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 List of approaches
 
 - [ESP8266/ESP32, C++](tools/esp8266/) 👈 the most effort is spent here
-- [Arduino Nano, C++](tools/nano/NRF24_SendRcv/)
+- [Arduino Nano, C++](tools/nano/NRF24_SendRcv/) - serial IF only (AhoyUL) e.g. for FHEM
 - [Raspberry Pi, Python](tools/rpi/)
 - [Others, C/C++](tools/nano/NRF24_SendRcv/)