https://devzone.nordicsemi.com/f/nordic-q-a/48715/nrf52-softdevice-stuck-without-external-low-frequency-clock-sourceHi, I have developed custom nrf52832 board without external low frequency clock source. So with that configuration I got problem when try to connect it through nRF MESH app. As I found issue come with the soft device. So I add 32.768kHz crystalen-USTelligent Community 13Tue, 18 Jun 2019 11:14:31 GMThttps://devzone.nordicsemi.com/thread/193395?ContentTypeID=1Tue, 18 Jun 2019 11:14:31 GMT137ad170-7792-4731-bb38-c0d22fbe4515:bf1d7c75-9271-4b9e-b1e9-fc4f61c8cc49haakonsh<p>Yes, you can use the LF RC oscilator as the LF source, but you need to set the accuracy to 500ppm, otherwise, you will not be able to have BLE communication.&nbsp;<br /><br />You need to call&nbsp;<a title="sd_softdevice_enable" href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v6.1.0/group___n_r_f___s_d_m___f_u_n_c_t_i_o_n_s.html?cp=3_4_1_2_2_8_2_1#ga420235cbdf6b0746ce86af3cfd0ec055">sd_softdevice_enable</a>&nbsp;with a correct&nbsp;<a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v6.1.0/structnrf__clock__lf__cfg__t.html">nrf_clock_lf_cfg_t</a>&nbsp;config.<br /><br />Set .accuracy to&nbsp;<a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v6.1.0/group___n_r_f___c_l_o_c_k___l_f___a_c_c_u_r_a_c_y.html#ga4abbe889ab90f5a8da00fe8175227ff7">NRF_CLOCK_LF_ACCURACY_500_PPM</a>, see&nbsp;<a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v6.1.0/group___n_r_f___c_l_o_c_k___l_f___a_c_c_u_r_a_c_y.html">Clock accuracy</a><span>.</span></p> <p><span>Set .source to <a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v6.1.0/group___n_r_f___c_l_o_c_k___l_f___s_r_c.html#gac5af0958064c212f19db190b8ad1e7e6">NRF_CLOCK_LF_SRC_RC</a>, see&nbsp;<a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v6.1.0/group___n_r_f___c_l_o_c_k___l_f___s_r_c.html">Possible LFCLK oscillator sources</a>.</span></p> <p><span>Set .rc_temp_ctiv to 0.</span></p> <p><span>Set .rc_ctiv to 16.</span></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/193391?ContentTypeID=1Tue, 18 Jun 2019 11:08:07 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e4d3bbf2-fd83-4d41-b902-6613883dc8c4awneil<p><a href="https://devzone.nordicsemi.com/f/nordic-q-a/46564/error-133-0x85-gatt-error-on-nrf52840/185362#185362">https://devzone.nordicsemi.com/f/nordic-q-a/46564/error-133-0x85-gatt-error-on-nrf52840/185362#185362</a></p><div style="clear:both;"></div>