BLE on nrf54l10 custom board not working

RE: BLE on nrf54l10 custom board not working

Asbjørn — Thu, 18 Dec 2025 20:54:49 GMT

Hi Alexandra,

Difficult to say based on the information here now why it halts.

Have you tried adding some breakpoints and see exactly which step after CONFIG_BT=y that breaks it?

I assume the stack size adjustments work fine for when you don't enable CONFIG_BT=y?

Have you built one of the code example in the NCS with nRF54L10 as target, are you able to get that running? For example the HRT service.

Any chance you could upload the code you are working on if we make this a private case?

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Best regards

Asbjørn

RE: BLE on nrf54l10 custom board not working

Alexandra L — Thu, 18 Dec 2025 16:03:03 GMT

hello, thank you for your answer

i have tried to, instead using uart, just try to set a gpio to understand if the problem was from uart. A simple code that only set the gpio.

Without the CONFIG_BT=y, it worked. When i turned on the CONFIG_BT, the program did not set the gpio.

this is my prj.conf

CONFIG_BT=y

# STEP 2 - Set the Bluetooth LE device name

#ONFIG_BT_DEVICE_NAME="Nordic_Beacon"

# Increase stack size for the main thread and System Workqueue

#CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048

#CONFIG_MAIN_STACK_SIZE=2048

#to disable external low frequency clock

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_XTAL=n

the other configurations are on my boards prj.conf file which is the nrf54l10 available by zephyr, nordic.

On the osciloscope i could see the external clock, high frequency, of 32Mhz, the same as the development kit, working.

I also have added this on my dtsi file

&clock {

status = "okay";

hfclk {

source = "external";

};

lfclk {

source = "rc"; /* OK if no 32k crystal */

};

Is there any configuration missing? It is because I am using nrf54l10 and not nrf5415 so I need to change anything regarding space? I am not understanding where the problem can be from.

RE: BLE on nrf54l10 custom board not working

Asbjørn — Wed, 17 Dec 2025 15:56:30 GMT

Hello Alexandra,

With the CONFIG_BT=Y you enable the Bluetooth stack and it takes control over the clock sources, or at least it might reconfigure the clock sources. By that I mean it could be switching them off unintentionally in your case.

You should check if the HFINT is switched on or requested in your main before doing the UART prints, wait for the HFINT.READY event and then proceed with the print. If you never get to the print, the clock isn't ON.

Have you tried any of the bluetooth examples in our SDK? There's a peripheral UART service code example that also prints UART, but have the UART service as part of the bleutooth service. https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/samples/bluetooth/peripheral_uart/README.html

Q1: In your case, do you see that the bluetooth functionality works? Are you able to see advertising?

Q2: Have you tried debugging the startup and see where it gets stuck when you have enabled CONFIG_BT=y?

Best regards

Asbjørn