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margarette
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Re: waveform recording in NI RFSA phase coherent multi channel

Here is the recorded waveform (in xml file) that I am trying to regenerate. I can't attach an xml file that's why I just copied it to a Word document. Thank you.

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margarette
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Re: waveform recording in NI RFSA phase coherent multi channel

[ Edited ]

I've tried another VI and it's called Playback data.vi. It uses a binary file to playback a data.  The binary file is saved on my desktop. However, there is still an error when I run it. It says that the file can't be found. Where should I save my file such that there will be no errors? Attached is the screenshot of the error. Thank you :smileyhappy:

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James_M.
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Re: waveform recording in NI RFSA phase coherent multi channel

Hi Margarette,

 

Where did you get the code that you're using? The latter part of the error message references NI-488 (GPIB driver), which implies that you're not using RFSA code. Also, the XML file references a binary file for the actual data storage - Channel 0 Data (PXI1Slot3).bin - do you have that file as well?

 

All the best,

James M  |  Applications Engineer  |  National Instruments

James M. | Applications Engineer | National Instruments
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margarette
Posts: 34
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Re: waveform recording in NI RFSA phase coherent multi channel

Hello Mr. James M,

 

Thank you for your reply. I was already able to playback (using PXIe-5673 Phase Coherent Playback with NI-TClk Example). Now my problem is how to convert the Channel 0 Data (PXI1Slot3).bin file into an Excel file such that I can see the value of the elements. How can this be done? Thank you so much.

Member
Andy_Hinde
Posts: 177

Re: waveform recording in NI RFSA phase coherent multi channel

Hi Margarette,

I may have suggested this already but I encourage you to join the following forum on NI Community if you haven't already (NI RF Multi-Channel):

 

https://decibel.ni.com/content/groups/rf-multichannel

 

I have recently posted an updated version of both the RF Multi-Channel and RF Phase-Coherent Multi-Channel reference architectures - version 1.1. Please download and try out this updated software.

 

I have recorded a video demonstrating a 10 second Record and Playback (Playback is looped) process using a 4 channel acquisition and 4 channel generation (4x4) MIMO setup. Hopefully this can address any questions you have posted previously that were inquiring about how to get this process working. Please view the online video here:

 

http://screencast.com/t/uhIcFK2ns

 

Finally, I've addressed your question about reading the binary data values, converting them to floating point voltage values, and then writing them to Excel in an additional post at the aforementioned NI RF Multi-Channel page. Here is a link directly to this:

 

https://decibel.ni.com/content/docs/DOC-21389

 

Regards,

Andy Hinde

RF Systems Engineer

National Instruments

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margarette
Posts: 34
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Re: waveform recording in NI RFSA phase coherent multi channel

Hello Mr. Andy

 

Thank you so much for all your help! This forum really helps me a lot. I was already able to record and playback waveforms using RF Multi-Channel and RF Phase-Coherent Multi-Channel  - version 1.1. But I'm sorry to bother you again with another question. It is regarding the Read PC Binary Data File and Write to Excel.vi. When I specify the XML Metadata File Path (I input the Record Metadata xml file), error 1430 occurs. It says "Open/Create/Replace File in Read PC Binary Data File and Write to Excel.vi<APPEND> <Not A Path>." How can I solve this problem? Thank you so much!

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Andy_Hinde
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Re: waveform recording in NI RFSA phase coherent multi channel

Hi Margarettem

The error message indicates some problem with opening a file. There are three files that get opened as part of this example VI:

  • The XML metadata file
  • The binary data file
  • The tab-delimited text file (Excel) file

Can you turn on Highlight Execution and watch the LabVIEW block diagram when you run this to determine where the error is originating? There are also three paths used to point to these three files for the File Open routine, two of which are created programatically. The error seems to indicate a problem with one of these paths, so can you check these three file path wires with a LabVIEW probe to see which one might have a problem?

 

Regards,

Andy Hinde

RF Systems Engineer

National Instruments

Member
margarette
Posts: 34
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Re: waveform recording in NI RFSA phase coherent multi channel

Hello Mr. Andy

 

Thanks for replying. Upon checking, I think the error comes from xml metadata file path. But I can't think of any reason why there is an error.

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margarette
Posts: 34
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Re: waveform recording in NI RFSA phase coherent multi channel

Hi sir andy!

 

I will attach a screen record when I tried to run the VI. I also recorded the block diagram after I pressed highlight execution. Thank you.

Member
Andy_Hinde
Posts: 112

Re: waveform recording in NI RFSA phase coherent multi channel

Hi Margarette,

I watched your video, thanks for posting that. I think the problem is you are not entering the number of channelsthat were recorded and whose metadata is stored in the XML file into the Total Number of Channel in XML File control on the front panel. It generates an error in the Configure Record Playback Metadata subVIwhen you leave this values set to zero. This subVI also returns an empty path when this happens and the subsequent File Open VI then errors out.

 

Enter the correct value for this control on the front panel and see if this corrects things.

 

Regards,

Andy Hinde

RF Systems Engineer

National Instruments