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]

Hello,

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.

 What does that mean? How do you know it is "stuck in bootloader mode" if you are not able to connect? Can you see the advertisements from the bootloader?

 

When i use supply input of 5 volt it works perfectly. But for 12 volts it gives me above error behavior.

 12 volts into the power supply regulator I suppose? What is the input voltage to the nRF at that point?

[ssc]

Hello Edvin,

Device starts broadcasting with "Dfutarg" name when in bootloader mode. Doesn't that mean it it bootloader mode?

12volt into power supply regulator and nRF gets 3.3 V . Input regulator can be given variable voltage from 5 volts to 30 volt.  But as I said earlier it works properly for 5 volt only .. i want to know what are the possibilities that could hamper the function?

[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