Peripheral Registers Not Visible in Keil Debug Session (NRF52840)

RE: Peripheral Registers Not Visible in Keil Debug Session (NRF52840)

Simonr — Fri, 24 Jul 2026 12:03:12 GMT

Hi Rani

If you're new to the Nordic development scene, I would strongly advice against using the nRF5 SDK and Keil, as the SDK supporting Keil at this point is very old and only in maintenance mode, with no new features being planned. Is there a specific reason you're using Keil and the nRF5 SDK for development? See the post here for details: nRF Connect SDK and nRF5 SDK statement

For new designs and especially engineers new to the Nordic scene, we strongly recommend starting out with the nRF Connect SDK, which is the stable and up to date version we recommend for development. We have great introductory courses and documentation available to get you started with it. https://academy.nordicsemi.com/courses/nrf-connect-sdk-fundamentals/

Best regards,

Simon

RE: Peripheral Registers Not Visible in Keil Debug Session (NRF52840)

Rani0 — Tue, 21 Jul 2026 05:32:56 GMT

Hi,

I'm new to Nordic development and this is my first time using an nRF52840 with Keil MDK. I can see the CPU registers (R0–R15, xPSR, etc.) and the Core Peripherals in the Registers window, but I cannot see the nRF52840 peripheral registers (GPIO, SPIM, TIMER, UARTE, SAADC, etc.) in the System Viewer.

My setup:

MCU: nRF52840_xxAA
IDE: Keil μVision 5.43.1
Debugger: J-Link
Nordic Device Family Pack: 8.44.1 (also tested 8.40)
ARM CMSIS Pack: 5.8

I verified that the nrf52840.svd file is present in the Nordic Device Family Pack, and I also tried loading the SVD manually through View → System Viewer, but only Core Peripherals are shown.

The same example project works correctly in Segger Embedded Studio, where I can view all peripheral registers without any issues.

Has anyone seen this issue with recent Keil/Nordic pack versions? Is there any additional configuration required to make the nRF52840 peripheral registers appear in the debugger?

Thanks in advance for any guidance. I'm still getting familiar with the Nordic/Keil environment.

RE: Peripheral Registers Not Visible in Keil Debug Session (NRF52840)

tesc — Fri, 17 Jul 2026 13:54:10 GMT

Hi,

For Keil, the MDK is installed through the use of Packs. If you are able to build an SDK sample for the nRF52840, then you should most likely already have the correct Pack installed for the nRF52840. Otherwise the build is expected to fail, or at least you should have gotten an error or warning when opening the project. Please double check still that the packs are installed and updated, and/or that you are able to install/update, before you try again. Please also check that you have a valid Keil License (otherwise some functionality is not available.)

Unfortunately, I was unable to check today in Keil uVision whether or not I could reproduce what you see. If needed, this is hopefully something we can check in our end next week. Let us know if you still do not manage to make it work.

Have you previously seen the peripheral registers in the Keil debugger, with an nRF5 SDK project and an nRF device? Or, is this the first time you do this with an nRF device?

Please note that if you are working on a new project, our recommendation is to use the new nRF Connect SDK, rather than the older and now in maintenance mode nRF5 SDK. For details, please se our nRF Connect SDK and nRF5 SDK statement. To be honest, the last time I debugged a project in Keil is so long ago I cannot remember how peripheral registers were accessed, if at all.

Regards,
Terje

RE: Peripheral Registers Not Visible in Keil Debug Session (NRF52840)

Kristian R — Fri, 17 Jul 2026 11:12:21 GMT

Hi!

I don't know for the nRF5 SDK, but for the NCS (zephyr-based) installation, the SVD file exists in e.g.:

/opt/nordic/ncs/v3.4.0/modules/hal/nordic/nrfx/bsp/stable/mdk/nrf52840.svd

You could take a look at this file: https://github.com/nrfconnect/sdk-hal_nordic/blob/main/nrfx/mdk/nrf52840.svd ,
I believe it is the same.

Regards,

Kristian from the VSCode extension developer team