SPI communication with Arduino Uno

[deepen_solanki]

Hello, I am a beginner in LabVIEW and I have a myRIO 1900. I am trying to communicate between myRIO and Arduino via SPI and I have a few doubts

1) Using Arduino, I am trying to send data in this fashion :

for(i=1;i<=255;i++)

SPI.transfer(i);

When I send the 'i', my impression is that the value of 'i' is sent as a stream of 8 bits. Correct ?

2) How do I read this value in myRIO and make sense out of it ?

I have attached my VI that I tried to write. 

What does each frame contain ? Does it contain the stream of 8 bits ?

In the SPI Read, what is Frames Read ? Frame Count ?

How do I isolate the meaningful data from there ?

How does Frame Length in SPI configure affect data transmission ?

And how do I match their clock speeds for transmission ?

[Hooovahh]

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@deepen_solanki wrote:

When I send the 'i', my impression is that the value of 'i' is sent as a stream of 8 bits. Correct ? 

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Did you declare the i as a byte?  Or did you do some thing like init i=0;?  If so then it will be sent as a 32 bit integer.

If you do read properly it will be read as the same as it was sent.  I believe you get an array of bytes when you read, so if you sent it as a byte you will get an array with one element.  If you sent it as an i32 then your array will have 4 bytes in it and will be the i32 you sent.  Sorry I don't have any myRIO software installed so I can't test , or look at much.

[deepen_solanki]

I will instead get to my main problem. I want to interface a 16 bit ADC to myRIO. I think the ADC is sending data but I dont know how to read it and make sense out of it. The ADC is ADS8332. Thats why I asked this basic doubt to clear all concepts. 

[Sam_Sharp]

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@deepen_solanki wrote:

I will instead get to my main problem. I want to interface a 16 bit ADC to myRIO. I think the ADC is sending data but I dont know how to read it and make sense out of it. The ADC is ADS8332. Thats why I asked this basic doubt to clear all concepts. 

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Get an oscilloscope and attach it to the clock and data lines - you'll soon figure out if you're sending/receiving any SPI data. If you have a good scope, it may also do SPI decoding as part of its functionality. This is always a good starting point!