https://arduinojson.org/
ArduinoJson: Efficient JSON serialization for embedded C++
ArduinoJson is a JSON library for Arduino, IoT, and any embedded C++ project. It supports JSON serialization, JSON deserialization, MessagePack, streams, and...
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https://forum.arduino.cc/t/arduinojson-und-floats/1025017
ArduinoJson und floats - Deutsch - Arduino Forum
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