Re : SPI Digital Waveform Library

[nafe]

Hi, I want to make a 40 bit, 60 bit, 120 bit, etc. (higher than the 32 bit) SPI clock using labview. I know that SPI digital Waveform Library can do this but I don't have this in my system. Where can I find this? Do I have to buy a "license" in order to have this library? I have Labview 2013.

As alternative to SPI Digital Waveform Library, I want to add U32 and U8. How can I implement this?

I would appreciate any help that you can provide me.

Thanks,

Anna

[gr3g]

Hello,

I use a PCie-6320 DAQ for implementing a SPI communication. I have trie the example gave in NI website : http://www.ni.com/example/31200/en/ that I modifiy to fit with my system.

This is perfectly working. I can easily control multiple slaves with datas that i send to them. (Check with an oscilloscope).

However, I have some issues to receive datas from the slaves. The MISO line seems to not respond.

1) When I try to display the data on the MISO line, labview code returns me an error : 200562. Error while executing DAQmx Write. The datas are not supported. Value = 5, Supported values : 0,1

2) When i try to display the data on the MISO line with an oscilloscope, no data is transmitted on the line.

I don't know how to manage this problem. Does someone could help me ?

I attached my Labview code on this commentary.

Thank you for your answers,

[nmolla13]

I am trying to use the SPI Digital Waveform Library to generate a signal to send to a MAX 5484 Digital Potentiometer using a cDAQ with an NI 9474. The waveform being generated seems to be correct, but the digital pot is not working. Is there possibly something wrong with how I am using the library or my instrumentation or timing? I have attached a picture of the block diagram.

[gr3g]

Hello,

I carried out a SPI communication with the SDW library with a 16 bits data format. This is working perfectly. However, I have to improve my labview code in order to manage a 32 bit data communication. Unfortunatly, the library seems to not work this format. In fact, when I change my data (16 bits to 32 bits), my clock is changed by the library but it's configured for a 64 bits data format. 

Does someone have the same problem ? Is there a problem in the SDW library for the 32 bit data format ? 

I attach a picture of my problem, it could help you to answer to my issue.

Thank you for your answers,

GL

[MarekSzczygiel]

by default SDW library formats data in 8-bits chunks, and changes CS line state. In application I was using it, this behaviour was not accepted, so I've modified it not to change CS state during transmission, but do it only once when all data are send. Since that I do not care how much bits I send...

Change was in Add Last Bit-fmt1.vi

[jais007]

David,

In the example vi, found that the following combination of input values doesn't produce the SCLK line data.

 

Debugged and found that it is a bug in the SPI Digital Waveform Library in the following three subVIs.

Add Middle Bit-fmt1.vi

Add Last Bit-fmt1.vi

Add First Bit-fmt1.vi

In all the three VIs, inside the below case structure (in default case), the constant value in the selector is 0 and 1 as commented below.

 

But in the other case (Case 0), the constant values are 1 and 0 but it should be 0 and 1. 

Please fix the above metioned issue and let us know the status on the same.

Thanks,

Jaishankar

[jais007]

David,

Any update on the above mentioned issue?

Thanks,

Jaishankar

[Austin-Downey]

All,

Thanks in advance for taking the time for trying to try and help me sort though some problems.  I will try to be as concise as I can in relating the problem.  I consider myself fairly proficient with LabVIEW but I cannot seem to get this application to work.   

What I need – (1) To be able to use input data from SPI supproted chipts into my LabVIEW vi's. (2) My first attempt is trying to receive data from a TC77 thermal sensor over its SPI interface.  

Hardware – cDAQ-9174 with a NI-9402 high-speed DIO.  (see attached picture) I am running LabVIEW 2014 on a windows 8 machine.  (Version 14.0)

Slave sensor – Microchip TC77, temperature sensor.  This chip send a 16 bit word, clocked on the rising edge of the clock. 

Problem – I am running the internal clock code from the .zip examples found at http://www.ni.com/example/31200/en/. I selected the appropriate physical channels, (see .vi and picture) and run the code only to receive the error

Error -200452 occurred at Property Node DAQmx Export Signal (arg 1) in Init IntClk Device.vi->DAQmx SPI - Internal Clock-Austin Downey.vi

Possible reason(s):

Specified property is not supported by the device or is not applicable to the task.

Property: DataActiveEvent.OutputTerm

Task Name: _unnamedTask<9AE>

Main Question – Is this a hardware issue of a software issue?  Is this possible given the hardware I’m using?  

Side Question – Is SPI (send and receive) communication possible on a cDAQ?  I also have a cRIO (9042) that I can use if that would make it possible. However, I would like to stay with the cDAQ if possible.  

I am very motivated to get this working.

Thanks again,

Austin Downey.   

[TheEngineeringBear]

Hey Austin,

Does the Microchip TC77 have a DLL that could be used in LabVIEW?

I checked out you VI and I may just not understand what you are trying to do, but are you not using DAQmx?  Cause there are no channels that seem to be created or tasks.  

Can you point out/make sure you are creating the channels and tasks in LabVIEW?

-Bear

[TheEngineeringBear]

Does this help???

http://forums.ni.com/t5/LabVIEW-Embedded/EK-LM3S8962-TC77-temperature-sensor-reads-OK-SPI-interface/...