RE: Proper configuration for multi-sync PAwR with PAST and connectable advertising

Gear — Fri, 20 Jun 2025 14:10:48 GMT

Hi Dejan,

Thanks for your response and questions. Here are more details about my testing and the issue encountered:

Test Setup:

The device acts as a PAwR observer and syncs with up to 4 periodic advertisers.
It also starts a connectable extended advertiser to allow PAST procedures (sync transfer) from other devices.

Kconfig settings:

CONFIG_BT_PER_ADV_SYNC_MAX=4
CONFIG_BT_MAX_CONN was tested with 4, 8, and now 20.

Behavior Observed:

With CONFIG_BT_MAX_CONN=4, after syncing with 3 periodic advertisers, the device cannot start a connectable advertiser.
Increasing CONFIG_BT_MAX_CONN=8 allows connectable advertising to start after syncing with 3 periodic advertisers.
With CONFIG_BT_MAX_CONN=20, the device can re-sync with all 4 periodic advertisers as expected and can handle repeated sync/terminate cycles more reliably.

Implementation logic:

When a connection is established, the device stops advertising. I explicitly restart connectable advertising after connection (if total connections are below CONFIG_BT_MAX_CONN and total periodic syncs are below CONFIG_BT_PER_ADV_SYNC_MAX).
On disconnection, connectable advertising is restarted under the same condition.
When a sync is terminated, connectable advertising is also restarted to allow new syncs.
With this logic, I am able to sync to 4 devices and transfer PAST as expected.

Remaining issue:

If I power off all periodic advertisers (4 devices) and wait for the sync terminated callbacks, then power on all 4 again and wait for the device to resync, repeating this 3-4 times, eventually I encounter this error:

[00:00:49.079,345] <wrn> bt_hci_core: opcode 0x2039 status 0x0d 
[00:00:49.079,345] <err> bt_adv: Failed to start advertiser
[00:00:49.079,376] <err> main_app: Failed to start extended advertising (err -12)

So my questions are:

What is the minimal and correct set of Kconfig options (and memory/resource tuning) required for this use case?
Are there other controller/stack resources I should adjust (besides CONFIG_BT_MAX_CONN and CONFIG_BT_PER_ADV_SYNC_MAX) to support stable multi-sync and connectable advertising with repeated sync/terminate cycles?
Is there a recommended pattern for re-advertising in this kind of multi-role (PAwR observer + connectable advertiser) scenario to avoid the err -12?

For your reference, here is my latest prj.conf:

CONFIG_BT=y
CONFIG_BT_OBSERVER=y
CONFIG_BT_BROADCASTER=y
CONFIG_BT_EXT_ADV=y
CONFIG_BT_PER_ADV_SYNC=y
CONFIG_BT_PER_ADV_SYNC_MAX=4
CONFIG_BT_DEVICE_NAME="PAwR sync sample"

CONFIG_BT_MAX_CONN=20
CONFIG_BT_PERIPHERAL=y
CONFIG_BT_PER_ADV_SYNC_TRANSFER_SENDER=y
CONFIG_BT_PER_ADV_SYNC_TRANSFER_RECEIVER=y

CONFIG_BT_PER_ADV_SYNC_RSP=y
CONFIG_BT_PER_ADV_SYNC_BUF_SIZE=247

CONFIG_LOG=y

CONFIG_DW3000=y
CONFIG_DW3000_CHIP_DW3000=y
CONFIG_SPI=y
CONFIG_SPI_ASYNC=y
CONFIG_GPIO=y

CONFIG_FLASH=y
CONFIG_SPI_NOR=y
CONFIG_CBPRINTF_FP_SUPPORT=y
CONFIG_DK_LIBRARY=y

CONFIG_HEAP_MEM_POOL_SIZE=8192
CONFIG_MAIN_STACK_SIZE=2048
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=4096
CONFIG_BT_RX_STACK_SIZE=4096
CONFIG_BT_CTLR_ADV_EXT=y

And below is the full log captured during the test:

