OTA zip upload issue.

[Embel_Tech]

Hello Nordic Team,

I am implementing OTA in a pairing and bonding-enabled application, but I am facing an issue during the ZIP file upload. Additionally, the graph is not displaying.

I will share my prj.conf and nRF Connect logs as well.

PRJ

PRJ FILE 

########################
# CORE SYSTEM
########################

CONFIG_REBOOT=y

#CONFIG_PWM=y

CONFIG_POWEROFF=y
CONFIG_PM_DEVICE=y
CONFIG_NRFX_POWER=y
# Remove CONFIG_PM=y — it is NOT needed and may silently fail on nRF52833

# Main and workqueue stacks
CONFIG_MAIN_STACK_SIZE=2048
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=4096

# Heap
CONFIG_HEAP_MEM_POOL_SIZE=4096

# Extra stacks – tune down later with thread analyzer if needed
CONFIG_MPSL_WORK_STACK_SIZE=2048
CONFIG_BT_RX_STACK_SIZE=2048
CONFIG_IDLE_STACK_SIZE=1024
CONFIG_ISR_STACK_SIZE=2048



########################
# BLUETOOTH – ROLES
########################

CONFIG_BT=y
CONFIG_BT_CENTRAL=y
CONFIG_BT_PERIPHERAL=y



CONFIG_BT_SMP_APP_PAIRING_ACCEPT=y
CONFIG_BT_FIXED_PASSKEY=y 

# Device name
CONFIG_BT_DEVICE_NAME="CODE_rrr"
#CONFIG_BT_DEVICE_NAME="HANDHELD_SAGAR"

########################
# BLUETOOTH – BUFFERS
########################

# ACL data buffers
CONFIG_BT_BUF_ACL_TX_COUNT=10
CONFIG_BT_BUF_ACL_RX_COUNT=10
CONFIG_BT_BUF_ACL_TX_SIZE=251
CONFIG_BT_BUF_ACL_RX_SIZE=251

# L2CAP
CONFIG_BT_L2CAP_TX_MTU=247
#CONFIG_BT_L2CAP_TX_BUF_COUNT=5
#CONFIG_BT_L2CAP_DYNAMIC_CHANNEL=y

# Controller
CONFIG_BT_CTLR_DATA_LENGTH_MAX=251

########################
# GATT & CLIENTS
########################

CONFIG_BT_GATT_CLIENT=y
CONFIG_BT_GATT_DM=y
#CONFIG_BT_GATT_DM_DATA_PRINT=y

# Nordic UART Service client
#CONFIG_BT_NUS_CLIENT=y


########################
# SCANNING & CONNECTION MGMT
########################

CONFIG_BT_SCAN=y
CONFIG_BT_SCAN_FILTER_ENABLE=y
CONFIG_BT_SCAN_UUID_CNT=1
CONFIG_BT_SCAN_NAME_CNT=1
#CONFIG_BT_SCAN_AND_INITIATE_IN_PARALLEL=y

# Connection parameters (peripheral preference)
CONFIG_BT_GAP_AUTO_UPDATE_CONN_PARAMS=y
CONFIG_BT_PERIPHERAL_PREF_MIN_INT=12
CONFIG_BT_PERIPHERAL_PREF_MAX_INT=12
CONFIG_BT_PERIPHERAL_PREF_TIMEOUT=400

# Request security automatically for GATT
CONFIG_BT_GATT_AUTO_SEC_REQ=y

########################
# FLASH & NVS (FOR SETTINGS/BONDING)
########################

CONFIG_FLASH=y
CONFIG_SOC_FLASH_NRF=y
CONFIG_NRFX_NVMC=y
CONFIG_MPU_ALLOW_FLASH_WRITE=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_FLASH_MAP=y

# NVS and settings backend
CONFIG_NVS=y
CONFIG_SETTINGS=y
CONFIG_SETTINGS_NVS=y

########################
# BLUETOOTH SECURITY / BONDING
########################

CONFIG_BT_BONDABLE=y
CONFIG_BT_SETTINGS=y         # Store bonds in settings (flash) [[Exercise 2](https://academy.nordicsemi.com/courses/bluetooth-low-energy-fundamentals/lessons/lesson-5-bluetooth-le-security-fundamentals/topic/blefund-lesson-5-exercise-2/)]
CONFIG_BT_PRIVACY=n
#CONFIG_BT_RPA_TIMEOUT=900


########################
# GPIO / WDT / CLOCK
########################

CONFIG_GPIO=y

CONFIG_WATCHDOG=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y
CONFIG_CLOCK_CONTROL_NRF_K32SRC_500PPM=y


########################
# LOGGING
########################

CONFIG_LOG=n
CONFIG_LOG_MODE_IMMEDIATE=y

CONFIG_USE_SEGGER_RTT=n
CONFIG_LOG_BACKEND_RTT=n
CONFIG_LOG_BACKEND_UART=n
CONFIG_LOG_PRINTK=n

CONFIG_BT_CONN_CHECK_NULL_BEFORE_CREATE=y

# Limit BT log noise (warning level)
CONFIG_BT_LOG_LEVEL_WRN=n
CONFIG_BT_CONN_LOG_LEVEL_WRN=n
CONFIG_BT_ISO_LOG_LEVEL_WRN=n
CONFIG_BT_HCI_DRIVER_LOG_LEVEL_WRN=n


########################
# DEBUG / OPTIMIZATION
########################
#CONFIG_DEBUG_OPTIMIZATIONS=y
#CONFIG_DEBUG_THREAD_INFO=y
#CONFIG_INIT_STACKS=y


