Event Structure in Timed Loop in real time cannot work

[Wenxi]

I am a new user for LabVIEW. And I met a problem which really frastre me!!! Hope someone can help me out. Thanks in advance!

I simply want to use event structure under timed loop, which is extrmely important in my design.

However, this works very good in my computer (without connect to FPGA).

Once I connect it to FPGA, then I can run it still but there is no response!

My file is attached. Please somebody helps me!

Looking forward to your answers!

[Wenxi]

By the way, if it is not possible to use event structure in Timed loop, then how can I design some same strategies instead?

Please somebody help me! 😉

[GregFreeman · Accepted solution]

The FPGA runs headless. Event structures are not going to work. What you need to do is have an application on your host where the user presses a button, changes a value, etc. That event should send a message via TCP/IP to the code running in the real time environment. Then the real time environment should set a control on the FPGA to the value you want.

In general, real time programming with FPGA has multiple layers.

1) Host code-> handles user interactions and communicates them to real time code via TCP,UDP, etc. Displays data to user sent from the RT controller.

2) Real time code->runs headlessly. Handles messages from Host code, processes FPGA data, communicates with FPGA much like the host code communicates with the real time code

3) FPGA -> does acquistion and passes it via FIFO to the RT

The first thing you need to do is understand the architecture and how all these pieces of the puzzle work together before throwing things down on a diagram.

[Wenxi]

Thank you so so much!

After reading your reply, I got a brief picture of the NI architecture. And I moved some of my code into host computer file, then it works totally fine.

The reason why I didnot get into the architecture too much is I just followed some former students' work for my thesis. They designed all the file in the remote part. Now I knew host file->"my computer"; FPGA file ->"cRIO 9104".

Thanks again!

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@for(imstuck) wrote:

The FPGA runs headless. Event structures are not going to work. What you need to do is have an application on your host where the user presses a button, changes a value, etc. That event should send a message via TCP/IP to the code running in the real time environment. Then the real time environment should set a control on the FPGA to the value you want.

In general, real time programming with FPGA has multiple layers.

1) Host code-> handles user interactions and communicates them to real time code via TCP,UDP, etc. Displays data to user sent from the RT controller.

2) Real time code->runs headlessly. Handles messages from Host code, processes FPGA data, communicates with FPGA much like the host code communicates with the real time code

3) FPGA -> does acquistion and passes it via FIFO to the RT

The first thing you need to do is understand the architecture and how all these pieces of the puzzle work together before throwing things down on a diagram.

---

[GregFreeman]

Nice! sounds like you got it.