Bluetooth Classic on Arduino Uno R4

Official Hardware UNO Family UNO R4 WiFi
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Hello there, I am new to this world so forgive me for any nonsense I might say.

I have an Arduino Uno R4 WiFi which (as far as I understood) has Bluetooth capabilities thanks to the ESP32-S3.

I want to detect when a Bluetooth device (mainly my phone) gets close to the board.

Looking for something similar I bumped into this thread: [SOLVED] Detect specific Bluetooth MAC address and trigger relay when detected.
Which suggests to use the Bluetooth Classic connection instead of the BLE since, this way, it is easier to get the device MAC address that allows to identify it.

I also found this support page: Boards and shields with wireless connectivity; which states and I quote:

Although the communication modules on these boards can also use Bluetooth Classic, it is not currently supported by official firmware or libraries.

After some research I found that for this type of communication the BluetoothSerial.h library is used, which is part of the ESP32 board, such as the Nano ESP32.

I installed the ESP32 core but I was not able to import this library in my Arduino Uno R4 WiFi sketch.

Is there a way to make this work?

This was not my first idea, I leave the details of what I tried to do in the spoiler below.

Previous plan using BLE

At first I tried using the BLE via the ArduinoBLE library which I managed to get working thanks to this thread: Radio module firmware version 0.2.0 is now available.

The idea was to let the Arduino send an advertise and listen for connections. This approach kinda worked but it led to some problems:

  1. The phone complained that An app is needed for this device to work but by pressing Pair it manages to connect anyway. I am no expert in BLE but I think this could be fixed passing the correct BLEService UUID

  2. After the phone Bluetooth is turned off and back on the board can't be reconnected. It must be unpaired and paired from scratch (which defeats the original purpose and is not very user friendly)

  3. This way any phone could see the board and connect to it. To fix this I thought that I could make the advertise last only a few seconds (just like a pairing mode in many Bluetooth devices)

I would like to add that the security issues brought by this approach are not a concern since this program will not be used in security critical applications.

If you have any idea on how to solve these issues I might consider going back to the BLE solution

Thanks in advance to whoever decides to help me :people_hugging:.

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No. The Uno R4 uses an ESP32 S3.

The S3 has no Bluetooth Classic hardware in the chip.
Only the "old" ESP32 can do it - no other Espressif SoC has BT Classic.

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The Arduino UNO R4 WiFi merges the RA4M1 microprocessor from Renesas with the ESP32-S3 from Espressif, creating an all-in-one tool for makers with enhanced processing power and a diverse array of new peripherals. With its built-in Wi-Fi® and Bluetooth® capabilities, the UNO R4 WiFi enables makers to venture into boundless creative possibilities. Furthermore, this versatile board boasts a convenient on-board 12x8 LED matrix and a Qwiic connector, offering ample space for innovation and unleashing creativity. This dynamic combination empowers makers to transform their ideas into reality and elevate their projects to unprecedented heights.

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Thank you for the copy of the marketing BS from

Do you have a point to make ?

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I had not noticed my text fell off when I copied/pasted it.
What I had meant to ask is:

The Marketing suggests this has built-in WiFi and Bluetooth. Is this just misleading information from marketing and the Bluetooth capability is the same as any other capability to add components?

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The Uno R4 WiFi does have both WiFi and Bluetooth. What could have been clearer is that Bluetooth Classic is not supported

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