# Bluetooth Security
CONFIG_BT_SMP=y
#CONFIG_BT_SIGNING=y
#CONFIG_BT_SMP_SC_ONLY=y
#CONFIG_BT_SMP_SC_PAIR_ONLY=y

CONFIG_SETTINGS_RUNTIME=y
CONFIG_BT_MAX_PAIRED=7

# Whitelist/Filter Accept List Support
CONFIG_BT_FILTER_ACCEPT_LIST=y

# Bond Management Service
#CONFIG_BT_BMS=y
#CONFIG_DK_LIBRARY=y

# Connection parameters
CONFIG_BT_MAX_CONN=7
CONFIG_BT_L2CAP_TX_BUF_COUNT=7

# Flash partitions (already present but ensure they exist)
CONFIG_PM_PARTITION_SIZE_SETTINGS_STORAGE=0x2000


# I2C Configuration
CONFIG_I2C=y
CONFIG_I2C_NRFX=y

# ADC Driver Configuration
CONFIG_ADC=y
CONFIG_ADC_NRFX_SAADC=y



CONFIG_BT_DATA_LEN_UPDATE=n
CONFIG_BT_PHY_UPDATE=n
CONFIG_BT_GATT_CACHING=y
CONFIG_BT_GATT_SERVICE_CHANGED=y
CONFIG_BT_GAP_PERIPHERAL_PREF_PARAMS=n
#CONFIG_BT_HCI_VS_EXT=n
CONFIG_BT_ASSERT=n          
CONFIG_BT_CTLR_PRIVACY=n
CONFIG_BT_CTLR_PHY_2M=n

