This example implements the Telephony and Media Audio Profile (TMAP) Broadcast Media Receiver (BMR) role. The device scans for non-connectable extended advertisers that carry both the Broadcast Audio Announcement service (with a 24-bit broadcast ID) and the TMAS service with the BMS role bit set, then synchronizes to periodic advertising and the BIG to receive broadcast audio.

The implementation uses ESP-BLE-AUDIO for TMAP role registration, the BAP broadcast sink, the BAP scan delegator, the PACS sink (LC3 capability: 48 kHz, 10 ms, 1 channel, 100 octets/frame, media context — sized for the 48_2_1 preset that the paired BMS sends), and a VCP Volume Renderer (initial volume 10, unmuted, step 1). Up to CONFIG_BT_BAP_BROADCAST_SNK_STREAM_COUNT streams are pre-allocated and reused for every BIG sync; received SDUs are accounted for via example_audio_rx_metrics_*.

Requirements

A board with BLE 5.2, ISO, and LE Audio support (e.g. ESP32-H4, ESP32-S31)
Peer device running the paired example

Configuration

idf.py menuconfig

No build-time options — runtime defaults are baked into source.

Security & Pairing

Security is inherited from ../../common_components/example_init/ble_audio_example_init.c: LE Secure Connections with bonding enabled, no MITM, Just-Works pairing (BLE_SM_IO_CAP_NO_IO). The BMR receives broadcast (unencrypted) audio, so these settings only apply if a peer (e.g. a Broadcast Assistant) opens an ATT connection to the scan delegator / VCP renderer.

Build & Flash

The base sdkconfig.defaults defaults to the Bluedroid host; idf.py automatically merges the per-target overlay (sdkconfig.defaults.$IDF_TARGET). To build with NimBLE host instead, layer sdkconfig.defaults.nimble on top via -DSDKCONFIG_DEFAULTS.

Bluedroid host (default)

idf.py set-target esp32h4
idf.py -p PORT flash monitor

NimBLE host

idf.py set-target esp32h4
idf.py -DSDKCONFIG_DEFAULTS="sdkconfig.defaults;sdkconfig.defaults.esp32h4;sdkconfig.defaults.nimble" -p PORT flash monitor

For esp32s31, replace the chip overlay accordingly.

(Exit serial monitor with Ctrl-].)

Example Flow

Initialize NVS, the Bluetooth controller/host, and the LE Audio common layer with a GAP app callback that handles EXT_SCAN_RECV, PA_SYNC, and PA_SYNC_LOST.
Register the TMAP role as ESP_BLE_AUDIO_TMAP_ROLE_BMR, then initialize the VCP Volume Renderer (vcp_vol_renderer_init) and the BAP broadcast sink (bap_broadcast_sink_init: PACS sink + sink location, broadcast sink callbacks, LC3 sink capability, scan delegator, stream ops on each pre-allocated stream).
Start the audio stack and begin passive extended scanning at 100 ms / 100 ms with BLE_HS_FOREVER duration.
On each scan result, parse service-data: capture broadcast ID from Broadcast Audio Announcement, set tmap_bms_found when TMAS carries the BMS role; if both are present and no PA sync is in progress, create the periodic-advertising sync.
On PA_SYNC success, cancel scanning, log the sync handle, and create the broadcast sink for the sync handle and broadcast ID.
The base_recv callback extracts the BIS index bitfield masked by the available stream count; the syncable callback then calls esp_ble_audio_bap_broadcast_sink_sync with the stream pointer array.
Per-stream started callback resets RX metrics; recv callback feeds each SDU into example_audio_rx_metrics_on_recv (tracking valid/error/lost/zero-length counts); stopped logs the reason.
On PA_SYNC_LOST matching the active sync handle, delete the broadcast sink and re-enter scanning.

Expected Log

TAG is TMAP_BMR.

Init:

I (xxx) TMAP_BMR: VCP volume renderer initialized
I (xxx) TMAP_BMR: BAP broadcast sink initialized
I (xxx) TMAP_BMR: Scanning for broadcaster...

Scan and PA sync:

I (xxx) TMAP_BMR: Found TMAP BMS, starting PA sync (broadcast ID 0x......)
I (xxx) TMAP_BMR: PA synced: handle .. sid .. phy .. peer xx:xx:xx:xx:xx:xx
I (xxx) TMAP_BMR: PA sync .. synced with broadcast ID 0x......
I (xxx) TMAP_BMR: Broadcast source PA synced, waiting for BASE
I (xxx) TMAP_BMR: BASE received, creating broadcast sink

Streaming:

I (xxx) TMAP_BMR: [SNK #0] Stream started

(Subsequent per-packet metrics are emitted by example_audio_rx_metrics_on_recv under the SNK #N label.)

Stop / sync loss:

I (xxx) TMAP_BMR: [SNK #0] Stream stopped, reason 0x..
I (xxx) TMAP_BMR: PA sync lost: sync_handle .. reason 0x..
I (xxx) TMAP_BMR: PA sync .. lost with reason ..

VCP (when remote queries volume/flags):

I (xxx) TMAP_BMR: VCS volume .., mute ..
I (xxx) TMAP_BMR: VCS flags 0x..

Warnings (malformed adv):

W (xxx) TMAP_BMR: Invalid ad size .. (uuid)
W (xxx) TMAP_BMR: Invalid ad size .. (Broadcast ID)
W (xxx) TMAP_BMR: Invalid ad size .. (tmap role)

Peer Pairing

Run bms on a second board.

Flash and boot this BMR; it initializes VCP and PACS, then enters extended scanning.
Boot the BMS peer; it advertises with TMAS BMS role and broadcast ID 0x123456 plus periodic advertising carrying the BASE.
This BMR matches both service-data entries on a single scan result and creates the PA sync; on success it cancels scanning and creates the broadcast sink.
base_recv derives the BIS index bitfield, then syncable triggers esp_ble_audio_bap_broadcast_sink_sync with the pre-allocated stream pointers.
Stream started fires, RX metrics reset, and recv accumulates valid/error/lost/zero-length SDU counters as the BMS sends.
If the BMS stops or moves out of range, PA sync loss tears down the sink and the BMR resumes scanning automatically.