NRF52810 softdevice issue on custom Board

[Swapnil Karkare]

Hi Everyone,

We are using NRF52810 with latest nRF5_SDK_16.0.0 and s112_nrf52_7.0.1_softdevice. We are able to program with ble_app_UART example on our prototype,

but BLE is not advertising. here are some snapshots of our project configuration.

APP_TIMER_V2
APP_TIMER_V2_RTC1_ENABLED
DEVELOP_IN_NRF52832
BOARD_PCA10040
CONFIG_GPIO_AS_PINRESET
FLOAT_ABI_SOFT
NRF52810_XXAA
NRF52_PAN_74
NRFX_COREDEP_DELAY_US_LOOP_CYCLES=3
NRF_SD_BLE_API_VERSION=7
S112
SOFTDEVICE_PRESENT

this are the processor configurations.

I have also changes the clock frequency configuration.

I am able to print "UART START " on above example. But facing BLE advertising issue. We get "NRF_BREAKPOINT_COND;" error some time.

Please give suggestion how can we start BLE adverting.

Thank you.

[Swapnil Karkare]

Hi,

We are using LF clock frequency for BLE UART advertising program testing. The used External crystal frequency  24MHz connected at XC1 and XC2 pins. It Didn't work.

We also checked with 16MHz Crystal.

We removed 32MHz crystal from PCA10040 Evalution kit and assembled on our prototype and it started advertising. 

All testing is done on LF clock configuration.

//==========================================================

// <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

Does NRF allow use of different Crystals frequency apart from 32MHz?

Is there dependencies on External crystal though we used Internal oscillator?

[Vidar Berg]

Hi,

You must have an external 32Mhz crystal with a tolerance of +-40ppm or better if you're going to use BLE. It's not optional like the LF crystal is.

[Swapnil Karkare]

Hi,

Does this mean BLE soft device has some clock settings which assumes 32MHz crystal connected to the chip?

I am asking this because now it is BOM change for us. will have to forward this to hardware team.

Thanks.

[Vidar Berg]

Hi,

The oscillator is designed for 32M. You have to update the BOM unfortunately. Please use our reference design in the PS as a reference. 

[Swapnil Karkare]

Thank you very much for Update. :-)