CONFIG_SIZE_OPTIMIZATIONS=y
CONFIG_MINIMAL_LIBC=y

CONFIG_LTO=y
CONFIG_ISR_TABLES_LOCAL_DECLARATION=y





# BLE DFU via MCUmgr (recommended helper)
CONFIG_NCS_SAMPLE_MCUMGR_BT_OTA_DFU=y

# Optional: speed up DFU, automatically extends BT buffers & data length
CONFIG_NCS_SAMPLE_MCUMGR_BT_OTA_DFU_SPEEDUP=y

#
# 32 kHz RC oscillator for custom board 
CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y







# Flash support (required for MCUboot / DFU)
CONFIG_FLASH=y

CONFIG_FLASH_PAGE_LAYOUT=y

CONFIG_FLASH_MAP=y




CONFIG_MCUMGR_TRANSPORT_BT=y
CONFIG_MCUMGR_TRANSPORT_BT_REASSEMBLY=y

# 🔐 add here
CONFIG_MCUMGR_TRANSPORT_BT_PERM_RW_AUTHEN=y

NRF LOGS 

nRF Connect, 2026-03-25
CODE_YYY (C3:CC:AC:9C:D2:13)
I 09:58:53.615 [Server] Server started
V 09:58:53.618 Heart Rate (0x180D)
- Heart Rate Measurement [N] (0x2A37)
   Client Characteristic Configuration (0x2902)
- Body Sensor Location [R] (0x2A38)
- Heart Rate Control Point [W] (0x2A39)
Unknown Service (0000aaa0-0000-1000-8000-aabbccddeeff)
- Unknown Characteristic [N R] (0000aaa1-0000-1000-8000-aabbccddeeff)
   Client Characteristic Configuration (0x2902)
   Unknown Descriptor (0000aab0-0000-1000-8000-aabbccddeeff)
   Characteristic User Description (0x2901)
   Characteristic Presentation Format (0x2904)
- Unknown Characteristic [I W WNR] (0000aaa2-0000-1000-8000-aabbccddeeff)
   Client Characteristic Configuration (0x2902)
User Data (0x181C)
- First Name [R W] (0x2A8A)
- Last Name [R W] (0x2A90)
- Gender [R W] (0x2A8C)
V 09:58:53.895 Connecting to C3:CC:AC:9C:D2:13...
D 09:58:53.895 gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, preferred PHY = LE 1M)
D 09:58:54.090 [Server callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I 09:58:54.090 [Server] Device with address C3:CC:AC:9C:D2:13 connected
D 09:58:54.142 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
D 09:58:54.145 [Callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I 09:58:54.145 Connected to C3:CC:AC:9C:D2:13
V 09:58:54.147 Requesting new MTU...
D 09:58:54.147 gatt.requestMtu(517)
I 09:58:54.647 Connection parameters updated (interval: 7.5ms, latency: 0, timeout: 5000ms)
I 09:58:59.875 MTU changed to: 247
D 09:58:59.876 wait(1600ms)
I 09:58:59.930 Connection parameters updated (interval: 30.0ms, latency: 0, timeout: 5000ms)
V 09:59:01.478 Discovering services...
D 09:59:01.478 gatt.discoverServices()
D 09:59:01.488 [Callback] Services discovered with status: 0
I 09:59:01.488 Services discovered
V 09:59:01.498 Generic Attribute (0x1801)
- Service Changed [I] (0x2A05)
   Client Characteristic Configuration (0x2902)
- Client Supported Features [R W] (0x2B29)
- Database Hash [R] (0x2B2A)
Generic Access (0x1800)
- Device Name [R] (0x2A00)
- Appearance [R] (0x2A01)
Unknown Service (0000b000-4375-7274-204d-6667204c4c43)
- Unknown Characteristic [N] (0000b001-1212-efde-1523-785feabcd123)
   Client Characteristic Configuration (0x2902)
- Unknown Characteristic [R] (0000b002-1212-efde-1523-785feabcd123)
- Unknown Characteristic [R W] (0000b003-1212-efde-1523-785feabcd123)
- Unknown Characteristic [W] (0000b004-1212-efde-1523-785feabcd123)
SMP Service (8d53dc1d-1db7-4cd3-868b-8a527460aa84)
- SMP Characteristic [N WNR] (da2e7828-fbce-4e01-ae9e-261174997c48)
   Client Characteristic Configuration (0x2902)
D 09:59:01.498 gatt.setCharacteristicNotification(00002a05-0000-1000-8000-00805f9b34fb, true)
D 09:59:01.503 gatt.setCharacteristicNotification(0000b001-1212-efde-1523-785feabcd123, true)
V 09:59:05.834 Enabling indications for 00002a05-0000-1000-8000-00805f9b34fb
D 09:59:05.835 gatt.setCharacteristicNotification(00002a05-0000-1000-8000-00805f9b34fb, true)
D 09:59:05.839 gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb, value=0x0200)
I 09:59:05.896 Data written to descr. 00002902-0000-1000-8000-00805f9b34fb, value: (0x) 02-00
A 09:59:05.896 "Indications enabled" sent
V 09:59:05.900 Indications enabled for 00002a05-0000-1000-8000-00805f9b34fb
V 09:59:09.943 Enabling notifications for 0000b001-1212-efde-1523-785feabcd123
D 09:59:09.943 gatt.setCharacteristicNotification(0000b001-1212-efde-1523-785feabcd123, true)
D 09:59:09.946 gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb, value=0x0100)
I 09:59:10.006 Data written to descr. 00002902-0000-1000-8000-00805f9b34fb, value: (0x) 01-00
A 09:59:10.006 "Notifications enabled" sent
V 09:59:10.009 Notifications enabled for 0000b001-1212-efde-1523-785feabcd123
I 09:59:10.488 Notification received from 0000b001-1212-efde-1523-785feabcd123, value: (0x) 00-00-01-01
A 09:59:10.488 "(0x) 00-00-01-01" received
V 09:59:12.116 Enabling notifications for da2e7828-fbce-4e01-ae9e-261174997c48
D 09:59:12.116 gatt.setCharacteristicNotification(da2e7828-fbce-4e01-ae9e-261174997c48, true)
D 09:59:12.120 gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb, value=0x0100)
I 09:59:12.196 Data written to descr. 00002902-0000-1000-8000-00805f9b34fb, value: (0x) 01-00
A 09:59:12.196 "Notifications enabled" sent
V 09:59:12.203 Notifications enabled for da2e7828-fbce-4e01-ae9e-261174997c48
V 09:59:17.084 [McuMgr] Connecting...
D 09:59:17.088 [McuMgr] gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, LE 1M)
D 09:59:17.138 [McuMgr] [Callback] Connection state changed with status: 0 and new state: 2 (CONNECTED)
I 09:59:17.140 [McuMgr] Connected to C3:CC:AC:9C:D2:13
D 09:59:17.142 [McuMgr] wait(1600)
I 09:59:17.143 [McuMgr] MTU changed to: 247
V 09:59:18.747 [McuMgr] Discovering services...
D 09:59:18.754 [McuMgr] gatt.discoverServices()
I 09:59:18.792 [McuMgr] Services discovered
V 09:59:18.794 [McuMgr] Primary service found
V 09:59:18.803 [McuMgr] Requesting new MTU...
D 09:59:18.805 [McuMgr] gatt.requestMtu(498)
I 09:59:18.833 [McuMgr] MTU changed to: 247
D 09:59:18.835 [McuMgr] gatt.setCharacteristicNotification(da2e7828-fbce-4e01-ae9e-261174997c48, true)
V 09:59:18.838 [McuMgr] Enabling notifications for da2e7828-fbce-4e01-ae9e-261174997c48
