Microchip Bluetooth Audio
Microchip offers several solutions for Bluetooth® Audio, Voice, and Data: Wireless Audio Streaming as well as Wireless Data which are as follows:
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The BM64 stereo audio module which is a fully-certified Bluetooth Version 4.2 (BDR/EDR/BLE) module provides designers the capability Bluetooth wireless audio and voice applications to their products. Additional information on the Microchip BM64 Module is available at the following link: Microchip BM64 Module.
For Option #2, the following is an overview of the Bluetooth Stack running on the PIC32 as well as the different profiles included.Different Profiles included as well as HCI Modules are available from Microchip.
The PIC32 Basic Bluetooth Audio Package for Harmony is available for purchase on Microchip Direct, SW320024-1HPM.
Hands-Free Profile, or HFP, is a common profile used to allow a hands-free car kit or speaker system to connect to a phone source. In addition to the features found in the Headset profile, HFP adds last number redial, call waiting and voice dialing.
Support for the HFP is available for the BM64 Bluetooth Module which is included with the PIC32 Basic Bluetooth Audio Package for Harmony and is available for purchase on Microchip Direct, SW320024-1HPM.
The Advanced Audio Distribution Profile (A2DP) defines the protocols and procedures that realize distribution of audio content of high-quality in mono or stereo channels over Bluetooth. A typical usage case is wirelessly streaming music from a stereo music player to headphones or speakers. The audio data is compressed in an appropriate format for efficient use of the limited bandwidth. A2DP includes mandatory support for Low Complexity Subband Coding (SBC) of an audio stream, but can also support MPEG-1, MPEG-2, MPEG-4 and AAC codecs. MP3 audio is the more common reference to the MPEG-1 Part 3 audio compression standard.
The A/V Remote Control Profile defines the requirements for Bluetooth devices necessary for the support of the remote control options and track metadata access. This profile is designed to provide a standard interface to control Bluetooth sound docks, headphones, TVs and other devices, and to allow a single remote to control all of the Bluetooth-enabled A/V equipment. For example, it is used for providing audio controls such as play, pause, skip forward, skip backward, fast forward and rewind. PIC32 MCUs now supports AVRCP version 1.5, which includes provisions for bi-directional volume control.
The A2DP/AVRCP is available without royalty when using the BM64 Bluetooth Module. For use with and HCI Module, A2DP/AVRCP is included in the PIC32 Basic Bluetooth Audio Package for Harmony which is available for purchase on Microchip Direct, SW320024-1HPM.
Demos for Bluetooth Audio
The following are the application demos for PIC32 Digital Audio Bluetooth® Applications which include Audio, Voice, and Data.
MPLAB® Harmony Supported Demonstrations:
- BM64_a2dp_hfp: This demo is used in conjunction with the BM64 Module daughter board to demonstrate Bluetooth Audio and the Hands-Free Protocol (HFP.)
- BM64_ble_comm: This demo demonstrates data using the BM64 Module daughter board for BLE data.
- BM64_bootloader: This demo is used with the BM64 Module daughter card which appears as a virtual com port to implement a bootloader.
- ble_rn4871_comm: This demo is used to connect to the RN4871 BLE Radio to set up the radio with broadcast name, setting of public and private services, and the data for these services.
- data_basic: This demonstration performs full duplex data transfer over a Bluetooth connection using the SPP profile.
- data_temp_sens_rgb: This demonstration performs full duplex data transfer over a Bluetooth connection using the SPP profile. Command are entered on a smart phone to change the color of a RGB LED on the Bluetooth Starter Kit.
- a2dp_avrcp: This demonstration performs streaming of wireless Bluetooth audio from any smartphone (i.e., Apple, Samsung, Google, etc.), personal computer, or Bluetooth-enabled device. The demonstration supports the following features: A2DP, AVRCP, SSP, and SBC Decoder.
For more information on MPLAB® Harmony, please click on the following link: MPLAB Harmony Integrated Software Framework.
MFI Support only to Apple Licensees
If MFi Is required, the device requires a iAP/MFi software component and special hardware acquired through the Apple MFi program. For more information about the required hardware, contact email@example.com. To obtain software for this and other Microchip hardware, which is enabled for Apple products, contact your Microchip sales office. PIC32 currently supports:
- MFi data (Bluetooth): this uses L2CAP data transfer to enable data to Apple Product using Bluetooth classic similar to SPP.
- MFi data (USB): this is new for MPLAB Harmony v2.05 and enables bulk data transfer over USB to an Apple Product.
- MFi audio (USB): this allows audio streaming in handset host mode. Note this requires a custom cable assembly.