*** Booting nRF Connect SDK v3.0.0-3bfc46578e42 ***
*** Using Zephyr OS v4.0.99-a0e545cb437a ***
[00:00:00.000,640] <inf> main_app: EUI64: 511DC6CA2C7AEC34
[00:00:00.000,671] <inf> dw3000: RESET on gpio@50000000 pin 25
[00:00:00.000,701] <inf> dw3000: DW3000 SPI (max 32MHz)
[00:00:00.003,936] <inf> dw3000: IRQ on gpio@50000300 pin 2
[00:00:00.003,967] <inf> dw3000: WAKEUP CS
[00:00:00.005,157] <inf> dw3000_utils: Antenna Delay TX 16465, RX 16465
[00:00:00.012,054] <inf> main_app: DW3000_ret: 0
[00:00:00.012,634] <inf> main_app: Starting Periodic Advertising with Responses Synchronization Demo
[00:00:00.012,695] <inf> bt_sdc_hci_driver: SoftDevice Controller build revision: 
                                            c7 53 7d bc 06 12 f7 c0  b3 3a 3e 28 8e 56 1e d7 |.S}..... .:>(.V..
                                            a0 be 95 b0                                      |....             
[00:00:00.015,472] <inf> bt_hci_core: HW Platform: Nordic Semiconductor (0x0002)
[00:00:00.015,472] <inf> bt_hci_core: HW Variant: nRF52x (0x0002)
[00:00:00.015,502] <inf> bt_hci_core: Firmware: Standard Bluetooth controller (0x00) Version 199.32083 Build 4145153724
[00:00:00.016,418] <inf> bt_hci_core: Identity: F9:F5:35:3A:93:5C (random)
[00:00:00.016,448] <inf> bt_hci_core: HCI: version 6.0 (0x0e) revision 0x10e8, manufacturer 0x0059
[00:00:00.016,479] <inf> bt_hci_core: LMP: version 6.0 (0x0e) subver 0x10e8
[00:00:00.016,693] <inf> main_app: Adv start called 0 times
[00:00:00.016,693] <inf> main_app: Advertise as connectable
[00:00:00.017,852] <inf> main_app: Advertise start success
[00:00:09.158,660] <inf> main_app: Connected, err 0x00 
[00:00:09.159,088] <inf> main_app: Adv start called 1 times
[00:00:09.159,088] <inf> main_app: Advertise as connectable
[00:00:09.159,729] <inf> main_app: Advertise start success
[00:00:09.173,431] <inf> main_app: Connected, err 0x00 
[00:00:09.173,889] <inf> main_app: Adv start called 2 times
[00:00:09.173,889] <inf> main_app: Advertise as connectable
[00:00:09.174,560] <inf> main_app: Advertise start success
[00:00:09.285,644] <inf> main_app: Connected, err 0x00 
[00:00:09.286,071] <inf> main_app: Adv start called 3 times
[00:00:09.286,071] <inf> main_app: Advertise as connectable
[00:00:09.286,712] <inf> main_app: Advertise start success
[00:00:09.295,532] <inf> main_app: Connected, err 0x00 
[00:00:09.295,959] <inf> main_app: Adv start called 4 times
[00:00:09.295,989] <inf> main_app: Advertise as non-connectable
[00:00:09.296,783] <inf> main_app: Advertise start success
[00:00:09.669,036] <inf> main_app: Synced to 33:78:D7:50:9B:21 (random) with 25 subevents
[00:00:09.669,372] <inf> main_app: Changed sync 0 to subevent 0
[00:00:09.675,415] <inf> main_app: Synced to 0C:D2:DB:61:37:68 (random) with 25 subevents
[00:00:09.675,628] <inf> main_app: Changed sync 1 to subevent 0
[00:00:09.819,915] <inf> peer_forklift_manager: allocate_times 1
[00:00:09.819,976] <inf> peer_forklift_manager: Marked Forklift 9848800670EBF9ED as PAwR-synced (subevent 5)
[00:00:09.876,434] <inf> peer_forklift_manager: allocate_times 2
[00:00:09.876,495] <inf> peer_forklift_manager: Marked Forklift 3306911FAB19632F as PAwR-synced (subevent 5)
[00:00:09.917,816] <inf> main_app: Synced to 0B:24:AF:FF:C4:FC (random) with 25 subevents
[00:00:09.918,151] <inf> main_app: Changed sync 2 to subevent 0
[00:00:09.923,278] <inf> main_app: Synced to 1A:ED:28:61:72:64 (random) with 25 subevents
[00:00:09.923,492] <inf> main_app: Changed sync 3 to subevent 0
[00:00:10.068,695] <inf> peer_forklift_manager: allocate_times 3
[00:00:10.068,756] <inf> peer_forklift_manager: Marked Forklift 824CD893202B3DA4 as PAwR-synced (subevent 5)
[00:00:10.074,218] <inf> peer_forklift_manager: allocate_times 4