D 09:59:18.848 [McuMgr] gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb, value=0x01-00)
I 09:59:18.915 [McuMgr] Data written to descr. 00002902-0000-1000-8000-00805f9b34fb
V 09:59:18.919 [McuMgr] Waiting for value change...
V 09:59:18.922 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 09:59:18.925 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48, value=0x000000010000FF06A0, WRITE COMMAND)
I 09:59:18.935 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 09:59:18.982 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 01-00-00-19-00-00-FF-06-BF-68-62-75-66-5F-73-69-7A-65-19-09-AB-69-62-75-66-5F-63-6F-75-6E-74-04-FF
I 09:59:18.984 [McuMgr] Wait for value changed complete
A 09:59:18.988 [McuMgr] Received Header (Version: 0, Op: 1, Flags: 0, Len: 25, Group: 0, Seq: 255, Command: 6) CBOR {"buf_size":2475,"buf_count":4}
I 09:59:18.998 [McuMgr] SMP reassembly supported with buffer size: 2475 bytes and count: 4
V 09:59:19.000 [McuMgr] Requesting connection priority: HIGH (11.25–15ms, 0, 5s)...
D 09:59:19.001 [McuMgr] gatt.requestConnectionPriority(HIGH)
A 09:59:19.010 [McuMgr] Sending (9 bytes) Header (Version: 1, Op: 0, Flags: 0, Len: 1, Group: 0, Seq: 0, Command: 8) CBOR {}
V 09:59:19.206 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 09:59:19.210 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48, value=0x0800000100000008A0, WRITE COMMAND)
I 09:59:19.237 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 09:59:19.275 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 09-00-00-15-00-00-00-08-BF-6A-62-6F-6F-74-6C-6F-61-64-65-72-67-4D-43-55-62-6F-6F-74-FF
A 09:59:19.278 [McuMgr] Received Header (Version: 1, Op: 1, Flags: 0, Len: 21, Group: 0, Seq: 0, Command: 8) CBOR {"bootloader":"MCUboot"}
A 09:59:19.296 [McuMgr] Sending (20 bytes) Header (Version: 1, Op: 0, Flags: 0, Len: 12, Group: 0, Seq: 1, Command: 8) CBOR {"query":"mode"}
V 09:59:19.299 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 09:59:19.300 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48, value=0x0800000C00000108A1657175657279646D6F6465, WRITE COMMAND)
I 09:59:19.313 Connection parameters updated (interval: 15.0ms, latency: 0, timeout: 5000ms)
I 09:59:19.335 [McuMgr] Connection parameters updated (interval: 15.0ms, latency: 0, timeout: 5000ms)
I 09:59:19.337 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 09:59:19.341 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 09-00-00-08-00-00-01-08-BF-64-6D-6F-64-65-03-FF
A 09:59:19.344 [McuMgr] Received Header (Version: 1, Op: 1, Flags: 0, Len: 8, Group: 0, Seq: 1, Command: 8) CBOR {"mode":3}
A 09:59:19.363 [McuMgr] Sending (9 bytes) Header (Version: 1, Op: 0, Flags: 0, Len: 1, Group: 1, Seq: 2, Command: 0) CBOR {}
V 09:59:19.365 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 09:59:19.366 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48, value=0x0800000100010200A0, WRITE COMMAND)
I 09:59:19.373 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 09:59:19.401 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 09-00-00-F6-00-01-02-00-BF-66-69-6D-61-67-65-73-9F-BF-64-73-6C-6F-74-00-67-76-65-72-73-69-6F-6E-67-31-2E-30-2E-31-2E-36-64-68-61-73-68-58-20-15-C2-FF-B0-05-A8-89-D1-90-D9-E7-2D-4C-37-17-8C-D4-C5-79-97-CD-19-3C-72-50-88-51-09-A5-85-D8-9C-68-62-6F-6F-74-61-62-6C-65-F5-67-70-65-6E-64-69-6E-67-F4-69-63-6F-6E-66-69-72-6D-65-64-F5-66-61-63-74-69-76-65-F5-69-70-65-72-6D-61-6E-65-6E-74-F4-FF-BF-64-73-6C-6F-74-01-67-76-65-72-73-69-6F-6E-65-30-2E-30-2E-30-64-68-61-73-68-58-20-DB-48-AC-C9-FA-4E-54-BA-30-83-8C-C8-F1-A7-2C-FD-72-14-63-6B-DC-B5-DD-B9-17-E4-FB-B4-8C-63-E5-6B-68-62-6F-6F-74-61-62-6C-65-F5-67-70-65-6E-64-69-6E-67-F5-69-63-6F-6E-66-69-72-6D-65-64-F4-66-61-63-74-69-76-65-F4-69-70-65-72-6D-61-6E-65-6E-74-F4-FF-FF-6B-73-70-6C
I 09:59:19.404 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 69-74-53-74-61-74-75-73-00-FF
A 09:59:19.407 [McuMgr] Received Header (Version: 1, Op: 1, Flags: 0, Len: 246, Group: 1, Seq: 2, Command: 0) CBOR {"images":[{"slot":0,"version":"1.0.1.6","hash":"FcL/sAWoidGQ2ectTDcXjNTFeZfNGTxyUIhRCaWF2Jw=","bootable":true,"pending":false,"confirmed":true,"active":true,"permanent":false},{"slot":1,"version":"0.0.0","hash":"20isyfpOVLowg4zI8acs/XIUY2vctd25F+T7tIxj5Ws=","bootable":true,"pending":true,"confirmed":false,"active":false,"permanent":false}],"splitStatus":0}
V 09:59:19.416 [McuMgr] New state: RESET
A 09:59:19.431 [McuMgr] Sending (9 bytes) Header (Version: 1, Op: 2, Flags: 0, Len: 1, Group: 0, Seq: 3, Command: 5) CBOR {}
V 09:59:19.433 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 09:59:19.435 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48, value=0x0A00000100000305A0, WRITE COMMAND)
I 09:59:19.463 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 09:59:19.479 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 0B-00-00-02-00-00-03-05-BF-FF
A 09:59:19.482 [McuMgr] Received Header (Version: 1, Op: 3, Flags: 0, Len: 2, Group: 0, Seq: 3, Command: 5) CBOR {}
D 09:59:24.747 [Server callback] Connection state changed with status: 0 and new state: DISCONNECTED (0)
I 09:59:24.747 [Server] Device disconnected
D 09:59:24.769 [Callback] Connection state changed with status: 8 and new state: DISCONNECTED (0)
E 09:59:24.769 Error 8 (0x8): GATT CONN TIMEOUT
I 09:59:24.769 Disconnected
D 09:59:24.803 [McuMgr] [Callback] Connection state changed with status: 8 and new state: 0 (DISCONNECTED)
W 09:59:24.806 [McuMgr] Error: (0x8): GATT CONN TIMEOUT
I 09:59:24.811 [McuMgr] Disconnected
D 09:59:24.838 [McuMgr] gatt.close()
D 09:59:24.854 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED
V 09:59:29.495 [McuMgr] Uploading firmware...
D 09:59:29.809 [Server callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I 09:59:29.809 [Server] Device with address C3:CC:AC:9C:D2:13 connected
D 09:59:29.860 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED

