Compiling and Sending UDP Packet

MIT App Inventor Help
1

I do not understand UDP at all, and I could use some help figuring out some code to construct a UDP packet (If I even need too). I am using this documentation for the packet layout (GitHub - v1993/cemuhook-protocol: Mostly complete cemuhook protocol reference), but I am completely lost on how to implement this. Currently, I have figured I need the UDPXmitter Plugin and Byte mode on, and have written this thus far, but the server does not receive anything:
Capture

Any help is appreciated

2

Where did you find that extension? Any link?
You might want to ask the author

Taifun

3

Its this AI2 UDP extension: Ullis Roboter Seite/AI2 UDP

Even when looking at the documentation on the extension, I dont see anything that would allow me to create like Packet Headers and Mesaage types, which I need for the server to understand my input.

4

the author @Ulrich_Bien might be able to help
Taifun

5

You can't code a Cemuhook message as you did.

  1. You can't join strings via a list. You have to use then join block.
  2. The extension is not able to mix strings ("DSUC") and binaries ("0x10"). You have to encode "DSUC" to its ASCII equivalent: 0x44, 0x53, 0x55, 0x43

Are you sure that the receiver is not receiving? Or does the receiver not understand what you are sending?

You can send your message code to a label to see, what the transmitter gets for xmitting.

Please send further questions via e-mail (bienonline (at) gmx.de).

6

Your packet is malformed too. The CRC32 is missing and the packet length is wrong.

7

We prefer to have the discussion in the community
Answers might be helpful also for others in the future...
This is the purpose of a community
Thank you

Taifun

8

I fixed the Joining of strings and encoded DSUC, however I am not sure which string i need to change for CRC32 and the same for packet length.
image

9

There are still separators missing. You will get
"0x44, 0x53, 0x55, 0x430x10, 0x010x00, ..."
---------------------------------!--------------!-----

I told you to display the result in a label. Why don't you do that? Then you would have seen that the string is not correct.

There are various ways of calculating a CRC32 checksum: https://en.wikipedia.org/wiki/Cyclic_redundancy_check#Standards_and_common_use
Unfortunately, this is not described in the GitHub entry.

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