This code is written based on the source codes:
https://github.com/handiko/Arduino-APRS https://amperka.ru/blogs/projects/flipper-zero-app-programming-tutorial https://yakovlev.me/hello-flipper-zero/
I express my great gratitude to the authors of these works.
You can read more about using this code in my articles:
https://habr.com/ru/articles/747152/ (in English) https://habr.com/ru/articles/742428/ (in Russian)