Error programming Thingy 91X: slot_index_primary is required

[andersr]

I have rebuilt the sample app at_client using VS Code (Mac)
nRF Connect SDK v2.6.0 and Toolchain v2.6.0
Board target: thingy91_nrf9151
Snippets: nrf91-modem-trace-uart

I am using nRF Connect for Desktop -> Programmer v4.6.2 to program the device
File: at_client/build/zephyr/dfu_application.zip

When programming I get the following failure:
Message: Failed, Error parsing multi-image file entry: slot_index_primary is required.

Same result if I try to use command line.

Full log:
2025-07-20T21:01:38.782Z INFO Device connected with the serial number THINGY91X_941D1C15D72
2025-07-20T21:01:45.430Z INFO Getting serial port options from the persistent store for THINGY91X_941D1C15D72.pc-nrfconnect-programmer
2025-07-20T21:01:45.431Z INFO Device connected with the serial number THINGY91X_941D1C15D72
2025-07-20T21:01:45.431Z DEBUG Sending event "programmer: device connected"
2025-07-20T21:01:45.657Z INFO Getting serial port options from the persistent store for THINGY91X_941D1C15D72.pc-nrfconnect-programmer
2025-07-20T21:01:45.657Z DEBUG Sending event "programmer: device connected"
2025-07-20T21:01:45.664Z INFO Getting serial port options from the persistent store for THINGY91X_941D1C15D72.pc-nrfconnect-programmer
2025-07-20T21:01:45.664Z DEBUG Sending event "programmer: device connected"
2025-07-20T21:01:56.082Z INFO Selecting device with the serial number THINGY91X_941D1C15D72
2025-07-20T21:01:56.089Z DEBUG Sending event "programmer: running nrfutil device"
2025-07-20T21:01:56.210Z INFO Selected device with the serial number THINGY91X_941D1C15D72
2025-07-20T21:01:56.211Z DEBUG Sending event "programmer: device selected"
2025-07-20T21:02:01.650Z INFO Checking ZIP file: /Users/anders/Sources/thingy91x/at_client/build/zephyr/dfu_application.zip
2025-07-20T21:02:01.650Z INFO File was last modified at 7/18/2025, 12:36:15 PM
2025-07-20T21:02:07.003Z INFO Modem DFU starts to write...
2025-07-20T21:02:07.003Z INFO Writing /Users/anders/Sources/nrf52840dk/at_client/build/zephyr/dfu_application.zip to device THINGY91X_941D1C15D72
2025-07-20T21:02:07.006Z DEBUG Sending event "programmer: running nrfutil device"
2025-07-20T21:02:07.129Z ERROR Error: Failed with exit code 1.
One or more program tasks failed:
* THINGY91X_941D1C15D72: Error parsing multi-image file entry: slot_index_primary is required (FileOpenFailed)

Message: Failed, Error parsing multi-image file entry: slot_index_primary is required.
2025-07-20T21:02:07.129Z ERROR Modem DFU failed with error: Error: Failed with exit code 1.
One or more program tasks failed:
* THINGY91X_941D1C15D72: Error parsing multi-image file entry: slot_index_primary is required (FileOpenFailed)

Message: Failed, Error parsing multi-image file entry: slot_index_primary is required.

[andersr]

Correction: build target thingy91_nrf9151_ns

[dejans]

Hi,

Are you able to build the sample from command line (with and without the snippet)?

Best regards,
Dejan

[andersr]

Pulled new sample project to /opt/tst/at/

This gives exact same error.

[andersr]

I do suspect this has something to do with configuration. The prototype is found in 

<zephyr/drivers/timer/system_timer.h> and I see the implementation in the drivers in zephyr/drivers/timer/*.c files.

Namely nrf_rtc_timer.c and nrf_grtc_timer.c (if one of those is appropriate for the platform).

Question is if timer driver is supported by the platform and what configs includes the timer implementation files in the build.

[andersr]

Since implementation is in nrf_rtc_timer I did the following
rtc0 or rtc1 is not included in thingy91_nrf9151_ns.dts, so I added app.overlay with

&rtc0 {
status = "okay";
};

And added
CONFIG_NRF_RTC_TIMER=y
To my prj.conf file.

Still same error: undefined reference to `sys_clock_elapsed'

So the question remains:
How do I get nrf_rtc_timer.c included in my build. (If that's the implementation I need).

[dejans]

Hi,

Can you try to program thingy91x_at_client_2025-05-08_3bfc4657.zip (found in img_dfu_zip folder)?
You can use "nrfutil device program" to flash zip firmware. You can find more information in updating application firmware on nrf9151.

Best regards,
Dejan

[andersr]

I cannot find this file on my Mac. Nor the folder. Please give full path or web location.

Does this image have nrf91-modem-uart-trace enabled?

[dejans]

Hi,

Please find precompiled application and modem firmware images on the Thingy91:X Downloads webpage.

Debug builds in the debug folder have tracing enabled, other builds do not have traces enabled. Modem shell and SLM builds have UART modem tracing enabled.

Best regards,
Dejan

[andersr]

That loads. But I expected that to work.

I think there is some confusion here. My original problem of loading an image to my Thingy91X was resolved by changing my SDK and Toolchain to v3.0.2 building the plain at_client.

A new issue appeared when I failed to build at_client with the nrf91-modem-uart-trace snippet in the same sandbox. This also failed when moving my sandbox to a shorter path. I need this for my Thingy91X to work with nRF Cellular Monitor v2.4.4. I should probably raise a new issue on this.

I have tested all of the prebuilt zip files and none of them seem to work with the Cellular Monitor. Regardless I would like to be able to build the Thingy with nrf91-modem-uart-trace snippet myself so I can make any changes needed and possibly adapt some of the code to my own application.

Since tis is a separate issue I would suggest closing this issue and I will raise a new issue on building at_client with nrf91-modem-uart-trace snippet for Thingy 91X.

[jtrovato]

Did you ever sort out your new issue? I am experiencing the same thing on my Thing91X when I tried to enable the UART modem trace snippet.