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how to send a SQUARE WAVE to PXI-6259 over the LAN

Dear HaI L, thanx a lot for ur reply,
for the first two question I would like to say that I am on a  client computer. I am sending some screen shots they will be helpful.

How can I write values to the variables, can u plz explain in detail?

I am having some problem in the knwledge base that u sent me, i am following it but  I am unable to create a NI DAQmx channel,  the variable I can create and link it with the global virtual channel. where is the server explorer located?

Thank u.
Munir
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Message 11 of 23
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two other screen shots are as follows.
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Message 12 of 23
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Hi Munir,

I see that you are using a real-time system. This is how you are able to modify the device on the host computer from MAX on the client computer and will make running your application much simpler. All you need to do is connect to the Real-Time target system when you open LabVIEW and then you can run the analog output examples from the example finder and it will update on that system. More information about using a real-time system can be found in the Real-Time User Manual. You will not have to worry about shared variables now since you are using real-time.

Regards,
Hal L.
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Dear HAI L,
Thank u for the real time user manual, it would be very helpful if u could send me the exact name of the vi in the example finder, it would really help me a lot. The manual seems to be old, and does not contain "shared variables".  do u think I still need the Shared variable and NI DAQmx  OPC capabilities for the program I want to make.
Thank u.

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Message 14 of 23
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Hi Munir,

You will not need to use shared variables or OPC for your application since you have a real-time system. I was not aware that you had a real-time system until I saw your MAX screenshot. A good example for continuously outputting a waveform is Cont Gen Voltage Wfm Int-Clk. Go to Help >> Find Examples >> Hardware Input and Output >> DAQmx >> Analog Generation >> Voltage. The Real-Time Help Manual should help you set everything up and configure your system. Please let me know if you have any problems with this.

Regards,
Hal L.

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Dear HaI L,
I am a little confused about all this now,  I am using a real-time  system, but it is not connected directly to the host computer, it is in the lab, and the host computer and the client computer are conneted to each other by ethernet. 
So my question is how can i send a siganl for eg.  a square wave to the target or client if I do not use the OPC or shared variable?
I think variable would be an easy way . what do u think?

Sincerely,
Munir
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Message 16 of 23
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Hi Munir,

The simplest way to transfer data between your host computer (your windows desktop system) and your target controller (your PXI RT controller) is by using shared variables. Once you have transfered the data from your host to your controller, you can deal with the data any way you want to. The link below gives more information on the new features of LabVIEW RT 8.0. The 3rd link (Simplify Real-Time Communication with the LabVIEW Shared Variable) walks you through creating shared variables and using them transfer data. http://www.ni.com/realtime/features_and_related_products.htm

Regards,
Prashanth

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Message 17 of 23
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Thanx a lot prashanth and HaI L,
i have succeeded in sending a sine wave to my desired channel, using the shared variable. Smiley Very Happy
take care.Smiley Wink
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Message 18 of 23
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Dear Prashanth,
I am using a real time system PCI-6259 M-series and using NI DAQmx 8.0.
 I have made a  DAQmx  VI and I need to specify a channel to send the signal , as the real time system is not connected to my computer so I cannot choose any physical channels,  how  can I choose  a  channel ( a  global  virtual  channel ) in the DAQmx Program?

Is it possible or not and if not is there any other way to do this?

My second question is I am using NI-DAQmx 8.0 , will installing  "NI-DAQmx Base Version 2.0 for RTX" which also supports M-series boards, will  be helpful for me?
 
Thank u,
Sincerely ,
Munir Afzal Bhatti.
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Message 19 of 23
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Hi Munir,

If I understand correctly, what you want to do is programmatically select your DAQmx channels to send data to. You can accomplish this by using DAQmx Task constant or DAQmx Task constant in the block diagram code. The programmatic control of DAQmx channels and tasks will be the same as in windows. http://ae.natinst.com/operations/ae/public.nsf/web/searchinternal/3a1d9e4a6ca8eca586256fc000768694?O...

Regards,
Prashanth

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