I’m using nrfjprog version 10.12.1 and JLinkARM.dll version 6.88.
I encountered an intermittent nrfjprog error when programming firmware to the nRF52833.
In most cases, I can successfully reset the device and update the firmware. However, after approximately 40–50 iterations, an error occurs.
I’ve tried rebooting the system, switching USB ports, and running nrfjprog --recover, but the issue persists.
Here is the error message:
ERROR: JLinkARM DLL reported an error. Try again. If error condition
ERROR: persists, run the same command again with argument --log, contact Nordic
ERROR: Semiconductor and provide the generated log.log file to them.
Below is the log from one of the failed reset attempts.
Since the issue appears to be related to JLinkARM.dll, I would like to ask:
1. Can you help identify the root cause based on the log?
Since the version of JLinkARM.dll I was using was relatively old (v6.88), I updated it to v8.30.
After testing with 60 devices, I haven’t encountered the error so far.
2. If there’s still a chance it may occur again?
[2025-May-06 17:38:46] [ info] nrfjprog --log --reset
[2025-May-06 17:38:46] [ info] nrfjprog version 10.12.1
[2025-May-06 17:38:46] [ info] --------------------------------------------------------------------------------
[2025-May-06 17:38:46] [debug] [ nRF0x0] - open_dll
[2025-May-06 17:38:46] [ info] [ nRF0x0] - Load library at /opt/nrfjprog/libjlinkarm_unknown_nrfjprogdll.so.
[2025-May-06 17:38:46] [ info] [ nRF0x0] - Library loaded, loading member functions.
[2025-May-06 17:38:46] [ info] [ nRF0x0] - Member functions succesfully loaded.
[2025-May-06 17:38:46] [ info] [Backend] - Logger callback at 0x5c27f402e130 registered in Segger backend logger.
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Logger callback at 0x5c27f402e130 registered in JLink logger.
[2025-May-06 17:38:46] [debug] [nRFUnknown] - Just_open_dll_tagged_callback
[2025-May-06 17:38:46] [debug] [Backend] - open_dll
[2025-May-06 17:38:46] [ info] [Backend] - No J-Link DLL path was provided. Attempting to auto detect.
[2025-May-06 17:38:46] [ info] [Backend] - Load library at /opt/SEGGER/JLink/libjlinkarm.so.6.88.1.
[2025-May-06 17:38:46] [ info] [Backend] - Library loaded, loading member functions.
[2025-May-06 17:38:46] [ info] [Backend] - Member functions succesfully loaded.
[2025-May-06 17:38:46] [debug] [Backend] - dll_version
[2025-May-06 17:38:46] [ info] [Backend] - Segger dll version 6.88.a loaded.
[2025-May-06 17:38:46] [debug] [Backend] - set_core_data
[2025-May-06 17:38:46] [debug] [ nRF0x0] - enum_emu_snr
[2025-May-06 17:38:46] [debug] [nRFUnknown] - Just_enum_emu_snr
[2025-May-06 17:38:46] [debug] [Backend] - enum_emu_snr
[2025-May-06 17:38:46] [debug] [Backend] - ---just_enum_emu_snr
[2025-May-06 17:38:46] [debug] [Backend] - ---just_get_num_emus
[2025-May-06 17:38:46] [debug] [ nRF0x0] - connect_to_emu_with_snr
[2025-May-06 17:38:46] [debug] [nRFUnknown] - Just_connect_to_emu_with_snr
[2025-May-06 17:38:46] [debug] [Backend] - connect_to_emu_with_snr
[2025-May-06 17:38:46] [debug] [Backend] - is_connected_to_emu
[2025-May-06 17:38:46] [debug] [Backend] - ---just_enum_emu_snr
[2025-May-06 17:38:46] [debug] [Backend] - ---just_get_num_emus
[2025-May-06 17:38:46] [debug] [Backend] - ---just_connect_to_emu_with_snr
[2025-May-06 17:38:46] [debug] [Backend] - ---just_connect_to_emu_without_snr
[2025-May-06 17:38:46] [ info] [Backend] - Segger logging enabled.
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Firmware: J-Link V11 compiled May 18 2022 17:08:14
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Decompressing FW timestamp took 120 us
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Hardware: V11.00
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] S/N: 51018885
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] OEM: SEGGER
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Feature(s): GDB
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] TELNET listener socket opened on port 19021
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] WEBSRV Starting webserver
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] WEBSRV Webserver running on local port 19080
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 6.326ms returns "O.K."
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_GetHWStatus(...)
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.152ms returns 0
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_ExecCommand("SetRestartOnClose = 0", ...).
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.002ms returns 0x01
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_ExecCommand("DisableFlashDL", ...).
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.002ms returns 0x00
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_ExecCommand("ExcludeFlashCacheRange 0x0-0xFFFFFFFF", ...).
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.001ms returns 0x00
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_SetHookUnsecureDialog
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_SetHookUnsecureDialog(...)
