By David Akinpelu
I am implementing a TCP connection between MyRio(client) and Python(server). The goal is to send data from the server to the client, perform some calculations, and send the result to the server. I need to keep changing the data being sent to the client. I noticed the first data works fine and the result returned to the server, but the client could not read subsequent data. I debugged and was able to detect that the error is coming from the first read function is the "Reading values subvi" but I don't know how to correct it. How do I go about it?
I have attached the files below.
Reading Unknown Bytes from TCP.vi Second_client.vi SimpleServer.py
Hello, I'm trying to send data from my RPI b+ to labview and store the information in a spreadsheet, right now the data I'm using is just a sawtooth generated in the python code but eventually it will be sensor data adquired via spi, the data comes at =~ 6-7khz but the time it takes to send the data to labview is much greater, I fear the circular buffer I intended to use to store the data before sending it via tcp will get filled pretty fast. I'm not very experienced in either python nor Labview, I was wondering if i could get some advice in the optimization of the code.
I attached the VI of the client and a VI that graphs the data on the spreadsheet, also the python code.
Thanks in advance, sorry for the mess.
First time LAVA poster here with my first question. Why do some LabVIEW programmers insist on wiring the error cluster to the bottom of their VI as opposed to the sides as shown in most NI documentation. Is there any benefit to it? Is it 100% a preference thing? Is there a way to make LabVIEW connect error wires like this automatically?
I've only seen it in advanced LabVIEW code from experienced programmers and some parts of the Actor Framework.
Your insight and experience is appreciated!
The introduction of parallel, read-only access for DVRs in LabVIEW 2017 adds a great deal of flexibility to using DVRs to monitor values in parallel executions of code. Fo\The downside of this, of course, is the necessity of using the In Place Element (IPE) throughout your code simply to read the value. Having IPEs throughout your code just to read a value both takes up block diagram real estate and also takes more clicks than desirable to insert.
Similarly, though less frequently, there are times when you only need to update the value within a DVR without actually performing any logic inside of the IPE. This situation is less frequent, at least for me, as I am usually using arrays or classes with DVRs such that I actually need to modify the existing data rather than simply replacing it.
A more preferable solution to the above situations would be to have Read/Get and Write/Set VIs for the DVRs to simplify the process of working with them. This way, and IPE on the block diagram would only be needed when you were actually modifying the existing data within the DVR, rather than simply overwriting or returning the current value.
Thanks to the power of malleable VIs and the type specialization structure that is now officially released in LabVIEW 2018, a better solution is now available. I’ve created two malleable VIs, Read DVR Value (Parallel) and Write DVR Value that allow you to perform a write and a parallel read on any DVR data type.
Now, you can use a single VI that you can insert via Quick Drop to read or to write DVR values.
Download the attached ZIP file to access the two malleable VIs and example code, and please let me know your thoughts in the comments!
DVR Read and Write VIs 1.0.0.zip
I have a simple program which has only 2 buttons for the user interface. When the user clicks OK I want the program to get into the event structure case called "OK Button". Once it is inside there is a loop which continuously waits for 1 second until "Stop Button" is called from the user.
But because once the user presses the "OK Button" the program gets into the event and therefore I can not call the "Stop Button".
Is there a way to call the "Stop Button" even if the program is inside the event ?