[00:00:10.074,249] <inf> peer_forklift_manager: Marked Forklift BD39639676698672 as PAwR-synced (subevent 5)
[00:00:10.420,135] <inf> main_app: disconnected conn: 3 synced (4/4 used)
[00:00:10.420,196] <inf> main_app: Disconnected, reason 0x13 
[00:00:10.420,227] <inf> main_app: Adv start called 5 times
[00:00:10.420,410] <inf> main_app: Advertise as non-connectable
[00:00:10.421,234] <inf> main_app: Advertise start success
[00:00:10.477,020] <inf> main_app: disconnected conn: 2 synced (4/4 used)
[00:00:10.477,081] <inf> main_app: Disconnected, reason 0x13 
[00:00:10.477,111] <inf> main_app: Adv start called 6 times
[00:00:10.477,294] <inf> main_app: Advertise as non-connectable
[00:00:10.478,057] <inf> main_app: Advertise start success
[00:00:10.624,450] <inf> main_app: disconnected conn: 1 synced (4/4 used)
[00:00:10.624,481] <inf> main_app: Disconnected, reason 0x13 
[00:00:10.624,511] <inf> main_app: Adv start called 7 times
[00:00:10.624,694] <inf> main_app: Advertise as non-connectable
[00:00:10.625,488] <inf> main_app: Advertise start success
[00:00:10.769,378] <inf> main_app: disconnected conn: 0 synced (4/4 used)
[00:00:10.769,439] <inf> main_app: Disconnected, reason 0x13 
[00:00:10.769,439] <inf> main_app: Adv start called 8 times
[00:00:10.769,653] <inf> main_app: Advertise as non-connectable
[00:00:10.770,446] <inf> main_app: Advertise start success
[00:00:12.168,762] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 0
[00:00:12.169,006] <inf> main_app: Changed sync 0 to subevent 5
[00:00:12.175,354] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 0
[00:00:12.175,567] <inf> main_app: Changed sync 1 to subevent 5
[00:00:12.423,034] <inf> main_app: Indication from BD39639676698672, sync 3, subevent 0
[00:00:12.423,248] <inf> main_app: Changed sync 3 to subevent 5
[00:00:12.968,688] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:12.975,402] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:13.167,724] <inf> main_app: Indication from 824CD893202B3DA4, sync 2, subevent 0
[00:00:13.168,060] <inf> main_app: Changed sync 2 to subevent 5
[00:00:13.223,022] <inf> main_app: Indication from BD39639676698672, sync 3, subevent 5
[00:00:13.967,834] <inf> main_app: Indication from 824CD893202B3DA4, sync 2, subevent 5
[00:00:13.975,463] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:14.222,991] <inf> main_app: Indication from BD39639676698672, sync 3, subevent 5
[00:00:14.967,895] <inf> main_app: Indication from 824CD893202B3DA4, sync 2, subevent 5
[00:00:14.975,524] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:15.222,961] <inf> main_app: Indication from BD39639676698672, sync 3, subevent 5
[00:00:15.967,956] <inf> main_app: Indication from 824CD893202B3DA4, sync 2, subevent 5
[00:00:15.975,585] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:16.222,961] <inf> main_app: Indication from BD39639676698672, sync 3, subevent 5
[00:00:16.968,017] <inf> main_app: Indication from 824CD893202B3DA4, sync 2, subevent 5
[00:00:16.975,646] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:17.222,930] <inf> main_app: Indication from BD39639676698672, sync 3, subevent 5
[00:00:17.467,926] <inf> main_app: Received empty indication: sync 2 subevent 5
[00:00:17.468,078] <inf> main_app: Sync terminated (reason 31)
[00:00:17.468,139] <inf> main_app: Adv start called 9 times
[00:00:17.468,292] <inf> main_app: Advertise as connectable
[00:00:17.468,994] <inf> main_app: Advertise start success
[00:00:17.472,808] <inf> main_app: Received empty indication: sync 3 subevent 5
[00:00:17.475,524] <inf> main_app: Received empty indication: sync 1 subevent 5
[00:00:17.718,536] <inf> main_app: Received empty indication: sync 0 subevent 5
[00:00:17.718,688] <inf> main_app: Sync terminated (reason 31)
