How to bluetooth pair Arduino Uno Wifi Rev 2

Hi, is there something I need to do to bluetooth pair a Uno Wifi rev 2 with a smartphone? Cause it doesn't show up under list of pair-able devices when I scan for bluetooth devices with my android phone. Any help would be appreciated, thanks

Welcome to the forum.

If the board uses BLE you do not need to pair. You can just connect from an app.

If you require more help, please post your code and describe what you like to do in more details.

Do you have a Bluetooth module connected to the Uno? The Uno Wifi does not have Bluetooth on board, it would have to be added.

@groundFungus It looks like the Uno Wifi Rev 2 has a NINA module like the Nano 33 IoT and supports BLE.

Sorry, the Uno Wifi that I knew of had an ESP8266 module on the board.

Thank you everyone for replying, I appreciate it. Yeah I have an app that I'm developing for Android phones (still working on that). So I'm guessing thatI have to explicitly write some code on the android side to connect to the Uno?
Or to clarify, do I have to give the user an option to connect to the board, or will it show up when they scan for bluetooth devices from the phones Settings options? I'm looking to remotely control a 12V fan connected to the Uno from an android app that I'm developing.

Have a look at some generic BLE apps. They tend to have a button to start scanning and then you can select a device and connect. You can hide all that, have just one button and select the device by some parameter (service, characteristic, local name) you select.

Yes, I suspect it will involve only a few function calls for the BLE part.

For the BLE the phone settings options is usually not used. There may be some exceptions for HID devices like keyboards. But all other BLE device are handled trough the app interface. The user only needs to enable Bluetooth trough the smartphone OS.

1 Like

Oh ok, I'll look into those. Thanks :slight_smile:

I was using this article (link below) as a template for my project. Do you think it would work with my case? The article uses an HC-05 module for bluetooth connection, but I'm using the builtin bluetooth chip on the Uno Wifi rev 2. Would this cause any problems (since at the end of the article it says that you first have to pair the module with your phone)

I believe the linked article will be useless for you. The HC05 uses classic Bluetooth and the WiFi Rev 2 uses Bluetooth Low Energy (BLE).

The Classic Bluetooth and BLE share the same frequency band, but otherwise they are incompatible. You need to do your research on writing an Android App for BLE.

Oh ok, thanks :slight_smile: Looks like I have some BLE research to do :slight_smile:

I was just looking at the official Arduino store website (link below) and for the Uno Wifi rev 2 it says that it can use classic bluetooth or BLE. So is it maybe possible to indeed use bluetooth with it? It says it can be used as the host or client

It's a major hack which leaves the board without wifi or BLE.

Did you try any of the ArduinoBLE examples together with a generic BLE app?

File -> Examples -> ArduinoBLE -> Peripheral -> BatteryMonitor

I use BLE Scanner by bluepixel on iOS. I believe it is available on Android as well. There are many others on both platforms.

This is the safest route to confirm everything is working and you know what you need to do. Then you can try your own sketch with a generic BLE app and then add your own app.

Ok yeah thats a good idea, I'll give it a try :+1: