Hello fellow mailinglist members,

I'm currently trying to get the samples "hci_uart" and "hci_usb" working on a laird654 module / Laird DVK-BL654-1.0 (nrf52480)
Both samples work on the nrf52480DK (pca10056) but refuse to work on the Laird654 module.

Regarding hci_uart I would like to transfer know-how I gained at the apache mynemt-os project: 
I got the respective sample from the apache newt project "blehci" working after configuring the nrf52480 to use the synthesized clock and modify the sleep clock accuracy:
In the newt world this was achieved via setting syscfg=XTAL_32768=0 syscfg=XTAL_32768_SYNTH=1:BLE_XTAL_SETTLE_TIME=0 syscfg=BLE_LL_OUR_SCA=250:BLE_LL_MASTER_SCA=1
I know these settings are newt specific but how could I achieve this for the zephyr samples ? 

Looking forward to your reply.

Best regards

Hello Matthias,

By default the BL654 DVK does not connect the external 32 kHz clock.  In zephyr, the NRF52840 board files are setup to use the external 32 kHz clock.
You have 2 options:

1. Follow the instructions in teh BL654 DVK user guide to connect the external 32 kHz clock
2. Create a custom board file (which you should do anyway) and enable the internal 32 kHz RC oscillator