Real-Time FIFO instead of "Chart History Length"

[Cashany]

I was wondering how I can implement the following method with Real-Time FIFO instead of "Chart History Length"

[uChiron]

Here's NI whitepaper about RT FIFO. I would suggest u to read more specifically in first and third section (Using RT FIFO):  http://www.ni.com/white-paper/3934/en/

[Cashany]

Is there any way to read all the data inside a RT FIFO regardless of the size of the FIFO or the amount of data available in the FIFO?

I mean in every iteration of a loop, I want to read all the data in the RT FIFO and make the RT FIFO empty. 

[thoult · Accepted solution]

Yup. It uses two FIFO read nodes. The first one reads 0 elements, and the output for Element Remaining is wired to the second node's Number of Elements input. Voila, you check what's in the FIFO and pull everything out of it.

[Cashany]

Got it.

[Richard1000]

So how does one read 0 elements from the FIFO?  Are we discussing the RT FIFO Read (primitive) or the Shared Variable with RT enabled?

[Cashany]

Actually, In every iteration of the loop, I will write 100 elements to the RT FIFO and then will read all the remaining elements from the RT FIFO. 

When I write to the RT FIFO I can get the number of elements remaining in the RT FIFO, then I can wire the number of elements to my read function.

So, in my case I don't need to read 0 elements from the RT FIFO. 

Sorry, I couldn't help!

[uChiron]

FIFO node in RT host :]    Just little trick to pull everything from the queue.

[Richard1000]

This is a Property Node, right? ... thanks, I'll read up on them!

[Richard1000]

Ok this is not a Property Node, but a Method Node, correct?

Ref: http://zone.ni.com/reference/en-XX/help/371599G-01/lvfpga/fpga_fifo_method/

Since this is for taking action on a FPGA VI, would the node be available if one is running the cRIO in Scan Mode?