[00:00:17.718,750] <inf> main_app: Adv start called 10 times
[00:00:17.718,933] <inf> main_app: Advertise as connectable
[00:00:17.719,635] <inf> main_app: Advertise start success
[00:00:17.722,900] <inf> main_app: Received empty indication: sync 3 subevent 5
[00:00:17.723,052] <inf> main_app: Sync terminated (reason 31)
[00:00:17.723,083] <inf> main_app: Adv start called 11 times
[00:00:17.723,297] <inf> main_app: Advertise as connectable
[00:00:17.723,907] <inf> main_app: Advertise start success
[00:00:17.725,646] <inf> main_app: Received empty indication: sync 1 subevent 5
[00:00:17.725,769] <inf> main_app: Sync terminated (reason 31)
[00:00:17.725,799] <inf> main_app: Adv start called 12 times
[00:00:17.726,013] <inf> main_app: Advertise as connectable
[00:00:17.726,654] <inf> main_app: Advertise start success
[00:00:18.000,640] <inf> peer_forklift_manager: removed_times 1
[00:00:22.000,640] <inf> peer_forklift_manager: removed_times 2
[00:00:22.000,671] <inf> peer_forklift_manager: removed_times 3
[00:00:22.250,640] <inf> peer_forklift_manager: removed_times 4
[00:00:28.138,916] <inf> main_app: Connected, err 0x00 
[00:00:28.139,343] <inf> main_app: Adv start called 13 times
[00:00:28.139,343] <inf> main_app: Advertise as connectable
[00:00:28.140,014] <inf> main_app: Advertise start success
[00:00:28.153,991] <inf> main_app: Connected, err 0x00 
[00:00:28.154,449] <inf> main_app: Adv start called 14 times
[00:00:28.154,449] <inf> main_app: Advertise as connectable
[00:00:28.155,120] <inf> main_app: Advertise start success
[00:00:28.267,395] <inf> main_app: Connected, err 0x00 
[00:00:28.267,822] <inf> main_app: Adv start called 15 times
[00:00:28.267,852] <inf> main_app: Advertise as connectable
[00:00:28.268,524] <inf> main_app: Advertise start success
[00:00:28.380,187] <inf> main_app: Connected, err 0x00 
[00:00:28.380,645] <inf> main_app: Adv start called 16 times
[00:00:28.380,645] <inf> main_app: Advertise as non-connectable
[00:00:28.381,439] <inf> main_app: Advertise start success
[00:00:28.494,659] <inf> main_app: Synced to 18:B3:57:A3:EB:6B (random) with 25 subevents
[00:00:28.494,903] <inf> main_app: Changed sync 0 to subevent 0
[00:00:28.508,422] <inf> main_app: Synced to 32:D5:8F:42:67:A8 (random) with 25 subevents
[00:00:28.508,666] <inf> main_app: Changed sync 1 to subevent 0
[00:00:28.695,709] <inf> peer_forklift_manager: allocate_times 5
[00:00:28.695,770] <inf> peer_forklift_manager: Marked Forklift 9848800670EBF9ED as PAwR-synced (subevent 5)
[00:00:28.709,472] <inf> peer_forklift_manager: allocate_times 6
[00:00:28.709,533] <inf> peer_forklift_manager: Marked Forklift 3306911FAB19632F as PAwR-synced (subevent 5)
[00:00:28.747,802] <inf> main_app: Synced to 03:AE:6A:B9:76:17 (random) with 25 subevents
[00:00:28.748,046] <inf> main_app: Changed sync 2 to subevent 0
[00:00:28.769,317] <inf> main_app: Synced to 20:FD:7A:BD:DC:B4 (random) with 25 subevents
[00:00:28.769,561] <inf> main_app: Changed sync 3 to subevent 0
[00:00:28.820,251] <inf> peer_forklift_manager: allocate_times 7
[00:00:28.820,312] <inf> peer_forklift_manager: Marked Forklift 824CD893202B3DA4 as PAwR-synced (subevent 5)
[00:00:29.048,767] <inf> peer_forklift_manager: allocate_times 8
[00:00:29.048,828] <inf> peer_forklift_manager: Marked Forklift BD39639676698672 as PAwR-synced (subevent 5)
[00:00:29.296,234] <inf> main_app: disconnected conn: 3 synced (4/4 used)
[00:00:29.296,295] <inf> main_app: Disconnected, reason 0x13 
[00:00:29.296,325] <inf> main_app: Adv start called 17 times
[00:00:29.296,508] <inf> main_app: Advertise as non-connectable
[00:00:29.297,332] <inf> main_app: Advertise start success
[00:00:29.359,558] <inf> main_app: disconnected conn: 2 synced (4/4 used)
[00:00:29.359,619] <inf> main_app: Disconnected, reason 0x13 