 

[Menon]

Hello,

Which nRF device are you using here? Are you working with a DK or a custom board? Please share the SDK version as well.

I see that you have enabled logs via RTT. Could you share those as well? They might provide more details about the issue you are seeing. I also recommend enabling the MCUboot logs, as this may provide more details.

Does this happen only with the ZIP file? Have you tried using a .bin file instead? Also, what happens when you try using the Device Manager application?

Kind Regards,

Abhijith

[Embel_Tech]

Hello Abhijith,

I am using an nRF52833 custom board with SDK version 2.9.0. I am encountering an issue where error code -28 appears in the RTT logs.

I have uploaded the ZIP file, but I have not yet tried using the BIN file.

I will share the RTT logs separately for your reference. Could you please review and help identify the cause of this issue?

RF Connect, 2026-03-28
Handheld_Ota (C3:CC:AC:9C:D2:13)
V 11:35:35.364 Connecting to C3:CC:AC:9C:D2:13...
D 11:35:35.364 gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, preferred PHY = LE 1M)
D 11:35:39.596 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
D 11:35:39.596 [Callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I 11:35:39.596 Connected to C3:CC:AC:9C:D2:13
V 11:35:39.621 Discovering services...
D 11:35:39.621 gatt.discoverServices()
D 11:35:39.792 [Broadcast] Action received: android.bluetooth.device.action.BOND_STATE_CHANGED, bond state changed to: BONDING (11)
D 11:35:39.824 [Broadcast] Action received: android.bluetooth.device.extra.PAIRING_VARIANT, pairing variant: CONSENT
I 11:35:40.028 Connection parameters updated (interval: 7.5ms, latency: 0, timeout: 5000ms)
D 11:35:40.329 [Callback] Services discovered with status: 0
I 11:35:40.329 Services discovered
V 11:35:40.349 Generic Attribute (0x1801)
- Service Changed [I] (0x2A05)
   Client Characteristic Configuration (0x2902)
Generic Access (0x1800)
- Device Name [R] (0x2A00)
- Appearance [R] (0x2A01)
Unknown Service (0000b000-4375-7274-204d-6667204c4c43)
- Unknown Characteristic [N] (0000b001-1212-efde-1523-785feabcd123)
   Client Characteristic Configuration (0x2902)
- Unknown Characteristic [R] (0000b002-1212-efde-1523-785feabcd123)
- Unknown Characteristic [R W] (0000b003-1212-efde-1523-785feabcd123)
   Characteristic User Description (0x2901)
- Unknown Characteristic [W] (0000b004-1212-efde-1523-785feabcd123)
SMP Service (8d53dc1d-1db7-4cd3-868b-8a527460aa84)
- SMP Characteristic [N WNR] (da2e7828-fbce-4e01-ae9e-261174997c48)
   Client Characteristic Configuration (0x2902)
D 11:35:40.349 gatt.setCharacteristicNotification(00002a05-0000-1000-8000-00805f9b34fb, true)
D 11:35:40.351 gatt.setCharacteristicNotification(0000b001-1212-efde-1523-785feabcd123, true)
I 11:35:40.432 Connection parameters updated (interval: 45.0ms, latency: 0, timeout: 5000ms)
D 11:35:44.354 [Broadcast] Action received: android.bluetooth.device.action.BOND_STATE_CHANGED, bond state changed to: NONE (10), reason: REMOVED (9)
I 11:35:44.354 Bonding failed, reason: REMOVED (9)
D 11:35:44.388 [Callback] Connection state changed with status: 5 and new state: DISCONNECTED (0)
E 11:35:44.388 Error 5 (0x5): UNKNOWN (5)
I 11:35:44.388 Disconnected
D 11:35:44.462 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED
D 11:35:46.206 gatt.close()
D 11:35:46.212 wait(200)
V 11:35:46.413 Connecting to C3:CC:AC:9C:D2:13...
D 11:35:46.413 gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, preferred PHY = LE 1M)
D 11:35:47.551 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
D 11:35:47.557 [Callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I 11:35:47.557 Connected to C3:CC:AC:9C:D2:13
V 11:35:47.559 Discovering services...
D 11:35:47.559 gatt.discoverServices()
D 11:35:47.762 [Broadcast] Action received: android.bluetooth.device.action.BOND_STATE_CHANGED, bond state changed to: BONDING (11)
D 11:35:47.807 [Broadcast] Action received: android.bluetooth.device.extra.PAIRING_VARIANT, pairing variant: CONSENT
I 11:35:47.990 Connection parameters updated (interval: 7.5ms, latency: 0, timeout: 5000ms)
D 11:35:48.307 [Callback] Services discovered with status: 0
I 11:35:48.307 Services discovered
V 11:35:48.316 Generic Attribute (0x1801)
- Service Changed [I] (0x2A05)
   Client Characteristic Configuration (0x2902)
Generic Access (0x1800)
- Device Name [R] (0x2A00)
- Appearance [R] (0x2A01)
Unknown Service (0000b000-4375-7274-204d-6667204c4c43)
- Unknown Characteristic [N] (0000b001-1212-efde-1523-785feabcd123)
   Client Characteristic Configuration (0x2902)
- Unknown Characteristic [R] (0000b002-1212-efde-1523-785feabcd123)
- Unknown Characteristic [R W] (0000b003-1212-efde-1523-785feabcd123)
   Characteristic User Description (0x2901)
- Unknown Characteristic [W] (0000b004-1212-efde-1523-785feabcd123)
SMP Service (8d53dc1d-1db7-4cd3-868b-8a527460aa84)
- SMP Characteristic [N WNR] (da2e7828-fbce-4e01-ae9e-261174997c48)
   Client Characteristic Configuration (0x2902)
D 11:35:48.317 gatt.setCharacteristicNotification(00002a05-0000-1000-8000-00805f9b34fb, true)
