BT Audio click

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BT Audio click
BT Audio click
IC/Module RN52
Interface UART
Power supply 3.3V
Product page
Schematic BT Audio click schematic

BT Audio click features Microchip’s RN52 Bluetooth audio module capable of streaming high quality audio. The module combines class 2 Bluetooth radio and an embedded DSP processor, controlled and configured by simple ASCII commands and GPIO. The board has two audio jacks, input (microphone) and line out (for connecting speakers).

Features and usage notes

1. BT Audio click can stream audio files

DSP, or digital signal processor, is what makes this module special, because the module can actually stream audio – it converts and compresses the radio waves sent from your phone or computer into digital data, and then sends it to your speakers or headphones.

2. Quality of sound over Bluetooth

You can be glad to know that the module supports aptX, audio codec for high quality stereo audio streaming over a Bluetooth connection. So the quality of the sound is not something you will have to compromise on, as aptX encodes a CD-quality (16-bit / 44.1kHz) audio stream.

3. Connectivity to Apple devices

The module also supports iAP profile discovery for connecting BT Audio click to Apple devices like iPods, iPhones or MAC computers.

  • The RN52 supports HSP/HFP, A2DP, AVRCP and SPP, as well as digital I/O, stereo speaker output, stereo microphone input,up to 11 General Purpose I/O’s, and 2 LED status outputs.
  • The HSP/HFP stands for Hands-Free Profile and Headset Profile for an audio connection between Bluetooth on your phone and the headset.

4. Bluetooth range

The BT Audio click has a 10m range in open space, but it might be less indoors, because of all the walls and other kinds of barriers. But it is enough range to cover your house or apartment, so you can move your phone to the kitchen without losing the connection to the speakers.

BT Audio click communicates with the target board MCU through MikroBUS UART. A green LED indicates that power is on.

The BT Audio click runs on 3.3V power supply only.

Key features

The demo is a GUI application made for the mikromedia+ for STM32F7 with a shield. The Application uses BT Audio library to interface between the touch screen and click board to play music and make phone calls.

 1 void play_btnOnClick()
 2 {
 3     connection_status_t connection;
 5     bt_audio_query_connection_status( &connection );
 6     if( !connection.A2DP_connection )
 7         return;
 8     if( music_state_t == PAUSED )
 9     {
10         bt_audio_pause_play_track();
11         music_state_t = PLAYING;
12         if( first_song )
13         {
14             get_track_data();
15             first_song = false;
16         }
17     }
18 }

The complete project is available on Libstock.

Pinout diagram

This table shows how the pinout on BT Audio click corresponds to the pinout on the mikroBUS™ socket.

Notes Pin Mikrobus logo.png


Pin Notes
Defines baud rate of module     BAUD 1 AN X PWM 16 CMD Puts module in command/data operation    
2 RST INT 15 FIRST Factory reset    
Powers up the module     POWER_EN 3 CS TX 14 RX
4 SCK RX 13 TX
+3.3V power input +3.3V 7 +3.3V +5V 10 NC This click supports 3.3V only
Ground GND 8 GND GND 9 GND Ground