Zephyr tick QIAA vs CKAA

[robonordic]

We built a prototype board using the nrf52840 QIAA package, then developed a production board using the CKAA package. For some reason the Zephyr system tick is about 5x slower on the CKAA chip. Even the Zephyr "blinky" sample blinks the led 5x slower on the CKAA chip vs the QIAA. Is there a configuration setting for this?

[Amanda Hsieh]

Hi, 

Which version of NCS are you using? Does is also happen to the latest version?

Regards,
Amanda H.

[robonordic]

Found out that the new board with the CKAA package does not have a 32KHz external oscillator and I needed to switch to the internal one. This is not well documented, but found the answer here:

 nRF5x support within the Zephyr Project RTOS 

The magic incantation for Zephyr is:

CONFIG_CLOCK_CONTROL_NRF5_K32SRC_RC=y

CONFIG_CLOCK_CONTROL_NRF5_K32SRC_250PPM=y

[Amanda Hsieh]

Happy to know the issue is fixed. 

-Aamdna H.