Teet Tilk

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5 years, 3 months ago.

Without external LF oscillator

How can I configure nRF51-DK Mbed to work with internal low frequency RC oscillator instead of external 32kHz oscillator? My custom board doesn't have external low frequency oscillator. Documentation about oscillator configuration found from online was for previos versions and doesn't help with current version.

Question relating to:

Last updated: 27 Aug 2020
The nRF51 Development Kit is a single-board development kit for Bluetooth Smart, ANT and 2.4GHz proprietary applications using the nRF51 Series SoC. This kit supports both development for both nRF51822 …

1 Answer

Desmond Chen
5 years, 2 months ago.

Hi Teet,

You can use mbed.json to override the LF_CLOCK_SRC configuration, and use internal RC.

add this to mbed_app.json

"target_overrides": {
        "NRF51_DK": {
            "target.lf_clock_src": "NRF_LF_SRC_RC"
        }
    }

Please feel free to ask me any questions!

Desmond, team Mbed