D 11:35:48.317 gatt.setCharacteristicNotification(0000b001-1212-efde-1523-785feabcd123, true)
I 11:35:48.394 Connection parameters updated (interval: 45.0ms, latency: 0, timeout: 5000ms)
D 11:35:49.509 [Broadcast] Action received: android.bluetooth.device.extra.PAIRING_VARIANT, pairing variant: PIN
D 11:36:00.864 [Broadcast] Action received: android.bluetooth.device.action.BOND_STATE_CHANGED, bond state changed to: BONDED (12)
I 11:36:00.864 Device bonded
V 11:36:01.512 [McuMgr] Connecting...
D 11:36:01.530 [McuMgr] gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, LE 1M)
D 11:36:01.594 [McuMgr] [Callback] Connection state changed with status: 0 and new state: 2 (CONNECTED)
I 11:36:01.607 [McuMgr] Connected to C3:CC:AC:9C:D2:13
D 11:36:01.616 [McuMgr] wait(1600)
V 11:36:03.226 [McuMgr] Discovering services...
D 11:36:03.238 [McuMgr] gatt.discoverServices()
I 11:36:03.268 [McuMgr] Services discovered
V 11:36:03.281 [McuMgr] Primary service found
V 11:36:03.307 [McuMgr] Requesting new MTU...
D 11:36:03.322 [McuMgr] gatt.requestMtu(498)
I 11:36:03.431 [McuMgr] MTU changed to: 247
D 11:36:03.453 [McuMgr] gatt.setCharacteristicNotification(da2e7828-fbce-4e01-ae9e-261174997c48, true)
V 11:36:03.473 [McuMgr] Enabling notifications for da2e7828-fbce-4e01-ae9e-261174997c48
D 11:36:03.484 [McuMgr] descriptor.setValue(0x01-00)
D 11:36:03.496 [McuMgr] gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb)
I 11:36:03.562 [McuMgr] Data written to descr. 00002902-0000-1000-8000-00805f9b34fb
I 11:36:03.572 [McuMgr] Notifications enabled
V 11:36:03.589 [McuMgr] Waiting for value change...
V 11:36:03.600 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:36:03.611 [McuMgr] characteristic.setValue(0x000000010000FF06A0)
D 11:36:03.621 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:36:03.632 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:36:03.647 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:36:03.743 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 01-00-00-19-00-00-FF-06-BF-68-62-75-66-5F-73-69-7A-65-19-09-AB-69-62-75-66-5F-63-6F-75-6E-74-04-FF
I 11:36:03.754 [McuMgr] Wait for value changed complete
A 11:36:03.777 [McuMgr] Received Header (Version: 0, Op: 1, Flags: 0, Len: 25, Group: 0, Seq: 255, Command: 6) CBOR {"buf_size":2475,"buf_count":4}
I 11:36:03.803 [McuMgr] SMP reassembly supported with buffer size: 2475 bytes and count: 4
V 11:36:03.817 [McuMgr] Requesting connection priority: HIGH (11.25–15ms, 0, 5s)...
D 11:36:03.826 [McuMgr] gatt.requestConnectionPriority(HIGH)
A 11:36:03.839 [McuMgr] Sending (9 bytes) Header (Version: 1, Op: 0, Flags: 0, Len: 1, Group: 0, Seq: 0, Command: 8) CBOR {}
V 11:36:04.035 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:36:04.052 [McuMgr] characteristic.setValue(0x0800000100000008A0)
D 11:36:04.064 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:36:04.077 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:36:04.092 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:36:04.146 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 09-00-00-15-00-00-00-08-BF-6A-62-6F-6F-74-6C-6F-61-64-65-72-67-4D-43-55-62-6F-6F-74-FF
A 11:36:04.158 [McuMgr] Received Header (Version: 1, Op: 1, Flags: 0, Len: 21, Group: 0, Seq: 0, Command: 8) CBOR {"bootloader":"MCUboot"}
A 11:36:04.200 [McuMgr] Sending (20 bytes) Header (Version: 1, Op: 0, Flags: 0, Len: 12, Group: 0, Seq: 1, Command: 8) CBOR {"query":"mode"}
V 11:36:04.210 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:36:04.220 [McuMgr] characteristic.setValue(0x0800000C00000108A1657175657279646D6F6465)
D 11:36:04.230 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:36:04.238 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:36:04.249 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:36:04.281 Connection parameters updated (interval: 15.0ms, latency: 0, timeout: 5000ms)
I 11:36:04.290 [McuMgr] Connection parameters updated (interval: 15.0ms, latency: 0, timeout: 5000ms)
I 11:36:04.302 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 09-00-00-08-00-00-01-08-BF-64-6D-6F-64-65-03-FF
A 11:36:04.314 [McuMgr] Received Header (Version: 1, Op: 1, Flags: 0, Len: 8, Group: 0, Seq: 1, Command: 8) CBOR {"mode":3}
A 11:36:04.333 [McuMgr] Sending (9 bytes) Header (Version: 1, Op: 0, Flags: 0, Len: 1, Group: 1, Seq: 2, Command: 0) CBOR {}
V 11:36:04.341 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:36:04.348 [McuMgr] characteristic.setValue(0x0800000100010200A0)
D 11:36:04.354 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:36:04.364 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:36:04.385 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:36:04.415 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 09-00-00-88-00-01-02-00-BF-66-69-6D-61-67-65-73-9F-BF-64-73-6C-6F-74-00-67-76-65-72-73-69-6F-6E-67-32-2E-30-2E-35-2E-39-64-68-61-73-68-58-20-A0-44-86-C8-BD-51-83-20-8E-6C-20-B9-A1-69-40-84-9C-65-5D-A8-B1-07-FF-42-E2-1E-02-81-09-98-27-5F-68-62-6F-6F-74-61-62-6C-65-F5-67-70-65-6E-64-69-6E-67-F4-69-63-6F-6E-66-69-72-6D-65-64-F5-66-61-63-74-69-76-65-F5-69-70-65-72-6D-61-6E-65-6E-74-F4-FF-FF-6B-73-70-6C-69-74-53-74-61-74-75-73-00-FF
