The LPC55S69-EVK board comes on-board debug probe. The board includes the LPC4322JET100 device which acts like NXP LPC-Link2 debug probe:

LPC4322JET100 on LPC55S69-EVK

But it is easily possible to use the board with an external debug probe or re-program the onboard one as a SEGGER J-Link debug probe.

Compared to the NXP OpenSDA circuit on other boards (Freedom, Tower) this is a much more powerful and faster debug interface. While the LPC-Link2 circuit can be found embedded on evaluation boards, it is available for $20 as a standalone probe.

External Debug Probes

The board features a standard 10-pin ARM SWD/JTAG header: without any extra jumper settings, it is possible to attach an external debug probe of choice, e.g. a SEGGER J-Link, a NXP LPC-Link2 or P&E Multilink.

Debugging with P&E Multilink Universal FX

Debugging with SEGGER J-Link EDU Mini

Debugging with external LPC-Link2

Reprogramming the NXP LPC-Link2 as SEGGER J-Link

As another option it is possible to use the on-board (or off-board) LPC-Link2 as a SEGGER J-Link (https://www.segger.com/products/debug-probes/j-link/models/other-j-links/lpc-link-2/).

💡 The steps described here apply for an external LPC-Link2 debug probe too. Keep in mind the SEGGER license agreement and that the firmware only allows debugging NXP LPC parts and no other devices).

1. Download LPCScrypt from the NXP web site and run the installer. Remember the installation path (default for my version on Windows: C:\nxp\LPCScrypt_2.1.0_842)
2. Download the SEGGER NXP LPCXpresso On-Board Firmware from the SEGGER website (Note: for an external LPC-Link2 probe use the NXP LPC-Link2 file)
   

   SEGGER NXP LPCXpresso On-Board Firmware

3. The downloaded firmware file is named ‘Firmware_JLink_LPCXpressoV2.bin’. Place that file into the installation directory of the installed LPCScrypt:
   <lpcscrypt>\probe_firmware\LPCXpressoV2
4. The above directories already contain an (older) version of the firmware. Make sure that the new SEGGER firmware file matches the name of the already installed ones:
   

   Renamed firmware files

5. Power the board with the DFU (Device Firmware Update) Jumper installed.
   

   DFU Jumper Installed

6. Run the script ‘program_JLINK.cmd’ located in the <install>\scripts folder:
   

   Running J-Link Script

7. Remove the DFU jumper and re-power the board
8. The board now has a J-Link on it 🙂

I can now use it as an external J-Link debug probe, e.g. from the MCUXpresso IDE. Having a J-Link gives the advantage of using SEGGER RTT or SEGGER SystemViewer.

💡 To reprogram the board back to the LPC-Link2/CMSIS-DAP firmware, run the ‘program_CMSIS.cmd’ batch file.

Summary

I like the fact that the board offers many different debug options: that way I can choose the one which fits best my needs (price, performance, features). Looking at the board/schematics it seems it would be possible to use the on-board probe debugging another board, but that would need at least soldering an SWD header. With the price of $20 for an external LPC-Link2 or a SEGGER J-Link EDU Mini I think this is not really worth the effort.

Happy Linking 🙂

Links

• LPC-Link2 Debug Probe: https://www.nxp.com/support/developer-resources/software-development-tools/lpc-developer-resources-/lpc-microcontroller-utilities/lpc-link2:OM13054
• P&E Multilink Universal Debug Probe: http://www.pemicro.com/multilink/
• SEGGER J-Link EDU Mini Debug Probe: https://www.segger.com/products/debug-probes/j-link/models/j-link-edu-mini/
• Load J-Link driver on a LPC-Link2: https://www.segger.com/products/debug-probes/j-link/models/other-j-links/lpc-link-2/
• LPCScrypt: https://www.nxp.com/support/developer-resources/software-development-tools/lpc-developer-resources-/lpc-microcontroller-utilities/lpcscrypt-v2.1.0:LPCSCRYPT?&tid=vanLPCSCRYPT
• SEGGER LPC-Link2 Firmware: https://www.segger.com/downloads/jlink/