Tweak ble_app_beacon to minimal current

[M]

Hi. Didn't find an exact answer for my question. I'm using the ble_app_beacon example on my custom board based on nrf51822. While powering it from a coin battery, I measure 200-300uA consumption. What can I add/change in this example to make it consume the least power possible (few uA between advertising transmissions)? Thanks.

[Stian Røed Hafskjold]

Okay, the LF_SYNTH probably explains it. It consumes quite a lot of current since it requires the HF clk to be running. You should use the internal LFRC clock instead if you don't have have a crystal. Change the clock config variable to use NRF_CLOCK_LF_SRC_RC when initializing the softdevice. The recommended configuration for NRF_CLOCK_LF_SRC_RC on nRF52 is rc_ctiv=16 and rc_temp_ctiv=2.

And you should probably move the sd_ble_gap_tx_power_set() to after the ble_stack_init() in main, so that the SD is initialized before you use any sd-calls.

[M]

Thank you, Stian. Your suggestion did the trick.