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BLE Walkthrough: https://wiki.seeedstudio.com/XIAO-BLE-Sense-Bluetooth_Usage/ & https://community.element14.com/technologies/internet-of-things/b/blog/posts/seeed-xiao-ble-sense-nrf52840 & https://wiki.seeedstudio.com/XIAO_ESP32C3_Bluetooth_Usage/ & https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_nrfconnect_ble%2FUG%2FnRF_Connect_BLE%2FnRF_Connect_intro.html