[00:00:29.359,649] <inf> main_app: Adv start called 18 times
[00:00:29.359,832] <inf> main_app: Advertise as non-connectable
[00:00:29.360,626] <inf> main_app: Advertise start success
[00:00:29.370,422] <inf> main_app: disconnected conn: 1 synced (4/4 used)
[00:00:29.370,452] <inf> main_app: Disconnected, reason 0x13 
[00:00:29.370,483] <inf> main_app: Adv start called 19 times
[00:00:29.370,666] <inf> main_app: Advertise as non-connectable
[00:00:29.371,459] <inf> main_app: Advertise start success
[00:00:29.598,876] <inf> main_app: disconnected conn: 0 synced (4/4 used)
[00:00:29.598,937] <inf> main_app: Disconnected, reason 0x13 
[00:00:29.598,968] <inf> main_app: Adv start called 20 times
[00:00:29.599,151] <inf> main_app: Advertise as non-connectable
[00:00:29.599,945] <inf> main_app: Advertise start success
[00:00:31.258,392] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 0
[00:00:31.258,636] <inf> main_app: Changed sync 1 to subevent 5
[00:00:31.269,256] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 0
[00:00:31.269,500] <inf> main_app: Changed sync 3 to subevent 5
[00:00:31.494,415] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 0
[00:00:31.494,628] <inf> main_app: Changed sync 0 to subevent 5
[00:00:31.497,558] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 0
[00:00:31.497,772] <inf> main_app: Changed sync 2 to subevent 5
[00:00:31.547,576] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:32.058,441] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:32.294,403] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:32.319,335] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 5
[00:00:32.544,403] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:32.547,546] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:32.797,546] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:33.058,502] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:33.294,372] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:33.319,396] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 5
[00:00:33.544,372] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:33.547,515] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:33.797,515] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:34.058,563] <inf> main_app: Indication from 3306911FAB19632F, sync 1, subevent 5
[00:00:34.294,342] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:34.319,427] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 5
[00:00:34.544,342] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:34.547,515] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:34.797,515] <inf> main_app: Indication from BD39639676698672, sync 2, subevent 5
[00:00:35.044,219] <inf> main_app: Received empty indication: sync 0 subevent 5
[00:00:35.047,393] <inf> main_app: Received empty indication: sync 2 subevent 5
[00:00:35.058,502] <inf> main_app: Received empty indication: sync 1 subevent 5
[00:00:35.069,366] <inf> main_app: Received empty indication: sync 3 subevent 5
[00:00:35.294,311] <inf> main_app: Received empty indication: sync 0 subevent 5
[00:00:35.294,433] <inf> main_app: Sync terminated (reason 31)
[00:00:35.294,494] <inf> main_app: Adv start called 21 times
[00:00:35.294,677] <inf> main_app: Advertise as connectable
[00:00:35.295,349] <inf> main_app: Advertise start success
[00:00:35.297,485] <inf> main_app: Received empty indication: sync 2 subevent 5
[00:00:35.297,607] <inf> main_app: Sync terminated (reason 31)
[00:00:35.297,668] <inf> main_app: Adv start called 22 times
[00:00:35.297,851] <inf> main_app: Advertise as connectable
[00:00:35.298,522] <inf> main_app: Advertise start success
[00:00:35.308,563] <inf> main_app: Received empty indication: sync 1 subevent 5
[00:00:35.308,715] <inf> main_app: Sync terminated (reason 31)
