Telephone and Media Audio Profile (TMAP) Peripheral

Overview

Application demonstrating the TMAP peripheral functionality. Implements the Call Terminal (CT) and Unicast Media Receiver (UMR) roles. Either role can be built on its own: disable CONFIG_TMAP_PERIPHERAL_ROLE_CT for a media-only peripheral or CONFIG_TMAP_PERIPHERAL_ROLE_UMR for a call-only peripheral.

Requirements

A board with Bluetooth Low Energy 5.2 support

Building and Running

Build and flash the sample as follows, replacing <board> with your target board (e.g. nRF5340 DK):

west build -b <board> samples/bluetooth/audio/tmap_peripheral
west flash

After flashing, the sample initializes the TMAP Call Terminal (CT) and Unicast Media Receiver (UMR) roles, then starts advertising as TMAP Peripheral. After a TMAP Central connects and security is established, the sample discovers the peer’s TMAP role: if the peer is a Call Gateway (CG), it sends an “originate call” request and terminates it after 2 seconds; if the peer is a Unicast Media Sender (UMS), it sends a “play media” request and pauses after 2 seconds.

This automatic control demo runs only when CONFIG_TMAP_PERIPHERAL_AUTO_CTRL is enabled (the default). Disable it to keep the peripheral a passive sink that waits for the Central to drive call and media control.

Use the Telephone and Media Audio Profile (TMAP) Central sample on another board to act as the TMAP Central (CG and UMS roles).

Playback to an audio codec

The sample can decode LC3 audio and play it out to a hardware codec over I2S. Playback is optional: when the required devicetree nodes or Kconfig symbols are absent, audio_playback.c is left out of the build and the sample’s IS_ENABLED(CONFIG_SAMPLE_BT_AUDIO_PLAYBACK)-guarded calls compile away, so the sample still runs as a UMR that acknowledges the stream but discards the audio.

To enable playback on a new board, provide the following in a board overlay (or board .dts):

an i2s-codec-tx DT alias pointing at the I2S peripheral wired to the codec
a devicetree node labelled audio_codec implementing the Zephyr Audio Codec

and add a matching board .conf under boards/ enabling:

CONFIG_LIBLC3=y
CONFIG_FPU=y
CONFIG_I2S=y
CONFIG_AUDIO=y
CONFIG_AUDIO_CODEC=y

The shared playback helper (CONFIG_SAMPLE_BT_AUDIO_PLAYBACK) is enabled automatically once those dependencies are met.

On boards without an audio codec, the LC3 decode path can still be exercised by setting CONFIG_LIBLC3=y, CONFIG_FPU=y, CONFIG_SAMPLE_BT_AUDIO_PLAYBACK=y and CONFIG_SAMPLE_BT_AUDIO_PLAYBACK_SINK_NONE=y. The audio is then decoded and the resulting PCM discarded.

For interoperability with commercial smartphone LE Audio sources, you may also set CONFIG_TMAP_PERIPHERAL_STEREO=y (advertise a stereo speaker location) and CONFIG_TMAP_PERIPHERAL_AUTO_CTRL=n (stay a passive sink instead of running the CT/MCC control demo after discovery) in your board .conf or in prj.conf.

When the peer adjusts volume through the Volume Control Service (VCS), the sample maps the 0..255 VCS volume linearly onto the codec output volume and applies mute. Codec volume registers are device-specific, so set CONFIG_SAMPLE_BT_AUDIO_PLAYBACK_CODEC_VOL_MIN and CONFIG_SAMPLE_BT_AUDIO_PLAYBACK_CODEC_VOL_MAX to your codec’s range in the board .conf (for example 0 and 127 for the WM8962 register).

See Bluetooth samples for details.

Telephone and Media Audio Profile (TMAP) Peripheral

Overview

Requirements

Building and Running

Playback to an audio codec

See also