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  • Fully compatible with and same features as J-Link OB
  • Wide range of IDEs are supported
  • Virtual COM port (VCOM) support

Converting ST-LINK On-Board Into a J-Link

SEGGER offers a firmware upgrading the ST-LINK on-board on the Nucleo and Discovery Boards.

This firmware makes the ST-LINK on-board compatible with J-Link OB, allowing users to take advantage of most J-Link features like the ultra fast flash download and debugging speed or the free-to-use GDBServer.

Getting Started with ST-LINK On-Board

In order to get started with ST-LINK on-board and upgrade it to a J-Link OB, just a few steps are necessary:

  • Make sure that the ST-LINK USB drivers are installed: Download
  • Make sure that the J-Link software package V5.12b or later is installed: Download
  • Download the SEGGER STLinkReflash utility: Download
  • Start the STLinkReflash utility
  • Agree to the license terms
  • Connect ST-LINK on-board to PC
  • Select "Upgrade to J-Link"
  • Wait for operation to complete
  • Quit the STLinkReflash utility

Terms of use

SEGGER created a firmware which runs on the ST-LINK on-board, making it J-Link compatible. In order to make use of this firmware, the following Terms Of Use must be accepted:

  • The firmware is only to be used with ST target devices. Using it with other devices is prohibited and illegal.
  • The firmware is for use with evaluation boards only. It is not for use with custom hardware.
  • The firmware may only be used for development and/or evaluation purposes. It may not be used for production purposes.
  • The firmware is made available without any warranty and without support.

If there is any doubt if a certain use may be considered within the foregoing scope it is strongly recommended to consult SEGGER prior to use.

When starting a debug session, the following license dialog shows up which must be accepted in order to be able to work with ST-LINK on-board:

Compatible Evaluation Boards

The following evaluation boards have been tested with the J-Link OB firmware and are known to be working. Other evaluation boards may work as well but are not guaranteed to do so. In case of doubt, please consult SEGGER.

  • 32F0308DISCOVERY (STM32F0308-DISCO)
  • 32F3348DISCOVERY (STM32F3348-DISCO)
  • 32F411EDISCOVERY (STM32F411E-DISCO)
  • 32F413HDISCOVERY (STM32F413H-DISCO)
  • 32F429IDISCOVERY (STM32F429I-DISC1)
  • 32F429IDISCOVERY (STM32F429I-DISCO)
  • 32F469IDISCOVERY (STM32F469I-DISCO)
  • 32F723EDISCOVERY (STM32F723E-DISCO)
  • 32F746GDISCOVERY (STM32F746G-DISCO)
  • 32L0538DISCOVERY (STM32L0538-DISCO)
  • 32L100CDISCOVERY (STM32L100C-DISCO)
  • 32L476GDISCOVERY (STM32L476-DISCO)
  • B-L072Z-LRWAN1
  • NUCLEO-F030R8
  • NUCLEO-F031K6
  • NUCLEO-F042K6
  • NUCLEO-F070RB
  • NUCLEO-F072RB
  • NUCLEO-F091RC
  • NUCLEO-F103RB
  • NUCLEO-F207ZG
  • NUCLEO-F302R8
  • NUCLEO-F303K8
  • NUCLEO-F303RE
  • NUCLEO-F303ZE
  • NUCLEO-F334R8
  • NUCLEO-F401RE
  • NUCLEO-F410RB
  • NUCLEO-F411RE
  • NUCLEO-F412ZG
  • NUCLEO-F413ZH
  • NUCLEO-F429ZI
  • NUCLEO-F446RE
  • NUCLEO-F446ZE
  • NUCLEO-F722ZE
  • NUCLEO-F746ZG
  • NUCLEO-F767ZI (Nucleo-144)
  • NUCLEO-L011K4
  • NUCLEO-L031K6
  • NUCLEO-L053R8
  • NUCLEO-L073RZ
  • NUCLEO-L152RE
  • NUCLEO-L452RE
  • NUCLEO-L496ZG
  • NUCLEO-L496ZG-P
  • STM32F0DISCOVERY
  • STM32F3DISCOVERY
  • STM32F4DISCOVERY (STM32F407G-DISC1)

Restore ST-Link Firmware

If, for whatever reason, the original ST-LINK firmware shall be restored and the ST-LINK on-board is already running the J-Link firmware, this can be achieved via the STLinkReflash utility:

  • Start the STLinkReflash utility
  • Agree to the license terms
jlink-stlink-stlinkreflash-1-licsegger.png
License Terms by SEGGER
jlink-stlink-stlinkreflash-2-licst.png
Amendment by ST Microelectronics
  • Connect ST-LINK on-board to PC
  • Select "Restore ST-Link"
  • Wait for operation to complete
  • Quit the STLinkReflash utility

Firmware Version History and Limitations

Firmware Version History

17-06-28:

  • Under special circumstances, heap was overwritten when using HSS functionality. Fixed.

16-08-04:

  • Improved download speed
  • When using RTT and invalid contents were read from RAM, firmware could hang

16-04-15:

  • Initial version that supports ST-LINK/V2 and ST-LINK/V2-1

16-05-04:

  • Added support for SWO

Limitations

The firmware making the ST-LINK on-board J-Link compatible has some limitations in contrast to an original, industry leading SEGGER J-Link:

  • May be used with ARM based ST devices only
  • Only debugging on evaluation boards is allowed. Debugging on custom hardware is not supported and not allowed
  • No production flash programming support
  • Unlimited breakpoints in flash available for evaluation only
  • No support is given

By using an original SEGGER J-Link PROJ-Link ULTRA+ or J-Link PLUS, all these limitations will be gone. Learn more about J-Link.