[00:00:35.308,776] <inf> main_app: Adv start called 23 times
[00:00:35.308,990] <inf> main_app: Advertise as connectable
[00:00:35.309,661] <inf> main_app: Advertise start success
[00:00:35.319,458] <inf> main_app: Received empty indication: sync 3 subevent 5
[00:00:35.319,580] <inf> main_app: Sync terminated (reason 31)
[00:00:35.319,610] <inf> main_app: Adv start called 24 times
[00:00:35.319,824] <inf> main_app: Advertise as connectable
[00:00:35.320,495] <inf> main_app: Advertise start success
[00:00:39.125,640] <inf> peer_forklift_manager: removed_times 5
[00:00:39.375,640] <inf> peer_forklift_manager: removed_times 6
[00:00:39.625,640] <inf> peer_forklift_manager: removed_times 7
[00:00:39.875,640] <inf> peer_forklift_manager: removed_times 8
[00:00:41.807,952] <inf> main_app: Connected, err 0x00 
[00:00:41.808,380] <inf> main_app: Adv start called 25 times
[00:00:41.808,410] <inf> main_app: Advertise as connectable
[00:00:41.809,051] <inf> main_app: Advertise start success
[00:00:42.035,278] <inf> main_app: Connected, err 0x00 
[00:00:42.035,705] <inf> main_app: Adv start called 26 times
[00:00:42.035,705] <inf> main_app: Advertise as connectable
[00:00:42.036,376] <inf> main_app: Advertise start success
[00:00:42.045,745] <inf> main_app: Connected, err 0x00 
[00:00:42.046,142] <inf> main_app: Adv start called 27 times
[00:00:42.046,173] <inf> main_app: Advertise as connectable
[00:00:42.046,813] <inf> main_app: Advertise start success
[00:00:42.162,780] <inf> main_app: Connected, err 0x00 
[00:00:42.163,208] <inf> main_app: Adv start called 28 times
[00:00:42.163,238] <inf> main_app: Advertise as non-connectable
[00:00:42.164,031] <inf> main_app: Advertise start success
[00:00:42.292,083] <inf> main_app: Synced to 17:A7:1D:C3:93:A7 (random) with 25 subevents
[00:00:42.292,327] <inf> main_app: Changed sync 0 to subevent 0
[00:00:42.393,035] <inf> peer_forklift_manager: allocate_times 9
[00:00:42.393,096] <inf> peer_forklift_manager: Marked Forklift 9848800670EBF9ED as PAwR-synced (subevent 5)
[00:00:42.528,747] <inf> main_app: Synced to 0D:76:63:96:8E:7E (random) with 25 subevents
[00:00:42.528,991] <inf> main_app: Changed sync 1 to subevent 0
[00:00:42.546,722] <inf> main_app: Synced to 16:F5:E7:53:EB:CA (random) with 25 subevents
[00:00:42.546,966] <inf> main_app: Changed sync 2 to subevent 0
[00:00:42.557,067] <inf> main_app: Synced to 09:35:81:42:1F:39 (random) with 25 subevents
[00:00:42.557,281] <inf> main_app: Changed sync 3 to subevent 0
[00:00:42.608,001] <inf> peer_forklift_manager: allocate_times 10
[00:00:42.608,032] <inf> peer_forklift_manager: Marked Forklift 824CD893202B3DA4 as PAwR-synced (subevent 5)
[00:00:42.679,687] <inf> peer_forklift_manager: allocate_times 11
[00:00:42.679,748] <inf> peer_forklift_manager: Marked Forklift BD39639676698672 as PAwR-synced (subevent 5)
[00:00:42.847,778] <inf> peer_forklift_manager: allocate_times 12
[00:00:42.847,839] <inf> peer_forklift_manager: Marked Forklift 3306911FAB19632F as PAwR-synced (subevent 5)
[00:00:42.943,145] <inf> main_app: disconnected conn: 3 synced (4/4 used)
[00:00:42.943,206] <inf> main_app: Disconnected, reason 0x13 
[00:00:42.943,237] <inf> main_app: Adv start called 29 times
[00:00:42.943,420] <inf> main_app: Advertise as non-connectable
[00:00:42.944,183] <inf> main_app: Advertise start success
[00:00:43.208,160] <inf> main_app: disconnected conn: 2 synced (4/4 used)
[00:00:43.208,190] <inf> main_app: Disconnected, reason 0x13 
[00:00:43.208,221] <inf> main_app: Adv start called 30 times
[00:00:43.208,404] <inf> main_app: Advertise as non-connectable
[00:00:43.209,197] <inf> main_app: Advertise start success
[00:00:43.229,797] <inf> main_app: disconnected conn: 1 synced (4/4 used)
