Hi,
Our team has encountered an intermittent issue when attempting to connect to our nRF device (nRF52833) using the nRF Connect Desktop BLE app. This issue does not occur when connecting using the nRF Connect Mobile app for both Android and iOS. Our application is using the nRF Connect SDK v2.5.1.
This error occurs as soon as the device connects, but before the BT connected callback is triggered. We have tried increasing the MPSL work queue stack size (CONFIG_MPSL_WORK_STACK_SIZE) to 8K but the issue persists. The Bluetooth logs were set to debug level but no differences were observed in them for when the error occurred or not.
Below are the relevant Kconfigs:
CONFIG_BT=y CONFIG_BT_ID_MAX=1 CONFIG_BT_PERIPHERAL=y CONFIG_BT_BAS=y CONFIG_BT_HRS=n CONFIG_BT_DEVICE_APPEARANCE=31368 CONFIG_BT_LIM_ADV_TIMEOUT=32 # seconds # BT Pairing # CONFIG_BT_MAX_CONN Has to be 2 when calling "bt_le_adv_start" from disconnected() callback CONFIG_BT_SMP=y CONFIG_BT_SMP_APP_PAIRING_ACCEPT=y CONFIG_BT_MAX_CONN=2 CONFIG_BT_MAX_PAIRED=2 CONFIG_BT_FIXED_PASSKEY=y CONFIG_BT_FILTER_ACCEPT_LIST=y # The use of RPA is not enabled CONFIG_BT_PRIVACY=n # DIS Items CONFIG_BT_DIS=y CONFIG_BT_DIS_PNP=n CONFIG_BT_DIS_HW_REV=y CONFIG_BT_DIS_HW_REV_STR="HW V1" CONFIG_BT_DIS_FW_REV=y CONFIG_BT_DIS_FW_REV_STR="FW V0.4.1" CONFIG_BT_DIS_SETTINGS=y CONFIG_BT_DIS_STR_MAX=20 # Below is setup to let DIS information be read from settings # CONFIG_SETTINGS_NONE=y # Enable BT Bonding and DIS info read from settings CONFIG_BT_SETTINGS=y CONFIG_SETTINGS=y CONFIG_SETTINGS_NVS=y CONFIG_SETTINGS_RUNTIME=y CONFIG_FLASH=y CONFIG_FLASH_PAGE_LAYOUT=y CONFIG_FLASH_MAP=y CONFIG_NVS=y CONFIG_NVS_LOG_LEVEL_DBG=y CONFIG_BT_BONDABLE=y CONFIG_BT_ID_UNPAIR_MATCHING_BONDS=y # BT size settings #CONFIG_BT_L2CAP_TX_MTU=247 #CONFIG_BT_BUF_ACL_RX_SIZE=251 #CONFIG_BT_BUF_ACL_TX_SIZE=251 #CONFIG_BT_CTLR_DATA_LENGTH_MAX=251 # Stack sizes CONFIG_MPU_STACK_GUARD=y CONFIG_BT_RX_STACK_SIZE=2048 # Note: This stack must be 2K or higher to avoid stack overflow when pairing to Android Devices CONFIG_MPSL_WORK_STACK_SIZE=2048 CONFIG_BT_HCI_TX_STACK_SIZE_WITH_PROMPT=y CONFIG_BT_HCI_TX_STACK_SIZE=1024
Here are the RTT error logs from the nRF device:
[00:00:22.271,484] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 2
[00:00:22.272,033] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.272,888] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.273,803] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.274,353] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 2
[00:00:22.274,963] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.275,787] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.276,641] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.277,252] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 16
[00:00:22.278,289] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 19
[00:00:22.279,449] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 19
[00:00:22.280,609] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 2
[00:00:22.281,219] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.282,104] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 2
[00:00:22.282,714] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.283,569] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.284,179] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.285,095] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.286,224] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 5
[00:00:22.286,743] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 16
00:22.287,628] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 19
[00:00:22.289,672] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 16
[00:00:22.290,374] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 19
[00:00:22.291,259] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 19
[00:00:22.292,175] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 16
[00:00:22.292,846] <dbg> bt_gatt: bt_gatt_attr_read: handle 0x0000 offset 0 length 19
[00:00:22.293,731] <dbg> bt_gatt: db_hash_gen: Hash:
54 6d 2d c6 e1 e6 d3 79 22 5b 9d 50 ba a9 7f 92 |Tm-....y "[.P....
[00:00:22.323,242] <dbg> bt_hci_core: bt_recv: buf 0x2001c4e0 len 68
[00:00:22.323,669] <dbg> bt_hci_core: rx_work_handler: Getting net_buf from queue
[00:00:22.324,096] <dbg> bt_hci_core: rx_work_handler: buf 0x2001c4e0 type 1 len 68
[00:00:22.324,523] <dbg> bt_hci_core: hci_event: event 0x3e
[00:00:22.324,890] <dbg> bt_hci_core: hci_le_meta_event: subevent 0x08
[00:00:22.325,256] <dbg> bt_ecc: bt_hci_evt_le_pkey_complete: status: 0x00
[00:00:22.325,653] <dbg> bt_smp: bt_smp_pkey_ready:
[00:00:25.279,876] <dbg> bt_sdc_hci_driver: event_packet_process: LE Meta Event (0x0a), len (31)
[00:00:25.280,548] <dbg> bt_hci_core: bt_recv: buf 0x2001c4e0 len 33
[00:00:25.281,158] <err> os: ***** BUS FAULT *****
[00:00:25.281,463] <err> os: Imprecise data bus error
[00:00:25.281,829] <err> os: r0/a1: 0x0014043e r1/a2: 0x2000410b r2/a3: 0x0000000a
[00:00:25.282,318] <err> os: r3/a4: 0x0014043f r12/ip: 0x00000007 r14/lr: 0x0000366b
[00:00:25.282,775] <err> os: xpsr: 0x21000000
[00:00:25.283,142] <err> os: s[ 0]: 0x200040e4 s[ 1]: 0x2000230c s[ 2]: 0x00000000 s[ 3]: 0x2000237c
[00:00:25.283,782] <err> os: s[ 4]: 0x20004107 s[ 5]: 0x200040fe s[ 6]: 0x00000000 s[ 7]: 0x000035ab
[00:00:25.284,393] <err> os: s[ 8]: 0x20004106 s[ 9]: 0x00000004 s[10]: 0x2000be89 s[11]: 0x2000230c
[00:00:25.285,034] <err> os: s[12]: 0x20007744 s[13]: 0x00000000 s[14]: 0x00054519 s[15]: 0x00000000
[00:00:25.285,614] <err> os: fpscr: 0x00000000
[00:00:25.285,949] <err> os: Faulting instruction address (r15/pc): 0x00011540
[00:00:25.286,376] <err> os: >>> ZEPHYR FATAL ERROR 26: Unknown error on CPU 0
[00:00:25.286,804] <err> os: Current thread: 0x200049c0 (MPSL Work)
[00:00:25.297,119] <err> os: Halting system
Here are the logs from the nRF Connect Desktop BLE app:
15:01:54.723 Scan started 15:02:02.547 Connecting to device 15:02:02.578 Connected to device F7:5A:42:28:61:C8: interval: 12.5ms, timeout: 4000ms, latency: 0 15:02:02.626 Data length updated for device F7:5A:42:28:61:C8, new value is 69 15:02:07.035 Disconnected from device F7:5A:42:28:61:C8, reason: BLE_HCI_CONNECTION_TIMEOUT
Is this a known issue? We are hoping you could shed some light on what could be going wrong.
Any help is appreciated.
