byte packet[] content

[LZsolt75]

As I compare your code with tomasvilda's code I have realised that the array packet[] in your code has different content than the array fullTray[] in tomasvilda's code. Not only the values of the elements but the length of the array is also diffierent.
Why is this difference? In your code only the 11th an 42nd element is overwritten.
And also a notice: It would be helpful if you write somewhere what kind of board is the code for. I am asume that it is for arduino, while tomasvilda's is for Attiny85.

[prj]

For digispark (ATTiny85) I made a fork here:
https://github.com/prj/xiaomi-humidifier-water-sensor-digispark

The packet used in this project works just fine, I have two of these humidifers and it worked for both.
42nd element is checksum.

thomasvilda captured everything - initial handshake as well, not just the recurring data packet, whereas the author of this repo realized that it is enough to just send the data packet and omit everything else, and the top board is still happy with that.