigger. Do I have to program this functionality using DAQmx in the code?
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pci6503
I am using a PCI6503 card to do simple digital output. I have been able to exercise the card in NIMAX, so I know it works. The card will be used in automated testing, so I do not want to use Labview, etc. I plan to write my code in C (or C++). The best I can determine, VISA is the route I want to go. In the documentation, I read if VISAIC, but this utility does not even show my card (it does find a serial port and a printer port.) Can you tell me if I have missed some step in installation? Please be explicit-I am new to NI products.
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fpga-NI USB-7855R Analog Generation
hi.
In a project, i have choosen NI-USB-7855R for a project for generation of Analog Output.
According to datasheet, 7855 have 1us of update time with 16bit Resoulation.
i am little confuss about the 1us update time. make me corrent if i am wrong. the transition time for 1V to 1.2V (1.2V As in algo), will be 1us?
Datasheet: http://www.ni.com/pdf/manuals/375943a.pdf
Waiting for the response.
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Matlab and USB 6008 based problem.
Dear Guiders,
I am using NI-USB 6008/ Matlab Platform to supply external triggering to operate the camera. I could able to trigger the camera using 6008 & Matlab dataacquistion toolbox, but the problem is 6008 digital pulses are not accurate.
ex: If I define 80 millisecond pulse train to one of the digital channel, I expect the 6008 to generate 80 digital pulses. But when I analyse the pulses on oscilloscope, I found two different problems
1) The digital pulse is not accurately 80 ms, but it is 90 ms.
2) The sequence of pulses are not consistent, it is fluctuating between 90ms and 100ms.
Does it has anything to do with Matlab compilation or ......
Thank you in advance for your support.
Reddy.
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nidaqmx.lib
Hello,
I am trying to create a c++ console application in Visual Studio Express 2013 which will control a PCI6503 card. All I want to do is output digital values. I took the WriteDigChan example and pasted it in the program stub that VS creates (it includes stdafx so I can use printf without having to worry about creating windows, etc.) I get the following errors during linking:
Error 1 error LNK2019: unresolved external symbol _DAQmxCreateTask@8 referenced in function _wmain
Error 2 error LNK2019: unresolved external symbol _DAQmxStartTask@4 referenced in function _wmain
Error 3 error LNK2019: unresolved external symbol _DAQmxStopTask@4 referenced in function _wmain
Error 4 error LNK2019: unresolved external symbol _DAQmxClearTask@4 referenced in function _wmain
Error 5 error LNK2019: unresolved external symbol _DAQmxCreateDOChan@16 referenced in function _wmain
Error 6 error LNK2019: unresolved external symbol _DAQmxWriteDigitalLines@36 referenced in function _wmain
Error 7 error LNK2019: unresolved external symbol _DAQmxGetExtendedErrorInfo@8 referenced in function _wmain
Error 8 error LNK1120: 7 unresolved externals
I did add the include and lib directories to the path and get no complaint that the linker could not find the lib-so I assume that is not the problem.
Can anyone help?
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NI 9401 at startup is outputting a value greater than 4,000,000,000
I am using DAQ Assistant to read linear displacement from a NI 9401 in a cDAQ 9178 chassis. On some ocassions, when I load the VI and start logging the position before there is any movement, the NI 9401 outputs values as high as 4,294,967,241. It slowly counts down and then when there is actual movement, the NI 9401starts counting the position from 0. On other ocassions, it starts normally from a position of 0. Does anyone know what this large value refers to and why it is being output?
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Configure multiple HSDIO devices for synchronized pattern generation and acquisition using HWS files
Dear NIDev Community,
I'm currently looking into implementing an application for digital pattern testing of a high channel count device.
The example that closely matches my application is the memory test reference design from NI web (did_mem_test.zip).
Memory Test Reference Design
http://www.ni.com/white-paper/7966/en/
In the reference design, a single HSDIO device is used to generate a write and compare pattern and the errors analyzed. In my application, I will need to distribute the digital signals across several HSDIO modules since each module has limited digital lines.
Module 1 and 2: Data lines
Module 3: Address lines
Module 4: Clock, chip enable, etc.
I would need your kind help to understand how I should implement the reference design to fit an application that spans across several modules. If you are able to give me a simple example code I will be able to move ahead from there.
My intention is to use HWS waveform patterns created using the Digital Waveform Editor and if possible to use NI-TCLK to synchronize the devices. I have attached a VI that I had modified from an example program but I'm not sure if I'm implementing it correctly. I've also zipped the reference design code too.
I'm using four PXI-6551 devices and LabVIEW 2013.
Thank you for your kind help. 
Cheers!
Sanka
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scb-68 and PCI-8331 what is converting my analog sgnal into digital%3F
Long ago, around 7 years ago, I worked on a project in which I interface photodetector to my computer through SCB-68 kit. The SCB-68 kit was connected to computer using PCI-8331 card.
Now, my input was analog signal from photodetector but at programming interface I was getting digital values for computation. Now my confusion about the conversion task done by which part of this connection?
SCB-68 was converting the input signal and supplying digital output? or PCI-8331 was doing digitization before delivering information to computer? or labview itself was doing it after getting signal from PCI-8331?
can anyone please clear me?
Thanks!
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