Nordic Semiconductor nRF54H20

The Nordic Semiconductor nRF54H20 are ultra low-power multiprotocol wireless System-on-Chip (SoC) supporting Bluetooth Low Energy, Bluetooth mesh, Thread, and Matter technologies.

STM tracing

The NRF54H20 includes a STM. It can be used for system tracing.

Minimum requirements

• J-Trace Pro V3 or later
• Trace pinout on board
• Target application that initializes Arm Coresight and configures STM to send data (recommended STM trace ID is 0x40)
• J-Link software V7.94i or later
• nRF54H20-DK eval board
• Python V3.10 installed

Example setup

• Download the following example setup and unzip it: File:nRF54 STM ExampleSetup.zip
• Make sure your target application is already flashed which fulfills the requirements above.
• Open STM_Trace_TestClient.py and leave the launched window open
• Open a terminal from the unzipped folder
• Call the JLink.exe file with the following command line: -device Cortex-M33 -JLinkScriptFile .\nRF54_Connect.JLinkScript -if SWD -speed 4000 -CommandFile .\nRF54_Command.jlink
  • On Linux or macOS systems replace the JLink.exe with the host specific executable for the J-Link Commander
• The raw STM data from the target device will now be stored in the STMData.bin file
• To stop the recording simply type q in the J-Link Commander and press enter

Capture with Nordic nrfutil

It is also possible to capture the stream with Nordics nrfutil tool.

Installation guides can be found here:

• https://docs.nordicsemi.com/bundle/nrfutil/page/guides/installing.html
• https://docs.nordicsemi.com/bundle/nrfutil/page/guides/installing_commands.html

The required command line call is: nrfutil trace stm --input-jtrace-serial-number <J-Trace serial number> --stdout ascii

Simply replace <J-Trace serial number> with your actual J-Trace Pro serial number.

If everything was set up correctly you should see the received STM printf data displayed in the terminal.