A 11:36:04.424 [McuMgr] Received Header (Version: 1, Op: 1, Flags: 0, Len: 136, Group: 1, Seq: 2, Command: 0) CBOR {"images":[{"slot":0,"version":"2.0.5.9","hash":"oESGyL1RgyCObCC5oWlAhJxlXaixB/9C4h4CgQmYJ18=","bootable":true,"pending":false,"confirmed":true,"active":true,"permanent":false}],"splitStatus":0}
V 11:36:04.462 [McuMgr] Uploading firmware...
D 11:36:09.569 [Callback] Connection state changed with status: 8 and new state: DISCONNECTED (0)
E 11:36:09.569 Error 8 (0x8): GATT CONN TIMEOUT
I 11:36:09.569 Disconnected
W 11:36:09.596 [McuMgr] Error: (0x8): GATT CONN TIMEOUT
D 11:36:09.621 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED
W 11:36:14.665 [McuMgr] Error: (0x85): GATT ERROR
W 11:36:20.421 [McuMgr] Error: (0x85): GATT ERROR
W 11:36:26.174 [McuMgr] Error: (0x85): GATT ERROR
D 11:36:27.690 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
W 11:36:35.472 [McuMgr] Error: (0x8): GATT CONN TIMEOUT
D 11:36:35.520 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED
W 11:36:40.565 [McuMgr] Error: (0x85): GATT ERROR
W 11:36:46.320 [McuMgr] Error: (0x85): GATT ERROR
W 11:36:52.073 [McuMgr] Error: (0x85): GATT ERROR
D 11:36:53.575 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
W 11:37:01.351 [McuMgr] Error: (0x8): GATT CONN TIMEOUT
D 11:37:01.386 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED
W 11:37:06.433 [McuMgr] Error: (0x85): GATT ERROR
W 11:37:12.202 [McuMgr] Error: (0x85): GATT ERROR
W 11:37:17.950 [McuMgr] Error: (0x85): GATT ERROR
D 11:37:19.446 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
A 11:37:34.330 [McuMgr] 174355 bytes sent in 64216 ms (2.72 kB/s)
V 11:37:34.347 [McuMgr] New state: TEST
A 11:37:34.392 [McuMgr] Sending (57 bytes) Header (Version: 1, Op: 2, Flags: 0, Len: 49, Group: 1, Seq: 67, Command: 0) CBOR {"confirm":false,"hash":"JML6yWUZSUcruxziBcZ06giagdLA+JjMv3BBZLIDLR0="}
V 11:37:34.402 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:37:34.410 [McuMgr] characteristic.setValue(0x0A00003100014300A267636F6E6669726DF46468617368582024C2FAC9651949472BBB1CE205C674EA089A81D2C0F898CCBF704164B2032D1D)
D 11:37:34.418 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:37:34.426 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:37:34.435 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:37:34.513 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 0B-00-00-F8-00-01-43-00-BF-66-69-6D-61-67-65-73-9F-BF-64-73-6C-6F-74-00-67-76-65-72-73-69-6F-6E-67-32-2E-30-2E-35-2E-39-64-68-61-73-68-58-20-A0-44-86-C8-BD-51-83-20-8E-6C-20-B9-A1-69-40-84-9C-65-5D-A8-B1-07-FF-42-E2-1E-02-81-09-98-27-5F-68-62-6F-6F-74-61-62-6C-65-F5-67-70-65-6E-64-69-6E-67-F4-69-63-6F-6E-66-69-72-6D-65-64-F5-66-61-63-74-69-76-65-F5-69-70-65-72-6D-61-6E-65-6E-74-F4-FF-BF-64-73-6C-6F-74-01-67-76-65-72-73-69-6F-6E-67-31-2E-30-2E-30-2E-35-64-68-61-73-68-58-20-24-C2-FA-C9-65-19-49-47-2B-BB-1C-E2-05-C6-74-EA-08-9A-81-D2-C0-F8-98-CC-BF-70-41-64-B2-03-2D-1D-68-62-6F-6F-74-61-62-6C-65-F5-67-70-65-6E-64-69-6E-67-F5-69-63-6F-6E-66-69-72-6D-65-64-F4-66-61-63-74-69-76-65-F4-69-70-65-72-6D-61-6E-65-6E-74-F4-FF-FF-6B-73
I 11:37:34.527 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 70-6C-69-74-53-74-61-74-75-73-00-FF
A 11:37:34.537 [McuMgr] Received Header (Version: 1, Op: 3, Flags: 0, Len: 248, Group: 1, Seq: 67, Command: 0) CBOR {"images":[{"slot":0,"version":"2.0.5.9","hash":"oESGyL1RgyCObCC5oWlAhJxlXaixB/9C4h4CgQmYJ18=","bootable":true,"pending":false,"confirmed":true,"active":true,"permanent":false},{"slot":1,"version":"1.0.0.5","hash":"JML6yWUZSUcruxziBcZ06giagdLA+JjMv3BBZLIDLR0=","bootable":true,"pending":true,"confirmed":false,"active":false,"permanent":false}],"splitStatus":0}
V 11:37:34.572 [McuMgr] New state: RESET
A 11:37:34.591 [McuMgr] Sending (9 bytes) Header (Version: 1, Op: 2, Flags: 0, Len: 1, Group: 0, Seq: 68, Command: 5) CBOR {}
V 11:37:34.599 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:37:34.608 [McuMgr] characteristic.setValue(0x0A00000100004405A0)
D 11:37:34.627 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:37:34.634 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:37:34.657 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:37:34.775 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 0B-00-00-02-00-00-44-05-BF-FF
A 11:37:34.789 [McuMgr] Received Header (Version: 1, Op: 3, Flags: 0, Len: 2, Group: 0, Seq: 68, Command: 5) CBOR {}
D 11:37:39.976 [McuMgr] [Callback] Connection state changed with status: 8 and new state: 0 (DISCONNECTED)
W 11:37:40.012 [McuMgr] Error: (0x8): GATT CONN TIMEOUT
I 11:37:40.025 [McuMgr] Disconnected
D 11:37:40.053 [McuMgr] gatt.close()
D 11:37:40.087 [Broadcast] Action received: android.bluetooth.device.action.ACL_DISCONNECTED
V 11:37:44.821 [McuMgr] Connecting...
D 11:37:44.834 [McuMgr] gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, LE 1M)
V 11:37:44.854 [McuMgr] New state: CONFIRM
D 11:37:45.047 [Broadcast] Action received: android.bluetooth.device.action.ACL_CONNECTED