[00:00:43.229,858] <inf> main_app: Disconnected, reason 0x13 
[00:00:43.229,888] <inf> main_app: Adv start called 31 times
[00:00:43.230,072] <inf> main_app: Advertise as non-connectable
[00:00:43.230,865] <inf> main_app: Advertise start success
[00:00:43.497,863] <inf> main_app: disconnected conn: 0 synced (4/4 used)
[00:00:43.497,894] <inf> main_app: Disconnected, reason 0x13 
[00:00:43.497,924] <inf> main_app: Adv start called 32 times
[00:00:43.498,107] <inf> main_app: Advertise as non-connectable
[00:00:43.498,901] <inf> main_app: Advertise start success
[00:00:44.778,503] <inf> main_app: Indication from BD39639676698672, sync 1, subevent 0
[00:00:44.778,747] <inf> main_app: Changed sync 1 to subevent 5
[00:00:44.791,839] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 0
[00:00:44.792,053] <inf> main_app: Changed sync 0 to subevent 5
[00:00:44.796,661] <inf> main_app: Indication from 3306911FAB19632F, sync 2, subevent 0
[00:00:44.796,875] <inf> main_app: Changed sync 2 to subevent 5
[00:00:45.056,976] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 0
[00:00:45.057,220] <inf> main_app: Changed sync 3 to subevent 5
[00:00:45.091,827] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:45.328,491] <inf> main_app: Indication from BD39639676698672, sync 1, subevent 5
[00:00:45.596,710] <inf> main_app: Indication from 3306911FAB19632F, sync 2, subevent 5
[00:00:45.841,796] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:45.857,025] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 5
[00:00:46.078,491] <inf> main_app: Indication from BD39639676698672, sync 1, subevent 5
[00:00:46.596,771] <inf> main_app: Indication from 3306911FAB19632F, sync 2, subevent 5
[00:00:46.828,460] <inf> main_app: Indication from BD39639676698672, sync 1, subevent 5
[00:00:46.841,796] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:46.857,086] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 5
[00:00:47.078,460] <inf> main_app: Indication from BD39639676698672, sync 1, subevent 5
[00:00:47.596,832] <inf> main_app: Indication from 3306911FAB19632F, sync 2, subevent 5
[00:00:47.841,766] <inf> main_app: Indication from 9848800670EBF9ED, sync 0, subevent 5
[00:00:47.857,147] <inf> main_app: Indication from 824CD893202B3DA4, sync 3, subevent 5
[00:00:48.078,460] <inf> main_app: Indication from BD39639676698672, sync 1, subevent 5
[00:00:48.596,893] <inf> main_app: Indication from 3306911FAB19632F, sync 2, subevent 5
[00:00:48.828,338] <inf> main_app: Received empty indication: sync 1 subevent 5
[00:00:48.841,613] <inf> main_app: Received empty indication: sync 0 subevent 5
[00:00:48.846,771] <inf> main_app: Received empty indication: sync 2 subevent 5
[00:00:48.857,055] <inf> main_app: Received empty indication: sync 3 subevent 5
[00:00:49.078,399] <inf> main_app: Received empty indication: sync 1 subevent 5
[00:00:49.078,552] <inf> main_app: Sync terminated (reason 31)
[00:00:49.078,582] <inf> main_app: Adv start called 33 times
[00:00:49.078,765] <inf> main_app: Advertise as connectable
[00:00:49.079,345] <wrn> bt_hci_core: opcode 0x2039 status 0x0d 
[00:00:49.079,345] <err> bt_adv: Failed to start advertiser
[00:00:49.079,376] <err> main_app: Failed to start extended advertising  (err -12)
[00:00:49.079,376] <err> main_app: Advertise start failed: need to restart (workaround solution)
[00:00:49.091,705] <inf> main_app: Received empty indication: sync 0 subevent 5
[00:00:49.091,857] <inf> main_app: Sync terminated (reason 31)
[00:00:49.096,862] <inf> main_app: Received empty indication: sync 2 subevent 5
[00:00:49.096,984] <inf> main_app: Sync terminated (reason 31)
[00:00:49.107,147] <inf> main_app: Received empty indication: sync 3 subevent 5
[00:00:49.107,269] <inf> main_app: Sync terminated (reason 31)

