Device not connecting in boot loader mode

[ssc]

Hello ,

I am using nRF52832 controller in peripheral role. I have integrated Secure boot loader code. I am facing issue of mobile device is not getting connected to the DFU service in boot-loader.

When device is in Application  it is connected and operation is fine,but after entering DFU by triggering command from DFU service to enter boot-loader mobile does not get connected but device remains in boot-loader mode. SDK used is 15.2.0 . Secure bootloader example code from DFU section is used.

I am using Custom board with ready module integrated  of nrf52832 from RAYTAC (MDBT42Q-512KV2). Board has Power supply regulator on board. Input supply voltage 10 v to 30 v with 500 mA current rating. When i use supply input of 5 volt it works perfectly. But for 12 volts it gives me above error behavior. This issue is been faced after flashing secure boot-loader code. Without boot-loader code simple application works totally fine.

Thanks in advance.

[Edvin]

Are all the clock configurations in your bootloader and the application the same? Before you changed to NRF_CLOCK_LF_SRC_SYNTH in the bootloader, of course.

The settings I am asking about are:

NRF_SDH_CLOCK_LF_SRC
NRF_SDH_CLOCK_LF_RC_CTIV
NRF_SDH_CLOCK_LF_RC_TEMP_CTIV
NRF_SDH_CLOCK_LF_ACCURACY

Note that these are not the same as:

NRFX_CLOCK_CONFIG_LF_SRC. I am looking for the defines with "..._SDH_..."

Can you list these defines from the bootloader project and for the application project?

BR,

Edvin

[ssc]

Following were the clock configurations before the change in boot loader:

For Application:

NRF_SDH_CLOCK_LF_SRC = NRF_CLOCK_LF_SRC_SYNTH 
NRF_SDH_CLOCK_LF_RC_CTIV = NRF_CLOCK_LF_SRC_RC
NRF_SDH_CLOCK_LF_RC_TEMP=_CTIVNRF_CLOCK_LF_SRC_RC
NRF_SDH_CLOCK_LF_ACCURACY= NRF_CLOCK_LF_ACCURACY_20_PPM

For boot loader:

NRF_SDH_CLOCK_LF_SRC = NRF_CLOCK_LF_SRC_XTAL
NRF_SDH_CLOCK_LF_RC_CTIV = NRF_CLOCK_LF_SRC_RC
NRF_SDH_CLOCK_LF_RC_TEMP=_CTIVNRF_CLOCK_LF_SRC_RC
NRF_SDH_CLOCK_LF_ACCURACY= NRF_CLOCK_LF_ACCURACY_20_PPM

[Edvin]

Do you have an external XTAL? I was actually wondering what the values were. 

But if you used NRF_CLOCK_LF_SRC_XTAL, what is the value of the capacitors on your custom board (the ones connected between the XTAL and the nRF)? And what is the specs of the LFXTAL?

[ssc]

Edvin said:

Do you have an external XTAL? I was actually wondering what the values were. 

Yes i do have an external crystal ABS07-32.768kHz is used . 

Edvin said:

what is the value of the capacitors on your custom board (the ones connected between the XTAL and the nRF)

12pF

[Edvin]

Edvin said:

And what is the specs of the LFXTAL?

 12pF for the caps is correct if the internal capacity of the XTAL is 8pF. 

You can read about it here:

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52832.ps.v1.1%2Fclock.html&cp=4_2_0_18_1_3&anchor=concept_pln_z5y_2q

The capacitance on the capacitors should be:

C = 2xC_L - C_pin

C_L = capacitance on the XTAL

C_pin = 4 (nRF specification).

So on the DK, C_L = 8pF, so the capacitors should be:

C = 2x8-4 = 12pF

But it may not be the same for your capacitor. 

Also, please make sure you set the XTAL accuracy in sdk_config.h according to the accuracy on your XTAL from it's specification.

BR,

Edvin