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.005ms returns 0
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_TIF_Select(JLINKARM_TIF_SWD)
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.823ms returns 0x00
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_SetSpeed(2000)
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.194ms
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_GetSN()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.002ms returns 51018885
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [debug] [Backend] - ---just_load_core_data
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_ExecCommand("CORESIGHT_SetIndexAHBAPToUse = 0", ...).
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.001ms returns 0x00
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_ExecCommand("device = Cortex-M4", ...).
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] XML file found at: /opt/SEGGER/JLink/JLinkDevices.xml
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] /opt/SEGGER/JLink/JLinkDevices.xml evaluated successfully.
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Device "CORTEX-M4" selected.
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] Device "CORTEX-M4" selected.
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 7.223ms returns 0x00
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [debug] [ nRF0x0] - read_connected_emu_snr
[2025-May-06 17:38:46] [debug] [nRFUnknown] - Just_read_connected_emu_snr
[2025-May-06 17:38:46] [debug] [Backend] - read_connected_emu_snr
[2025-May-06 17:38:46] [debug] [Backend] - is_connected_to_emu
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_IsOpen()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.003ms returns 0x01
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [debug] [ nRF0x0] - read_device_family
[2025-May-06 17:38:46] [debug] [nRFUnknown] - Just_read_device_family
[2025-May-06 17:38:46] [debug] [Backend] - is_connected_to_emu
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_IsOpen()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] - 0.003ms returns 0x01
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_Lock()
[2025-May-06 17:38:46] [debug] [Backend] - read_debug_port_idr
[2025-May-06 17:38:46] [debug] [Backend] - read_debug_port_register
[2025-May-06 17:38:46] [debug] [Backend] - ---just_read_debug_port_register
[2025-May-06 17:38:46] [debug] [Backend] - coresight_configure
[2025-May-06 17:38:46] [ info] [ JLink] - [Info ] [JLink ] JLINK_CORESIGHT_Configure()
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 100.758ms returns 0
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [debug] [Backend] - ---just_select_debug_port_register
[2025-May-06 17:38:47] [debug] [Backend] - Select AP 255, DP Bank 0, AP Bank 255
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_CORESIGHT_WriteAPDPReg(DP reg 0x02, 0x00000000)
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.845ms returns -1
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [ info] [Backend] - JLinkARM.dll reported "-1", an unknown error.
[2025-May-06 17:38:47] [debug] [Backend] - ---just_abort_debug_action
[2025-May-06 17:38:47] [ info] [Backend] - Attempting to clear any configuration errors in debug port before closing connection.
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_CORESIGHT_WriteAPDPReg(DP reg 0x00, 0x0000001F)
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.734ms returns -1
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [ info] [Backend] - JLinkARM.dll reported "-1", an unknown error.
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.083ms
[2025-May-06 17:38:47] [debug] [ nRF0x0] - close_dll
[2025-May-06 17:38:47] [debug] [nRFUnknown] - Just_close_dll
[2025-May-06 17:38:47] [debug] [Backend] - close
[2025-May-06 17:38:47] [debug] [Backend] - disconnect_from_emu
[2025-May-06 17:38:47] [debug] [Backend] - is_connected_to_emu
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_IsOpen()
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.013ms returns 0x01
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [debug] [Backend] - ---just_disconnect_from_emu
[2025-May-06 17:38:47] [debug] [Backend] - is_connected_to_device
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_IsConnected()
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.012ms returns FALSE
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [debug] [Backend] - ---just_is_debug_region_powered
[2025-May-06 17:38:47] [debug] [Backend] - ---just_read_debug_port_register
[2025-May-06 17:38:47] [debug] [Backend] - is_connected_to_emu
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_IsOpen()
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.017ms returns 0x01
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_Lock()
[2025-May-06 17:38:47] [debug] [Backend] - ---just_select_debug_port_register
[2025-May-06 17:38:47] [debug] [Backend] - Select AP 255, DP Bank 0, AP Bank 255
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_CORESIGHT_WriteAPDPReg(DP reg 0x02, 0x00000000)
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.772ms returns -1
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [ info] [Backend] - JLinkARM.dll reported "-1", an unknown error.
[2025-May-06 17:38:47] [debug] [Backend] - ---just_abort_debug_action
[2025-May-06 17:38:47] [ info] [Backend] - Attempting to clear any configuration errors in debug port before closing connection.
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_CORESIGHT_WriteAPDPReg(DP reg 0x00, 0x0000001F)
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.679ms returns -1
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_HasError()
[2025-May-06 17:38:47] [ info] [Backend] - JLinkARM.dll reported "-1", an unknown error.
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] - 0.036ms
[2025-May-06 17:38:47] [ info] [ JLink] - [Info ] [JLink ] JLINK_Close()
[2025-May-06 17:38:47] [debug] [Backend] - Segger Backend closed.
