NCS 1.9.0 usage issues

[Hannibalhz]

Dear Nordic Engineers

I used NRF CONNECT SDK on NRF52840,I  have some questions,Please help me.

1、I used  the buttons module of the Common Application Framework ,but I found that all I/O can only be configured as  pull-up or pull-down in the code.I hope that the pull-up or pull-down of each I/O can be configured individually.Please tell me how to achieve it.

2、Can I use the high frequency clocks as a clock source for interrupts?If so,what should I do in the code to configure?

Best regards.

[Kenneth]

I was looking at this example https://github.com/nrfconnect/sdk-nrf/tree/v1.8.0/samples/caf, and it looks like the pull-up/down configuration are not set by the caf_buttons module.

The caf_module only define which pins to use, the pull configuration is set in the board .dts file, for instance:
pins used by caf: https://github.com/nrfconnect/sdk-nrf/blob/v1.8.0/samples/caf/configuration/nrf52840dk_nrf52840/buttons_def.h 
configuration of pins: https://github.com/nrfconnect/sdk-zephyr/blob/main/boards/arm/nrf52840dk_nrf52840/nrf52840dk_nrf52840.dts 

So if you want to change pull configuration you can for instance add changes in the overlay file:
https://github.com/nrfconnect/sdk-nrf/blob/v1.8.0/samples/caf/boards/nrf52840dk_nrf52840.overlay 

Please also refer to the documentation for the caf buttons module on configuration options:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/libraries/caf/buttons.html 

Best regards,
Kenneth

[Hannibalhz]

Dear Kenneth

Thanks for your answer.

Please help to answer my second qusetion.

2、Can I use the high frequency clocks as a clock source for interrupts?If so,what should I do in the code to configure?

Best regards.

[Kenneth]

I do no understand the question, typically you have a high frequency clock used for running MCU and Radio, and you have a low frequency clock for low power operation and wakeup at certain intervals.

Best regards,
Kenneth