[Deprecated] SPI Digital Waveform Library

[FM82]

Good day to all of you,

I'm working on a complex project, that involve even SPI comunication, in a DC-DC Converter. I need to sniff the comunication beetwen microchips inside the board and to do this my boss purchased the NI-PXIe 6124. I managed to obtain the digital input waveform but the request from the costumer is to translate the waveform in bytes form. I had download the SPI Digital Waveform components for Labview but i can't understand how to make the translation. Any help would be really appreciated.

Thank you in advance,

Francesco

[stevesteve]

As you want to read SPI data rather than just write data then the I/O needs to be synchronised so I think you will struggle with a 6124 card as I don't think it has the facility to synchronise inputs & output ports at the same time; some High Speed NI cards have the facility. However I think you would be a lot better off with a dedicated SPI card such as the NI USB-8451(depending on speed).

[FM82]

First of all, thank you.

Now for the question: I don't understand why you think i need syncronized I/O since for this task I only had Input Signals. Did I miss something?

Francesco

[stevesteve]

I am guessing from what you said that you are just trying to monitor SPI transfer between two existing devices?

If that is the case then to read via I/O, the SPI Clock & Data lines need to be read on the same input port at the same data (synchronised) at a fast rate (whatever your SPI speed is (400kHz)?). The Daq card that you have is not High Speed and so wont be able to sample the input port anywhere quickly enough.

[FM82]

Ok, now I understand what you said. I'll double check the Daq Datasheet and see what we have. But even if I correctly sampling the SPI how can i decode it?

[stevesteve]

To decode it you first need to know the SPI speed, SPI mode & whether MSB is sent first or last.

[FM82]

So there is no a library with pre-built decoding. I downloaded the SPI Digital Waveform library but for what i understand is only for creating a digital waveform that must be sent with NI DAQ device, am I right?

[stevesteve]

There are SPI libraries that come with NI SPI hardware (eg NI 845x). DAQmx has its own read/write I/O shipped with the driver. HSDAQ also has its own different library shipped with the hardware (eg NI 653x).

[m.solo]

Hi, Good day to you all. 

I have been trying to implement an SPI communication with the USB6210 as master to cummunicatie with a pic18F microcontroller.
I have downloaded 

• serial_wfm_1_0_1_lv82.zip ,
• serial_wfm_1_0_1_lv85.zip ,
• serial_wfm_1_0_1_lv86.zip 

from

"Serial Protocol Communication Reference Design for Digital Waveform Devices ".
https://forums.ni.com/t5/Example-Code/Serial-Protocol-Communication-Reference-Design-for-Digital/tac...

but when trying to run this and test it I keep getting an error.
the error is as follows:

"Specified read or write operation failed, because the number of lines in the data for a channel does not match the number of lines in the channel.
If you are using the Digital Waveform datatype, make sure the number of lines in the digital waveform matches the number of lines in the channel.
If you are using boolean data, make sure the array dimension for lines in the data matches the number of lines in the channel.

Number of Lines in Channel: 1
Number of Lines in Data: 3

Task Name: _unnamedTask<1C>"

I have not made any changes to the VI itself. But keeping getting this error.
I tried running it with highlited execution and saw that the problem occurs at the init CorrDIO device.vi

are there any suggestion?

thnx in advance.

[CL_eisenwr]

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@Christian_L wrote:

Please provide feedback, comments and questions on the SPI Digital Waveform reference library in this thread.

- David

(posted by Christian on behalf of David)

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The link to the example code now appears dead. Could someone at NI take a look and restore/fix it?