Best regards,

Gear

RE: Proper configuration for multi-sync PAwR with PAST and connectable advertising

dejans — Thu, 19 Jun 2025 10:13:32 GMT

Hi Gear,

Can you make a diagram of your testing setup and provide detailed information about the devices used and their roles?

[quote user=""]But if we increase CONFIG_BT_MAX_CONN = 8, we still can start connectable advertising after synced with 3 periodic advertiser.[/quote]

Does this mean that when CONFIG_BT_MAX_CONN=8, there is no error in the log, and everything works as expected (with your shown project configuration)?
Using CONFIG_BT_MAX_CONN=8, what is the maximum number of simultaneous connections in your case that do not produce an error?
Is CONFIG_BT_MAX_CONN=8 the only change between working and non-working case?

Have you made any changes to the samples?

[quote user=""]

Current configuration:

CONFIG_BT_PER_ADV_SYNC_MAX = 4
CONFIG_BT_MAX_CONN = 4 (initially)

With this setup, we can successfully sync to 3 periodic advertisers using bt_le_per_adv_sync_subevent() to subscribe to subevents.

Problem:

If CONFIG_BT_MAX_CONN = 4, we cannot start connectable advertising after success with 3 periodic synced

[/quote]

Have you tried to increase both values for CONFIG_BT_MAX_CONN and CONFIG_BT_PER_ADV_SYNC_MAX?

Best regards,
Dejan