Using soft device on custom board with nRF52840

RE: Using soft device on custom board with nRF52840

bojan — Tue, 04 Jun 2019 09:49:34 GMT

Hey awneil, yes, I've read through the linked post. The same post was suggested by Ali Rumane. I configured the code properly inside sdk.config.h (section SoftDevice clock configuration) and everything works great now! Once again, thanks for your responsiveness and great help!

Cheers!

RE: Using soft device on custom board with nRF52840

awneil — Tue, 04 Jun 2019 09:46:08 GMT

You're welcome!

You might want to give feedback to the module manufacturer that their documentation could be more helpful in explaining the implications of choosing to omit the external LF clock...

You might want to give feedback to Nordic on how this might be better documented ...

RE: Using soft device on custom board with nRF52840

awneil — Tue, 04 Jun 2019 09:39:47 GMT

Did you read the linked post?

Yes, the external 32KHz is optional but, if you opt to omit it, then you have to configure your code accordingly.

RE: Using soft device on custom board with nRF52840

bojan — Tue, 04 Jun 2019 09:39:30 GMT

Hello Ali Rumane, thank you very much for your pointer! It was really useful for me! Indeed, I had the issue with SoftDevice clock configuration in sdk_config.h file. With the following settings everything works great:

// </h> 
//==========================================================

// <h> Clock - SoftDevice clock configuration

//==========================================================
// <o> NRF_SDH_CLOCK_LF_SRC  - SoftDevice clock source.
 
// <0=> NRF_CLOCK_LF_SRC_RC 
// <1=> NRF_CLOCK_LF_SRC_XTAL 
// <2=> NRF_CLOCK_LF_SRC_SYNTH 

#ifndef NRF_SDH_CLOCK_LF_SRC
#define NRF_SDH_CLOCK_LF_SRC 0
#endif

// <o> NRF_SDH_CLOCK_LF_RC_CTIV - SoftDevice calibration timer interval. 
#ifndef NRF_SDH_CLOCK_LF_RC_CTIV
#define NRF_SDH_CLOCK_LF_RC_CTIV 16
#endif

// <o> NRF_SDH_CLOCK_LF_RC_TEMP_CTIV - SoftDevice calibration timer interval under constant temperature. 
// <i> How often (in number of calibration intervals) the RC oscillator shall be calibrated
// <i>  if the temperature has not changed.

#ifndef NRF_SDH_CLOCK_LF_RC_TEMP_CTIV
#define NRF_SDH_CLOCK_LF_RC_TEMP_CTIV 2
#endif

// <o> NRF_SDH_CLOCK_LF_ACCURACY  - External clock accuracy used in the LL to compute timing.
 
// <0=> NRF_CLOCK_LF_ACCURACY_250_PPM 
// <1=> NRF_CLOCK_LF_ACCURACY_500_PPM 
// <2=> NRF_CLOCK_LF_ACCURACY_150_PPM 
// <3=> NRF_CLOCK_LF_ACCURACY_100_PPM 
// <4=> NRF_CLOCK_LF_ACCURACY_75_PPM 
// <5=> NRF_CLOCK_LF_ACCURACY_50_PPM 
// <6=> NRF_CLOCK_LF_ACCURACY_30_PPM 
// <7=> NRF_CLOCK_LF_ACCURACY_20_PPM 
// <8=> NRF_CLOCK_LF_ACCURACY_10_PPM 
// <9=> NRF_CLOCK_LF_ACCURACY_5_PPM 
// <10=> NRF_CLOCK_LF_ACCURACY_2_PPM 
// <11=> NRF_CLOCK_LF_ACCURACY_1_PPM 

#ifndef NRF_SDH_CLOCK_LF_ACCURACY
#define NRF_SDH_CLOCK_LF_ACCURACY 1
#endif

// </h>

Thank you both, awneil, Ali Rumane, for your great feedbacks. I can now move forward!

Cheers,

Bojan

RE: Using soft device on custom board with nRF52840

bojan — Tue, 04 Jun 2019 09:13:05 GMT

Hi awneil, thanks for replying. I am using BL654 module on my custom board. Accordng to chapter 5.17 on page 34 (link), external 32.768KHz oscillator is optional (not required for normal BL654 module operation).

RE: Using soft device on custom board with nRF52840

Ali Rumane — Tue, 04 Jun 2019 09:10:41 GMT

Hi,

Did you set Low Frequency Clock settings correctly?

I faced similar issue with BLE examples which was solved by setting clock source & settings correctly.

Regards

RE: Using soft device on custom board with nRF52840

awneil — Tue, 04 Jun 2019 09:07:42 GMT

Does your custom board have a 32KHz crystal ?

https://devzone.nordicsemi.com/f/nordic-q-a/46564/error-133-0x85-gatt-error-on-nrf52840/185362#185362