How to use the internal 32.768k crystal oscillator for nrf5340

[Август]

How to use the internal 32.768k crystal oscillator for nrf5340？

NCS: V1.5.0

example: ncs1.5.0\v1.5.0\nrf\samples\peripheral\radio_test

Only HF no LF config.

[Jørgen Holmefjord]

Hi,

As far as I can see, the radio_test sample does not use the LFCLK, so there is no need to configure the LFSRC. Are you not able to run the sample on a board without the LF crystal?

Best regards,
Jørgen

[Август]

Hi,

Thank you.

Yes, I added a led, but I can’t see the led working.

ncs1.5.0\v1.5.0\nrf\samples\peripheral\radio_test

ncs1.5.0\v1.5.0\nrf\samples\nrf5340\empty_app_core

It works fine when I use 32.768khz crystal.

[Август]

It also doesn't work when I use the peripheral_uart example.

ncs1.5.0 \ v1.5.0 \ nrf \ samples \ bluetooth \ peripheral_uart

[Август]

Can you help me make the peripheral_uart example work using RC.

ncs1.5.0 \ v1.5.0 \ nrf \ samples \ bluetooth \ peripheral_uart

Thank you.

[Август]

Hi,

Thank you. I have solved the problem.

1. v1.5.0\nrf\samples\bluetooth\peripheral_uart\prj.conf

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

CONFIG_BT_SMP=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_500PPM=y

2. v1.5.0\zephyr\samples\bluetooth\hci_rpmsg\prj.conf

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

CONFIG_BT_SMP=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_500PPM=y