connection problem with nrf52832

RE: connection problem with nrf52832

Berker — Mon, 15 Oct 2018 08:27:43 GMT

Thanks

You're right, DK already intstalled with an example.

RE: connection problem with nrf52832

Sigurd — Mon, 15 Oct 2018 08:18:56 GMT

Then the DK was probably already flashed with the ble_blinky example before you programmed the custom board.

When the custom board is powered, the programmer on the DK will detect the supply voltage of the custom board and program/debug the target chip on the custom board instead of the on-board nRF52832.

RE: connection problem with nrf52832

Berker — Fri, 12 Oct 2018 12:44:22 GMT

Ok,thanks

I will try some clock configurations.

Maybe another topic,but if you can help, I will be pleased

I use DK while programming custom board. I try loading ble_blinky example to custom board,but DK also loaded with blinky_example. Mobile app shows 2 advertising devices one custom board,another one DK. I only want to load custom one.

How can i solve this?

Best Regards

RE: connection problem with nrf52832

Sigurd — Fri, 12 Oct 2018 11:39:43 GMT

[quote userid="74430" url="~/f/nordic-q-a/39341/connection-problem-with-nrf52832/152675"]Is there a wrong thing?[/quote]

No, that is OK. You can use the internal 32.768 kHz RC oscillator, but it's important that it's correctly configured. (NRF_SDH_CLOCK_LF_SRC 0, NRF_SDH_CLOCK_LF_RC_CTIV 16, NRF_SDH_CLOCK_LF_RC_TEMP_CTIV 2 and NRF_SDH_CLOCK_LF_ACCURACY 1).

RE: connection problem with nrf52832

Berker — Fri, 12 Oct 2018 11:35:40 GMT

I didn't insert 32.768kHz crystal on custom pcb. As i know, that for RTC. I only insert 32MHz crystal through XC1/XC2 pins. 32.768kHz pins P0/P1 used for another purpose on custom pcb. Is there a wrong thing?

RE: connection problem with nrf52832

Sigurd — Fri, 12 Oct 2018 11:25:06 GMT

[quote userid="74430" url="~/f/nordic-q-a/39341/connection-problem-with-nrf52832/152633"]The problem is related with my 32MHz oscillator? Or what? [/quote]

If changing the value of NRF_SDH_CLOCK_LF_SRC from 1 to 0 worked, then this indicates an issue with the external 32.768 kHz crystal. It could be caused by wrong values of the load capacitors(C11/C12), bad soldering and/or incorrect value of the specified clock accuracy.

[quote userid="74430" url="~/f/nordic-q-a/39341/connection-problem-with-nrf52832/152633"]And sometimes connection not bonded, the reason of this RSSI? or about your reply? [/quote]

This could also be caused by issues with the 32.768 kHz crystal.

If you want us to review your custom board design, I would recommend that you create a new case, where you upload the PCB layout/gerber files and schematic, and we can maybe help with some improvements to the design.

RE: connection problem with nrf52832

Berker — Fri, 12 Oct 2018 09:06:42 GMT

Hi Sigurd,

thanks for this useful reply.

Adv interval fixed now and 40ms as expected. Also connection established most of the time and i can blink led.

The problem is related with my 32MHz oscillator? Or what?

[quote userid="15146" url="~/f/nordic-q-a/39341/connection-problem-with-nrf52832/152611"]What RSSI value did you measure on the custom board?[/quote]

RSSI is not good, -70,80dBm in about 20-30cm distance. Is this related my antenna and board design,is it true?

And sometimes connection not bonded, the reason of this RSSI? or about your reply?

Thanks

RE: connection problem with nrf52832

Sigurd — Fri, 12 Oct 2018 08:07:25 GMT

Hi,

What RSSI value did you measure on the custom board?

What clock source are you using for the SoftDevice?

Could you try this configuration for the LF clock source: (from sdk_config.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

RE: connection problem with nrf52832

Berker — Fri, 12 Oct 2018 07:40:13 GMT

Hi,

I want to give more detail, explain again. I'm still haven't any solution.

I use blee_app_blinky example to test my custom board. This example works in DK as expected.

#define APP_ADV_INTERVAL 64

This coressponds 40ms advertisiment. In the mobile side, i can see 40ms on nRF connect app,if i use DK.

But, with same example and custom board, i see this interval as about 700-800ms. I don't understand this.

Also, app doesn't work beacuse of connection not bonded and connection is not established .

Best Regards