bt_sdc_hci_driver: Entropy source device not ready and HCI driver open failed (-19) on nRF54L15

RE: bt_sdc_hci_driver: Entropy source device not ready and HCI driver open failed (-19) on nRF54L15

Hung Bui — Fri, 14 Nov 2025 11:03:25 GMT

Hi Mert,
I couldn't build your project here due to some device tree issue I think.

But I think it's important to make sure your DK can run a simple BLE application. My suggestion is to try downloading a fresh NCS SDK (latest version now is v3.1.1)

Please try to test with non _ns board. Have you gone through our academy courses ? https://academy.nordicsemi.com/

Please also try get hold of a 2nd board, just in case there could be a problem with the board you have.

RE: bt_sdc_hci_driver: Entropy source device not ready and HCI driver open failed (-19) on nRF54L15

mertpalaoglu1 — Fri, 14 Nov 2025 06:44:20 GMT

I am sorry for the late reply. Last week was my midterm week 😃

[quote userid="2121" url="~/f/nordic-q-a/125472/bt_sdc_hci_driver-entropy-source-device-not-ready-and-hci-driver-open-failed--19-on-nrf54l15/553671"]
Can you run any BLE sample in the SDK ? [/quote]

I tried to build "peripheral_lbs" sample from sdk. I also get these errors from it (it does not use any pwm, or the example had any .overlay, I was getting the error):

-- Found devicetree overlay: nrf54l15dk_nrf54l15_cpuapp.overlay
devicetree error: 'pinctrl-0' is marked as required in 'properties:' in C:/ncs/v3.0.2/zephyr/dts/bindings\pwm\nordic,nrf-pwm.yaml, but does not appear in <Node /soc/peripheral@50000000/pwm@d3000 in 'C
:/ncs/v3.0.2/zephyr/misc/empty_file.c'>
CMake Error at C:/ncs/v3.0.2/zephyr/cmake/modules/dts.cmake:305 (execute_process):
execute_process failed command indexes:

1: "Child return code: 1"

So I made an overlay file and disabled the &pwm20 node, It still gives the same error when building..

[quote userid="2121" url="~/f/nordic-q-a/125472/bt_sdc_hci_driver-entropy-source-device-not-ready-and-hci-driver-open-failed--19-on-nrf54l15/553671"]Could you provide a minimal project that we can reproduce the issue here? [/quote]

I am using nCS v3.0.2 and targeting the nrf54l15dk_nrf54l15_cpuapp_ns board. I am getting the error even with this slightly modified example:

Here is my project in minimal form at github: https://github.com/mertpalaoglu1/my_nRF_example

You can reproduce the issue here.

Again thanks for the replies and solutions in advance.

RE: bt_sdc_hci_driver: Entropy source device not ready and HCI driver open failed (-19) on nRF54L15

Hung Bui — Fri, 07 Nov 2025 12:57:16 GMT

Hi Mert,
The error suggests that the controller was not ready when booting up. This is quite strange as the nRF54L doesn't have a dedicated radio core that run the controller.

Can you run any BLE sample in the SDK ?

Could you provide a minimal project that we can reproduce the issue here?