Skip navigation


SEGGER offers a firmware running on the Spansion eval boards, which provide a on-board debug solution on Spansion MB9AF312K basis.

  • Supports ARM Cortex-M based Spansion boards which come with a on-board debug solution
  • Implements JTAG and SWD debug protocol and virtual COM port functionality



This firmware makes the debug solution on these boards behaving compatible to J-Link LITE, 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, by using a low-cost Spansion eval board platform.

Getting Started

In order to get started with the Spansion on-board debug solution just a few steps are necessary. Note that these steps are only necessary to performed once to initially get the J-Link firmware into the Spansion on-board debug solution. Further firmware updates are performed as with any other J-Link, via the J-Link DLL.

  • Download and install the Spansion USBDirect flash programming utility
  • Make sure that the Spansion eval board is configured to be powered via the USB connector of the on-board debug solution. Configuration may differ for various eval boards. In case a board is not listed here, please refer to the appropriate "firmware update" guide from Spansion, for this board. 
    SK-FMx-xxxPMC-TFT: No special setup required 
    SK-FM4-U120-9B560: Close J15 to enable power via 3.3V. Also close J7 
    SK-FM3-176PMC-ETHERNET V2.0: Close J5 
    SK-FM0-V48-S6E1A1: Close J4 to enable power via 3.3V. Also close J1 
    BULB-BOARD-MINI: No special setup required 
    SK-FM4-216-ETHERNET: Close JP62, JP76, JP77 
    SK-FM4-176L-S6E2CC: Set J4 to 1-2
  • Make sure that the board is configured to boot up in firmware update mode. Configuration may differ for various eval boards. In case a board is not listed here, please refer to the appropriate "firmware update" guide from Spansion, for this board.
    SK-FMx-xxxPMC-TFT: Close JP30 
    SK-FM4-U120-9B560: Close J5 
    SK-FM3-176PMC-ETHERNET V2.0: Close JP47 
    SK-FM0-V48-S6E1A1: Close J8            
    BULB-BOARD-MINI: Close J2 
    SK-FM4-216-ETHERNET: Close JP18
    SK-FM4-176L-S6E2CC: Close JP1
  • Plug-in the eval board via the USB connector that connects the on-board debug solution. It will show up as a virtual COM port at the PC.
  • Start the USBDirect flash programming utility and select MB9AF312K as target device Select the J-Link-OB-MB9AF312K-Spansion_150917.srec as image to be programmed Select the appropriate COM port Hit the "Full operation" button
  • If any jumpers have been set to boot the board in firmware update mode, remove these jumpers
  • Power-cycle the board. It will now boot up as a J-Link.
  • Make sure that the latest J-Link software package is installed: J-Link software package download

Terms of Use


SEGGER created a firmware which runs on the Spansion on-board debug solution, 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 Spansion 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 the J-Link firmware for the Spansion on-board debug solution:

Firmware Limitations


The firmware that makes the Spansion on-board debug solution J-Link compatible has some limitations in contrast to an original, industry leading SEGGER J-Link:

  • May be used with ARM Cortex-M based Spansion 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.
  • Due to limitations of the Spansion eval board PCBs, SWO cannot be supported by the on-board debug solution. In order to use SWO, an external J-Link connecting to the target CPU, is required.
  • No support is given.

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