Android -> Audio & Serial data -> Bluetooth -> Arduino

Hello there!
Since this is my first post, I will shortly introduce myself.
My name is Alex, I’m 23 and I really love ARDUINO & PROGRAMMING! :open_mouth:

This is not my first time working with arduino and other electronic components, but I’ve never used Bluetooth.
I apologize for my English (I’m from Romania :grinning: ).
So let’s get to the point.

My project is quite complex. It started from a home automation system using voice recognition in VB.Net, but now I will modify it to make a “smart room” for my girlfriend.

The idea is that an application running on Android and/or Windows will control some appliances and other components (relays, lights, LEDs, sensors) via BLUETOOTH. And that’s where I got stuck.
I watched this tutorial, and it’s pretty simple. But that’s just a start.

The most of the work is already done. I wrote the Windows app in, the Android app is in progress, the relays and ICs and shift registers and LEDs strips and sensors are working.
So all that I have left to do is to send my data commands using Bluetooth.


I want to send audio from the music player or YouTube to the Bluetooth module, but in the same time I need to send some Serial data (strings) to the Bluetooth module so that Arduino can read it and control other components.

I don’t want to use two BT modules. The idea is having one single Bluetooth module handling the connection.
For example, I want to merge this basic BT project with this audio BT project. USING ONE SINGLE Bluetooth module.
Basically, it should turn out to be something like this (is the Fiestable app for Sony audio systems…

Additionally, I attached a photo with my project, explaining how it should work.

So, any ideas?

Hey Alex,

I think what you are saying is technically possible even though I havent tried it myself. But I am sure you cant do this with the cheap HC-05s out there. As far as I know, they only support the SPP profile. So you would need a bluetooth module that supports an audio streaming profile aswell, like A2DP or AVRCP profiles.

Something like this:

In the above module you can set both the SPP and A2DP profiles discoverable before making the connection and on successesful pairing you should have an audio and serial channel simultaneously.