D 11:37:45.071 [McuMgr] [Callback] Connection state changed with status: 0 and new state: 2 (CONNECTED)
I 11:37:45.093 [McuMgr] Connected to C3:CC:AC:9C:D2:13
D 11:37:45.105 [McuMgr] wait(1600)
V 11:37:46.715 [McuMgr] Discovering services...
D 11:37:46.731 [McuMgr] gatt.discoverServices()
I 11:37:46.747 [McuMgr] Services discovered
V 11:37:46.756 [McuMgr] Primary service found
V 11:37:46.764 [McuMgr] Requesting new MTU...
D 11:37:46.773 [McuMgr] gatt.requestMtu(498)
I 11:37:46.836 [McuMgr] MTU changed to: 247
D 11:37:46.848 [McuMgr] gatt.setCharacteristicNotification(da2e7828-fbce-4e01-ae9e-261174997c48, true)
V 11:37:46.860 [McuMgr] Enabling notifications for da2e7828-fbce-4e01-ae9e-261174997c48
D 11:37:46.869 [McuMgr] descriptor.setValue(0x01-00)
D 11:37:46.877 [McuMgr] gatt.writeDescriptor(00002902-0000-1000-8000-00805f9b34fb)
I 11:37:46.971 [McuMgr] Data written to descr. 00002902-0000-1000-8000-00805f9b34fb
I 11:37:46.983 [McuMgr] Notifications enabled
V 11:37:46.995 [McuMgr] Waiting for value change...
V 11:37:47.007 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:37:47.015 [McuMgr] characteristic.setValue(0x000000010000FF06A0)
D 11:37:47.023 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:37:47.030 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:37:47.041 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:37:47.107 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 01-00-00-19-00-00-FF-06-BF-68-62-75-66-5F-73-69-7A-65-19-09-AB-69-62-75-66-5F-63-6F-75-6E-74-04-FF
I 11:37:47.119 [McuMgr] Wait for value changed complete
A 11:37:47.129 [McuMgr] Received Header (Version: 0, Op: 1, Flags: 0, Len: 25, Group: 0, Seq: 255, Command: 6) CBOR {"buf_size":2475,"buf_count":4}
I 11:37:47.145 [McuMgr] SMP reassembly supported with buffer size: 2475 bytes and count: 4
A 11:37:47.157 [McuMgr] Sending (57 bytes) Header (Version: 1, Op: 2, Flags: 0, Len: 49, Group: 1, Seq: 0, Command: 0) CBOR {"confirm":true,"hash":"JML6yWUZSUcruxziBcZ06giagdLA+JjMv3BBZLIDLR0="}
V 11:37:47.167 [McuMgr] Writing characteristic da2e7828-fbce-4e01-ae9e-261174997c48 (WRITE COMMAND)
D 11:37:47.176 [McuMgr] characteristic.setValue(0x0A00003100010000A267636F6E6669726DF56468617368582024C2FAC9651949472BBB1CE205C674EA089A81D2C0F898CCBF704164B2032D1D)
D 11:37:47.186 [McuMgr] characteristic.setWriteType(WRITE COMMAND)
D 11:37:47.194 [McuMgr] gatt.writeCharacteristic(da2e7828-fbce-4e01-ae9e-261174997c48)
I 11:37:47.205 [McuMgr] Data written to da2e7828-fbce-4e01-ae9e-261174997c48
I 11:37:47.288 [McuMgr] Notification received from da2e7828-fbce-4e01-ae9e-261174997c48, value: (0x) 0B-00-00-14-00-01-00-00-BF-63-65-72-72-BF-65-67-72-6F-75-70-01-62-72-63-18-1C-FF-FF
A 11:37:47.303 [McuMgr] Received Header (Version: 1, Op: 3, Flags: 0, Len: 20, Group: 1, Seq: 0, Command: 0) CBOR {"err":{"group":1,"rc":28}}
V 11:37:47.337 [McuMgr] Disconnecting...
D 11:37:47.346 [McuMgr] gatt.disconnect()
D 11:37:47.371 [McuMgr] [Callback] Connection state changed with status: 0 and new state: 0 (DISCONNECTED)
I 11:37:47.379 [McuMgr] Disconnected
D 11:37:47.390 [McuMgr] gatt.close()
D 11:37:47.412 gatt.close()
D 11:37:47.418 wait(200)
V 11:37:47.619 Connecting to C3:CC:AC:9C:D2:13...
D 11:37:47.619 gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, preferred PHY = LE 1M)
D 11:37:47.641 [Callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I 11:37:47.641 Connected to C3:CC:AC:9C:D2:13
D 11:37:47.642 wait(1600ms)
V 11:37:49.243 Discovering services...
D 11:37:49.243 gatt.discoverServices()
D 11:37:49.249 [Callback] Services discovered with status: 0
I 11:37:49.249 Services discovered
V 11:37:49.264 Generic Attribute (0x1801)
- Service Changed [I] (0x2A05)
   Client Characteristic Configuration (0x2902)
Generic Access (0x1800)
- Device Name [R] (0x2A00)
- Appearance [R] (0x2A01)
Unknown Service (0000b000-4375-7274-204d-6667204c4c43)
- Unknown Characteristic [N] (0000b001-1212-efde-1523-785feabcd123)
   Client Characteristic Configuration (0x2902)
- Unknown Characteristic [R] (0000b002-1212-efde-1523-785feabcd123)
- Unknown Characteristic [R W] (0000b003-1212-efde-1523-785feabcd123)
   Characteristic User Description (0x2901)
- Unknown Characteristic [W] (0000b004-1212-efde-1523-785feabcd123)
SMP Service (8d53dc1d-1db7-4cd3-868b-8a527460aa84)
- SMP Characteristic [N WNR] (da2e7828-fbce-4e01-ae9e-261174997c48)
   Client Characteristic Configuration (0x2902)
D 11:37:49.264 gatt.setCharacteristicNotification(00002a05-0000-1000-8000-00805f9b34fb, true)
D 11:37:49.267 gatt.setCharacteristicNotification(0000b001-1212-efde-1523-785feabcd123, true)

[Menon]

Hello,

Apologies for the delayed response. We had the Easter holiday here in Norway, which caused the delay.

The logs from the mobile application do not provide much information and are not sufficient on their own to diagnose the final boot/confirmation failure. The issue could be on the target device, which is why I requested logs from both the application and the bootloader.
I appreciate you sharing those logs, as they help narrow down the issue.

Kind Regards,

Abhijith